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1

RAMAKRISHNAN, BALAJI. "TREATMENT OF MTBE CONTAMINATED WATERS USING AIR STRIPPING AND ADVANCED OXIDATION PROCESSES." University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1131024170.

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2

Stříteský, Luboš. "Využití oxidačních procesů (AOP) pro odstraňování mikropolutantů." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226161.

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This thesis deals with advanced oxidation processes (AOPs) and it’s use for removal of micropollutants from wastewater. The first chapter explains the need AOPs, water quality, pollution and substances that are present in the water. Further, the first chapter outlines approach of the current legislation to micropollutants. The second chapter explains the theory and principle of operation of AOPs. This chapter is divided into two sections. The first section describes AOPs, which were tested at selected WWTP. In the second section, there are described some other AOPs. The third chapter is a literature retrieval of AOPs dealing with the removal of micropollutants. This chapter is focused on the removal of hormones by AOPs using ozone-based AOPs. The fourth chapter describes the actual testing of selected AOPs. The chapter describes selected WWTP, pilot-scale AOP unit and test results. In the last chapter there is designed and described full-scale AOP tertiary unit for removing of micropollutants. The last chapter also contains economic analysis of the proposed tertiary unit.
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3

Graça, Cátia Alexandra Leça. "DEGRADATION OF PERSISTENT PESTICIDES VIA ADVANCED OXIDATION AND REDUCTIVE PROCESSES." Doctoral thesis, Universidade de São Paulo, 2017. http://hdl.handle.net/10362/48570.

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In this Thesis either advanced oxidation or reductive processes are investigated for the degradation of two pesticides considered persistent in the environment: amicarbazone (AMZ) and chlorpyrifos (CP). In chapter I, different advanced oxidation processes (AOPs) driven by sulfate (SO4o-) and hydroxyl radicals (oOH) were applied to the degradation of AMZ. In the first study, several persulfate (PS) activated reactions were explored for AMZ degradation, namely activation with UVA radiation, Fe(II) and H2O2, as well as the combination of UVA radiation with Fe(II), Fe(III) and Fe(III)-complexes. Here, the influence of different reaction variables, such as solution pH, reactants and pesticide initial concentrations, addition of a second oxidant (H2O2) and the addition of different iron catalysts were also investigated. Control experiments regarding the photolysis of iron species in the absence of PS captured our interest and, with the aim of exploring more deeply this process on AMZ degradation, a second investigation was carried out. In this second study, a Doehlert experimental design was applied to investigate the simultaneous effects of two variables on AMZ degradation: pH and Fe(III):carboxylate ratio, where the carboxylate could be oxalate, citrate or tartrate. A response surface model for the observed degradation rate (kobs) as a function of pH and Fe(III):carboxylate ratio was obtained. The processes explored in both aforementioned studies revealed to be effective for AMZ removal, although nothing is known yet about their effectiveness regarding toxicity removal. Given that, a third study was carried out, where the toxicity of AMZ solutions, before and after submission to the processes studied was evaluated towards five microorganisms: Vibrio fischeri (acute toxicity), Tetrahymena thermophile, Chlorella vulgaris (chronic toxicity), Escherichia coli and Bacilus subtilis (antimicrobial activity). The last investigation detailed in chapter I is related with the application of zero-valent-metals on PS activation, which is a subject that links this chapter with the following one. For that, zero-valent-iron (ZVI) was investigated as a PS activator and the influence of variables that help to assess the environmental applicability of this process. In general, organochlorine pesticides reveal a higher resistance to oxidation than reduction, the latter process preferred when the aim is to degrade that important class of contaminants. Therefore, in chapter II the reductive degradation of CP by means of zero-valent-metals and bimetallic particles was investigated. ZVI has been extensively applied for that purpose. However, besides iron, other zero-valent metals can be potential reactive materials for reductive degradation and hence, in this study, the effectiveness of Zn0 and Cu0 was also explored in comparison to that widely reported for ZVI. Furthermore, two different ways of enhancing metals reactivity were here explored: i) by coating ZVI or Zn0 with a more noble metal (Cu), in order to analyze the copper catalytic effect on the bimetallic system; ii) by different surface pretreatments.
Na presente Tese de Doutorado foram abordados tanto processos oxidativos avançados (POA), como processos redutivos por metais de valência zero, na degradação de dois pesticidas considerados persistentes no meio ambiente: amicarbazona (AMZ) e clorpirifós (CP). No capítulo I são apresentados os estudos realizados com diversos POA, mediados por radicais sulfato (SO4o-) e hidroxila (oOH), aplicados da AMZ. Num primeiro estudo foi explorada a ativação do oxidante persulfato (PS), de diferentes formas, tais como radiação UVA, H2O2 e Fe(II), assim como a combinação de radiação UVA com Fe(II), Fe(III) e complexos de Fe(III). Aqui também foram investigados os efeitos de diversas variáveis reacionais, tais como pH, concentração inicial de reagentes e de pesticida, adição de um segundo oxidante (H2O2) e adição de diferentes espécies de ferro. Os testes realizados, para efeito de controle, referentes à irradiação das espécies de Fe(III) na ausência de PS, despertaram o interesse para um estudo mais aprofundado sobre o efeito da fotólise destas espécies na degradação da AMZ, surgindo assim o segundo trabalho. Neste utilizou-se um projeto experimental de Doehlert, para avaliar o efeito de duas variáveis em simultâneo quanto à degradação da AMZ: pH e proporção Fe(III): ligante, sendo o ligante um dos seguintes carboxilatos: oxalato, citrato ou tartarato. Um modelo de superfície de resposta, que correlaciona a taxa de degradação observada (kobs) em função do pH e proporção Fe(III):ligante foi obtido para cada um dos complexos de Fe(III) estudados. Os processos explorados, tanto no primeiro como no segundo estudo, se mostraram eficazes na remoção da AMZ, porém nada se sabe acerca da remoção da toxicidade. Para tal, foi desenvolvido um terceiro estudo dedicado à avaliação da toxicidade da solução de AMZ, antes e após a aplicação de cada um dos processos anteriormente abordados, contra cinco micro-organismos: Vibrio fischeri (toxicidade aguda); Tetrahymena thermophila, Chlorella vulgaris (toxicidade crônica); Escherichia coli e Bacilus subtilis (atividade antimicrobiana). O último estudo abordado no capitulo I é referente à aplicação de metais de valência zero também nos POA, correlacionado assim o capítulo I e o capítulo II. Como tal, foi feito um estudo de ativação de PS por meio de ferro de valência zero (Fe0), em que se investigou a influência de diversas variáveis por forma a inferir sobre a aplicabilidade prática deste processo. Pesticidas organoclorados apresentam maior resistência à degradação por processos oxidativos do que redutivos, sendo preferível o último na degradação desta importante classe de contaminantes. Como tal, o capítulo II se refere à degradação redutiva, por meio de diferentes metais de valência zero e partículas bimetálicas, do pesticida organoclorado CP. Além do amplamente explorado Fe0, outros metais podem ser aplicados neste processo, pelo que, neste estudo, explorou-se a potencialidade de Zn0 e Cu0 comparativamente ao primeiro. Ainda neste estudo foram investigadas duas formas de aumentar a reatividade dos metais: i) no caso do Fe0 e Zn0, revestindo com um metal mais nobre (Cu), por forma a observar o efeito catalisador do último no sistema bimetálico; ii) realizando um pré-tratamento à superfície dos metais.
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4

ROCHA, MANOELA DEMORI LACOMBE PENNA DA. "USE OF ADVANCED OXIDATION PROCESSES FOR PULP MILL WASTEWATER TREATMENT." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2017. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=32797@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
O presente trabalho avalia a utilização de dois diferentes tipos de POA, Fenton-Zero - processo Fenton utilizando ferro zero valente: Fe0/H2O2 - e UV/H2O2 para o tratamento de efluente de indústria de celulose tratado biologicamente. Os parâmetros observados foram DBO, DQO, COT, cor e ABS280nm (medida de compostos ligninícos). Os experimentos foram conduzidos em batelada, em escala de laboratório e utilizando efluente real de indústria de celulose tratado biologicamente. Para os testes com o processo Fenton Zero foram realizados experimentos de acordo com um planejamento fatorial 2 elevado a 3, investigando a influência das variáveis pH, dosagem de peróxido de hidrogênio e massa de ferro zero valente fornecida por volume de solução. Como fonte de ferro foi utilizada lã de aço comercial nas concentrações de 5,5 g/L, 6,5 g/L e 7,5 g/L. As concentrações iniciais de peróxido de hidrogênio estudadas foram de 456,9 mg/L, 913,7 mg/L e 1370,6 mg/L e os valores de pH variaram entre 5.5, 6.5 e 7.5. Foram obtidas médias de remoção de 57,1 por cento de DQO, 67,2 por cento de DBO, 90,5 por cento de Cor, 83,4 por cento de compostos lignínicos e 54 por cento de COT, além de 9,52 mg/L de DBO final e 60,1 mg/L de DQO final. Já os testes com o sistema UV/H2O2 foram conduzidos com o único objetivo de polimento do efluente para reuso pelo processo. Desta maneira, o pH utilizado foi o natural do efluente (7,5) e três doses de H2O2 foram aplicadas, 4,0 g/L, 5,0 g/L e 6,0 g/L estando estas em excesso.
The present work evaluates the use of two different types of AOP: the Zero-Fenton - process using zero valent iron - and UV/H2O2 for the treatment of pulp mill wastewater biologically treated. The observed parameters were BOD, COD, TOC, color and ABS280nm (measure of lignin compounds). The experiments were conducted in batch, lab scale and with real wastewater from biological treatment of a cellulose plant in Brazil. For the Fenton process, experiments were carried out according to a factorial design 23 investigating the influence of the variables pH, hydrogen peroxide dosage and zero-valent iron mass supplied by solution volume. As iron source, commercial steel wool was used in the concentrations of 5.5 g / L, 6.5 g / L and 7.5 g / L. The concentrations of hydrogen peroxide studied were 456.9 mg / L, 913.7 mg / L and 1370.6 mg / L and pH values ranged from 5.5, 6.5 and 7.5. The average removal rate was 57.1 per cent COD, 67.2 per cent COD, 90.5 per cent Color, 83.4 per cent lignin compounds and 54 per cent TOC. Also 9,52 mg/L of final BOD and 60,1 mg/L of final COD. The trials with the UV/H2O2 system, on the other hand, were conducted with the sole objective of polishing the effluent for reuse in the process. The pH used was the effluent s natural (7.5) and three excess doses of H2O2 were applied.
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5

Graça, Cátia Alexandra Leça. "Degradation of persistent pesticides via advanced oxidation and reductive processes." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-03082017-091224/.

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In this Thesis either advanced oxidation or reductive processes are investigated for the degradation of two pesticides considered persistent in the environment: amicarbazone (AMZ) and chlorpyrifos (CP). In chapter I, different advanced oxidation processes (AOPs) driven by sulfate (SO4o-) and hydroxyl radicals (oOH) were applied to the degradation of AMZ. In the first study, several persulfate (PS) activated reactions were explored for AMZ degradation, namely activation with UVA radiation, Fe(II) and H2O2, as well as the combination of UVA radiation with Fe(II), Fe(III) and Fe(III)-complexes. Here, the influence of different reaction variables, such as solution pH, reactants and pesticide initial concentrations, addition of a second oxidant (H2O2) and the addition of different iron catalysts were also investigated. Control experiments regarding the photolysis of iron species in the absence of PS captured our interest and, with the aim of exploring more deeply this process on AMZ degradation, a second investigation was carried out. In this second study, a Doehlert experimental design was applied to investigate the simultaneous effects of two variables on AMZ degradation: pH and Fe(III):carboxylate ratio, where the carboxylate could be oxalate, citrate or tartrate. A response surface model for the observed degradation rate (kobs) as a function of pH and Fe(III):carboxylate ratio was obtained. The processes explored in both aforementioned studies revealed to be effective for AMZ removal, although nothing is known yet about their effectiveness regarding toxicity removal. Given that, a third study was carried out, where the toxicity of AMZ solutions, before and after submission to the processes studied was evaluated towards five microorganisms: Vibrio fischeri (acute toxicity), Tetrahymena thermophile, Chlorella vulgaris (chronic toxicity), Escherichia coli and Bacilus subtilis (antimicrobial activity). The last investigation detailed in chapter I is related with the application of zero-valent-metals on PS activation, which is a subject that links this chapter with the following one. For that, zero-valent-iron (ZVI) was investigated as a PS activator and the influence of variables that help to assess the environmental applicability of this process. In general, organochlorine pesticides reveal a higher resistance to oxidation than reduction, the latter process preferred when the aim is to degrade that important class of contaminants. Therefore, in chapter II the reductive degradation of CP by means of zero-valent-metals and bimetallic particles was investigated. ZVI has been extensively applied for that purpose. However, besides iron, other zero-valent metals can be potential reactive materials for reductive degradation and hence, in this study, the effectiveness of Zn0 and Cu0 was also explored in comparison to that widely reported for ZVI. Furthermore, two different ways of enhancing metals reactivity were here explored: i) by coating ZVI or Zn0 with a more noble metal (Cu), in order to analyze the copper catalytic effect on the bimetallic system; ii) by different surface pretreatments.
Na presente Tese de Doutorado foram abordados tanto processos oxidativos avançados (POA), como processos redutivos por metais de valência zero, na degradação de dois pesticidas considerados persistentes no meio ambiente: amicarbazona (AMZ) e clorpirifós (CP). No capítulo I são apresentados os estudos realizados com diversos POA, mediados por radicais sulfato (SO4o-) e hidroxila (oOH), aplicados da AMZ. Num primeiro estudo foi explorada a ativação do oxidante persulfato (PS), de diferentes formas, tais como radiação UVA, H2O2 e Fe(II), assim como a combinação de radiação UVA com Fe(II), Fe(III) e complexos de Fe(III). Aqui também foram investigados os efeitos de diversas variáveis reacionais, tais como pH, concentração inicial de reagentes e de pesticida, adição de um segundo oxidante (H2O2) e adição de diferentes espécies de ferro. Os testes realizados, para efeito de controle, referentes à irradiação das espécies de Fe(III) na ausência de PS, despertaram o interesse para um estudo mais aprofundado sobre o efeito da fotólise destas espécies na degradação da AMZ, surgindo assim o segundo trabalho. Neste utilizou-se um projeto experimental de Doehlert, para avaliar o efeito de duas variáveis em simultâneo quanto à degradação da AMZ: pH e proporção Fe(III): ligante, sendo o ligante um dos seguintes carboxilatos: oxalato, citrato ou tartarato. Um modelo de superfície de resposta, que correlaciona a taxa de degradação observada (kobs) em função do pH e proporção Fe(III):ligante foi obtido para cada um dos complexos de Fe(III) estudados. Os processos explorados, tanto no primeiro como no segundo estudo, se mostraram eficazes na remoção da AMZ, porém nada se sabe acerca da remoção da toxicidade. Para tal, foi desenvolvido um terceiro estudo dedicado à avaliação da toxicidade da solução de AMZ, antes e após a aplicação de cada um dos processos anteriormente abordados, contra cinco micro-organismos: Vibrio fischeri (toxicidade aguda); Tetrahymena thermophila, Chlorella vulgaris (toxicidade crônica); Escherichia coli e Bacilus subtilis (atividade antimicrobiana). O último estudo abordado no capitulo I é referente à aplicação de metais de valência zero também nos POA, correlacionado assim o capítulo I e o capítulo II. Como tal, foi feito um estudo de ativação de PS por meio de ferro de valência zero (Fe0), em que se investigou a influência de diversas variáveis por forma a inferir sobre a aplicabilidade prática deste processo. Pesticidas organoclorados apresentam maior resistência à degradação por processos oxidativos do que redutivos, sendo preferível o último na degradação desta importante classe de contaminantes. Como tal, o capítulo II se refere à degradação redutiva, por meio de diferentes metais de valência zero e partículas bimetálicas, do pesticida organoclorado CP. Além do amplamente explorado Fe0, outros metais podem ser aplicados neste processo, pelo que, neste estudo, explorou-se a potencialidade de Zn0 e Cu0 comparativamente ao primeiro. Ainda neste estudo foram investigadas duas formas de aumentar a reatividade dos metais: i) no caso do Fe0 e Zn0, revestindo com um metal mais nobre (Cu), por forma a observar o efeito catalisador do último no sistema bimetálico; ii) realizando um pré-tratamento à superfície dos metais.
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6

Cabrera-Codony, Alba. "Siloxane removal in the energy recovery of biogas: sequential adsorption/oxidation processes." Doctoral thesis, Universitat de Girona, 2016. http://hdl.handle.net/10803/399731.

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The thesis deals with removal of organosilicon compounds in the energy recovery of biogas. Alternative adsorbents for the siloxane removal were studied, and the physical and chemical mechanisms involved in the siloxane adsorption were discovered, which improved the yield of the adsorption and regeneration technologies using both activated carbons and zeolites. Moreover, several technologies based on advanced oxidation processes have been applied in order to regenerate and reuse the exhausted adsorbents. The thesis studies the siloxane removal at lab-scale close to real scenario conditions, including the competitive adsorption with compounds usually found in biogas, in the presence of humidity and with the same gas matrix, which allowed to select the most efficient materials for this purpose. Therefore, the knowledge reported in the thesis dissertation is directly transferable to field application to upgrade the siloxane removal system
Aquesta tesi estudia l'eliminació de compostos volàtis de silici (siloxans) per la recuperació energètica del biogàs. Es van estudiar diferents adsorbents per l'adsorció de siloxans, determinants les propietats físico-químiques superficials que en condicionen l'eficiència, permetent millorar el rendiment de l'adsorció i permetent la regeneració en carbons actius i zeolites esgotats. La tesi estudia l'eliminació de siloxans a escala de laboratori en condicions properes a les reals del biogàs, incloent l'adosrció competitiva amb altres compostos orgànics volàtics, en presència d'humitat i amb diferents matrius gasoses, la qual cosa va permetre seleccionar els materials òptims per aquest propòsit.Per tant el coneixement derivat d'aquesta tesi és directament transferible per tal de millorar els sistemes d'eliminació siloxanes
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7

Rani, Rupam. "REMOVAL OF EMERGING CONTAMINANTS FROM AQUEOUS SOLUTION BY OZONE -BASED PROCESSES." Master's thesis, Temple University Libraries, 2013. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/214782.

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Civil Engineering
M.S.Env.E.
The presence of emerging contaminants (ECs) in water and wastewater systems has become a subject of significant concern worldwide. These emerging contaminants are complex organic molecules which potentially affect human health and environment. Conventional wastewater treatment plants are unable to completely remove these contaminants from water and therefore can discharge them into environment. The need to develop effective methods for ECs removal is essential. This study assess the potential of ozone based advanced oxidation processes (AOP) to oxidize number of emerging contaminants. Different combinations of ozone with hydrogen peroxide and sodium persulfate were tested. For this study 1-4, dioxane, perfluorinated compounds (PFCs), N,N-Diethyl-metatoluamide, and three pharmaceuticals sulfamethoxazole, trimethoprim and carbamazepine have been selected. The effect of different process parameters such as chemical dosages, ozone weight percent, ozone flow rates, etc. on destruction of ECs were examined. It was observed that 1, 4-dioxane were persistent to direct ozone reaction, however were easily oxidized by hydroxyl radical. However, ozonation was solely very effective (> 99 %) in removing pharmaceuticals such as sulfamethoxaole, trimethoprim and carbamazepine. It was not very efficient for the removal of perfluorinated compound and N,N-Diethylmeta-toluamide. The operational conditions were optimized for maximum removal of every compound and their influence on the degradation process is discussed.
Temple University--Theses
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8

Hansson, Henrik. "TREATMENT OF WASTEWATER GENERATED BY WOOD-BASED DRY INDUSTRIES: ADVANCED OXIDATION PROCESSES & ELECTROCOAGULATION." Doctoral thesis, Linnéuniversitetet, Institutionen för biologi och miljö (BOM), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-36437.

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Wood is a material with an enormous number of applications. For decades, the development of wastewater treatment technologies tailored for the wood sector has focused on those industries that have water as an integral part of the industrial production, such as paper and pulp. However, there is a large and potentially growing sector that has been neglected, which is formed by industries in which water is not part of their production line, as for example, the wood floor and furniture industries (named wood-based dry industries). These industries still produces relatively low volumes of highly polluted wastewaters, with COD up to 30,000 mg/L, due to cleaning/washing procedure (named cleaning wastewaters). These cleaning wastewaters are often sent to the municipal wastewater treatment plant after dilution with potable water. Once there, recalcitrant pollutants are diluted and discharged into recipient water bodies or trapped in the municipal wastewater sludge. Another type of contaminated water these “dry industries” often generate in high volumes, and which is usually discharged with no previous treatment, is storm-water containing contaminants that have leached from large wood storage areas. The overall aim of this thesis was to increase the level of knowledge and competence and to present on-site wastewater treatment options for wood-based dry industries using the wood floor industry as a case-study, with a focus on combined treatment methods and solutions applicable to both the cleaning wastewater and storm-water. Among the treatment technologies investigated, electrocoagulation was studied both as a standalone treatment and combined with sorption using activated carbon. The combined treatment achieved a COD reduction of approximately 70%. Some advanced oxidation processes (AOP) were also studied: a COD reduction of approximately 70% was achieved by photo-Fenton, but the most successful AOP was ozone combined with UV light, were a COD reduction around 90% was achieved, with additional improvement in the biodegradability of the treated effluent. Ozone also proved to be effective in degrading organic compounds (approximately 70% COD reduction) and enhanced the biodegradability of the storm-water runoff from wood storage areas. The results have shown that the application of ozone can be considered an option for treatment of cleaning wastewaters and possibly for storm-water biodegradation enhancement.
Trä är ett material med ett stort antal möjliga användningsområden. Inom träindustrin har utvecklingen av vattenbehandlingsmetoder varit inriktat på de branscher som har vatten som en del av produktionen, såsom papper- och massaindustrin. Men det finns en stor och potentiellt växande sektor inom träindustrin som har försummats, den utgörs av industrier som inte har vatten som en del av produktionen, t.ex. trägolv och trämöbel industrier. Trots detta så producerar dessa industrier fortfarande relativt kraftigt förorenade avloppsvatten med t.ex. COD-värden upp till 30000 mg/l men i relativt låga volymer. Dessa avloppsvatten uppkommer vid rengöring av maskiner och städning av lokaler, varefter de oftast efter utspädning med dricksvatten skickas till det kommunala reningsverket. Väl där späds det förorenade vattnet vidare ut med annat inkommande vatten men passerar dock till stor del obehandlat och släpps ut i mottagande vattendrag eller så fastnar föroreningarna i avloppsslamet. Dagvatten är en annan typ av förorenat vatten från dessa "torra industrier" som ofta genereras i stora volymer och innehåller föroreningar som lakats från de trämaterial som förvaras i de stora upplag som ofta förekommer vid denna typ av industrier. Det övergripande syftet med avhandlingen var att öka kunskapen och kompetensen för att kunna miljömässigt riktigt och ekonomiskt billigt behandla industriavloppsvatten lokalt på plats inom trävaruindustrin, genom att använda en trä-golvsindustri som fallstudie. Fokus lades på kombinerade behandlingsmetoder och lösningar som skulle kunna vara lämpliga både för industriavloppsvatten och dagvatten. Ett antal behandlingstekniker har undersökts; elektrokoagulering studerades både som en fristående behandling och i kombination med aktivt kol. Den kombinerade behandlingen gav en COD-reduktion på ungefär 70 %. Flera avancerade oxidationsprocesser (AOP) studerades också, och en COD-reduktion på cirka 70% uppnåddes med en kombination av UV-ljus och Fenton behandling. Den mest framgångsrika behandlingen var ozon i kombination med UV-ljus där en COD-reduktion runt 90 % uppnåddes varvid en avsevärd förbättring av den biologisk nedbrytbarhet på det behandlade avloppsvattenet erhölls. Ozon visade sig också vara effektivt för nedbrytning av organiska föreningar (ca 70% COD reduktion) och förbättrade den biologiska nedbrytbarheten av föroreningarna i dagvattnet från den studerade industrin. Resultaten har visat att ozon kan anses vara ett lämpligt alternativ för att behandla industriavloppsvatten inom trävarusektorn och möjligen för att öka den biologiska nedbrytbarheten av dagvattnet från dessa industrier
Integrated Approach for Handling of Industrial Wastewater and Stormwater
Triple Helix Collaboration on Industrial Water Conservation in Småland and the Islands
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9

Han, Hyungjin Civil &amp Environmental Engineering Faculty of Engineering UNSW. "Mechanisms and modelling of sonochemically-mediated free radical degradation of contaminants." Awarded by:University of New South Wales. Civil & Environmental Engineering, 2009. http://handle.unsw.edu.au/1959.4/43485.

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Hazardous and recalcitrant pollutants in the environments have led to a great many environmental issues these days. Many researchers have focused on the approaches to treatment of these pollutants which contaminate environments such as soil, surface and groundwater. As an advanced oxidation processes (AOPs), sonolysis which is the oxidation technology involving the use of ultrasonic irradiation, has proven to be successful for the treatment and remediation of contaminated environments. In this thesis, hydrogen peroxide formation and formic acid degradation by ultrasonic irradiation of well-characterised solutions are described under various conditions in order to determinate reaction mechanism by which peroxide degradation and contaminant degradation occur. The effect of gas properties and frequency on hydrogen peroxide and formic acid degradation are examined. Experimental results obtained are analyzed in light of the reactions occurring. Successful mathematical modeling of the result s obtained confirms that, for the most part, hydrogen peroxide and formic degradation occur by free radical generation within bubbles with subsequent transfer of these radicals to the bubble-water interface where the majority of the degradation occurs. The effect of Fe(II) addition which can lead to Fenton reactions in the bulk solution are also investigated. Experimental and model results show that the heterogeneous reactions can enhance the degradation of formic acid in the presence of Fe(II). Oxidation of phenol by ultrasonic irradiation under a variety of initial conditions and solution environments is also described and validated by a simple kinetic model. The model developed will be useful for improving our understanding of free radicals behaviour and the interplay between free radical generation and contaminant degradation.
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10

Demir, Duz Hande. "Application of Advanced Oxidation Processes in the Reclamation of Wastewaters from the Oil & Gas Sector." Doctoral thesis, Universitat Rovira i Virgili, 2020. http://hdl.handle.net/10803/670759.

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Aquesta tesi s'emmarca dins de dos projectes relacionats amb la recuperació (tractament + reutilització) d'aigües residuals generades per la indústria de petroli i gas. L'objectiu del primer projecte va ser la reutilització d'aigua residual generada per aquest sector mitjançant el tractament dels anomenats efluents "downstream" amb processos d'oxidació avançats (AOPs). Amb aquest objectu, es van estudiar diversos processos AOPs fotocatalítics i basats en ozó, els quals es van aplicar, en primer lloc, per al tractament d'una aigua sintètica amb una composició complexa representativa d'aigua residual de refineria (SRW). Després dels resultats obtinguts amb SRW, es va investigar el rendiment del tractament en tres aigües residuals reals diferents amb l'objectiu d'assolir els requisits per a la reutilització d'aigua a la planta. El segon projecte es va enfocar en el tractament d'aigua residual procedent del procés de sorres petrolíferes (OSPW), que actualment es troba emmagatzemada en estanys causa de la política de descàrrega zero a la regió d'Alberta, Canadà. En primer lloc, es van comparar els tractaments d'ozonització i UV amb diferents oxidants i pH. El tractament amb UV/Fenton va resultar ser un mètode eficaç per eliminar els components orgànics presents en l'efluent que causen toxicitat aguda. També es van investigar les activitats catalítiques de catalitzadors de carbó activat granulat prèviament dopats amb N o N/S i Fe(III). Es va realitzar una selecció dels catalitzadors més prometedors mitjançant disseny factorial fraccional en l'ozonització catalítica d'una aigua sintètica. Posteriorment, els materials seleccionats es van investigar més a fons per al tractament de OSPW real. Es van estudiar, a més, processos AOP basats en ozó en combinació amb H2O2 i UVC amb l'objectiu d'assolir la mineralització dels contaminants orgànics, inclosos els àcids naftènics presents en l'efluent. Un augment en la mineralització repercuteix positivament en la reducció de la toxicitat. Per primera vegada es presenta l'estudi de la combinació de UVC amb tractaments basats en O3 per tractar la OSPW.
Esta tesis se enmarca dentro de dos proyectos relacionados con la recuperación (tratamiento + reutilización) de aguas residuales generadas por la industria del petróleo y gas. El objetivo del primer proyecto fue la reutilización de agua residual generada por la industria del petróleo y gas mediante el tratamiento de los denominados efluentes "downstream" con procesos de oxidación avanzados (AOPs). Para ello, se estudiaron varios procesos AOPs fotocatalíticos y basados en ozono, los cuales se aplicaron, en primer lugar, para el tratamiento de un agua sintética con una composición compleja representativa de agua residual de refinería (SRW). Tras los resultados obtenidos con SRW, se investigó el rendimiento del tratamiento en tres aguas residuales reales diferentes con el objetivo de alcanzar los requisitos para la reutilización del agua en la planta. El segundo proyecto se enfocó en el tratamiento de agua residual procedente del proceso de arenas petrolíferas (OSPW), que actualmente se encuentra almacenada en estanques debido a la política de descarga cero en la región de Alberta, en Canadá. En primer lugar, se compararon los tratamientos de ozonización y UV con diferentes oxidantes y pH. El tratamiento con UV/Fenton resultó ser un método eficaz para eliminar los componentes orgánicos presentes en el efluente que causan toxicidad aguda. También se investigaron las actividades catalíticas de catalizadores de carbón activado granulado previamente dopados con N o N/S y Fe (III). Se realizó una selección de los catalizadores más prometedores mediante diseño factorial fraccional en la ozonización catalítica de un agua sintética. Posteriormente, los materiales seleccionados se investigaron más a fondo para el tratamiento de OSPW real. Se estudiaron, además, procesos AOP basados en ozono en combinación con H2O2 y UVC con el objetivo de alcanzar la mineralización de los contaminantes orgánicos, incluidos los ácidos nafténicos presentes en el efluente. Un aumento en la mineralización repercute positivamente en la reducción de la toxicidad. Por primera vez se presenta el estudio de la combinación de UVC con tratamientos basados en O3 para tratar la OSPW.
This thesis has been developed within two projects dealing with the reclamation of wastewater generated by the oil & gas industry. The first project aimed at water reuse in the oil & gas sector treating the downstream effluents by advanced oxidation processes (AOPs). For this, several photo-based and ozone-based AOPs were assessed in detail starting from a synthetic refinery wastewater (SRW) with a complex composition. After the initial screening on SRW, the treatment performance of the different AOPs was investigated with three different real wastewaters, aiming at reaching the requirements for water reuse in the plant. The second project considered the treatment of oil sands process water (OSPW) currently stored in tailing ponds because of the zero-discharge policy in Alberta region, in Canada. Firstly, catalytic ozone-based and UV-based treatments with different oxidants and operating pH were compared. UV/Fenton treatment was considered as an effective method for removing the organic components present in the effluent that cause acute toxicity. The catalytic activities of granular activated carbon-based materials previously doped with heteroatom (N or N/S) and Fe (III) were also investigated. For catalytic ozonation of a synthetic water, a catalyst selection was performed based on the fractional factorial design. Afterwards, the selected materials were investigated further for the treatment of real OSPW. The use of ozone-based AOPs including H2O2 and UVC to achieve mineralization was examined in detail, while also aiming at reduction in toxicity arising from the organic components including naphthenic acids present in the effluent. UVC combination to O3-based treatments was studied for the first time to treat OSPW.
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11

Badmus, Kassim Olasunkanmi. "Treatment of persistent organic pollutants in wastewater with combined advanced oxidation." University of the Western Cape, 2019. http://hdl.handle.net/11394/6785.

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Philosophiae Doctor - PhD
Persistent organic pollutants (POPs) are very tenacious wastewater contaminants with negative impact on the ecosystem. The two major sources of POPs are wastewater from textile industries and pharmaceutical industries. They are known for their recalcitrance and circumvention of nearly all the known wastewater treatment procedures. However, the wastewater treatment methods which applied advanced oxidation processes (AOPs) are documented for their successful remediation of POPs. AOPs are a group of water treatment technologies which is centered on the generation of OH radicals for the purpose of oxidizing recalcitrant organic contaminants content of wastewater to their inert end products. Circumvention of the reported demerits of AOPs such as low degradation efficiency, generation of toxic intermediates, massive sludge production, high energy expenditure and operational cost can be done through the application of the combined AOPs in the wastewater treatment procedure. The resultant mineralisation of the POPs content of wastewater is due to the synergistic effect of the OH radicals produced in the combined AOPs. Hydrodynamic cavitation is the application of the pressure variation in a liquid flowing through the venturi or orifice plates. This results in generation, growth, implosion and subsequent production of OH radicals in the liquid matrix. The generated OH radical in the jet loop hydrodynamic cavitation was applied as a form of advanced oxidation process in combination with hydrogen peroxide, iron (II) oxides or the synthesized green nano zero valent iron (gnZVI) for the treatment of simulated textile and pharmaceutical wastewater.
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12

Sable, Shailesh Subhashrao. "Development of novel catalytic materials for removal of emerging organic pollutants by advanced oxidation processes (AOPS)." Doctoral thesis, Universitat Rovira i Virgili, 2014. http://hdl.handle.net/10803/284945.

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L'objectiu principal del nostre treball és el desenvolupament de nous materials catalítics i mètodes prometedors, eficients i respectuosos amb el medi ambient, per la degradació i la mineralització de contaminants orgànics mitjançant Processos d'Oxidació Avançada (POA) per al tractament d'aigües residuals. Amb aquest propòsit, diverses famílies de catalitzadors han estat sintetitzades per diferents mètodes i s'ha evaluat la seva activitat catalítica en els processos d'oxidació avançada d'ozonització catalítica i el procés Fenton heterogeni, tant per al tractament de compostos farmacèutics emergents com l'àcid clofíbric (CFA) com compostos recalcitrants d'origen industrial com fenol, en condicions ambientals. Entre tots els catalitzadors estudiats en el procés d'ozonització catalítica, el catalitzador d'òxid de Cu-Al preparat per un mètode de co-precipitació, ha mostrat una excel·lent activitat i estabilitat en l'ozonització catalítica de CFA, assolint un 82% i 96% de mineralització en 2 i 6 h, respectivament. En quant al procés Fenton, catalitzadors d'òxid de Fe presentant fases d'hematita i maghemita, i a les que s'han afegit petites quantitats de Pd (Pd/FeOOH) han mostrat molt bons resultats en l'eliminació de CFA mitjançant un procés Fenton heterogeni. En el procés combinat d'adsorció+oxidació, la zeolita ZSM5 contenint Fe i Pd (Pd/Fe-ZSM5) ha presentat una bona activitat en l'eliminació de fenol mitjançant adsorció i oxidació per un procés Fenton heterogeni.
El objetivo principal de nuestro trabajo es el desarrollo de nuevos materiales catalíticos y métodos prometedores, eficientes y respetuosos con el medio ambiente para la degradación y la mineralización de contaminantes orgánicos por medio de Procesos de Oxidación Avanzada (POA) para el tratamiento de aguas residuales. Con este propósito, varias familias de catalizadores han sido sintetizados por diferentes métodos y se ha evaluado su actividad catalítica en los procesos de oxidación avanzada de ozonización catalítica y el proceso Fenton heterogéneo, tanto para la eliminación de compuestos farmacéuticos emergentes como el ácido clofíbrico (CFA), como compuestos recalcitrantes de origen industrial, como fenol, en condiciones ambientales. Entre todos los catalizadores estudiados en el proceso de ozonización catalítica, el catalizador de óxido de Cu-Al preparado por un método de co-precipitación, ha mostrado una excelente actividad y estabilidad en la ozonización catalítica de CFA, alcanzando un 82% y 96% de mineralización en 2 y 6 h, respectivamente. En cuanto al proceso Fenton, catalizadores de óxido de Fe conteniendo fases de hematita y maghemita y a los que se le ha añadido pequeñas cantidades de Pd (Pd/FeOOH) han mostrado muy buenos resultados en la eliminación de CFA mediante un proceso Fenton heterogéneo. En el proceso combinado de adsorción+oxidación, la zeolita ZSM5 conteniendo Fe y Pd (Pd/Fe-ZSM5) ha presentado un buen desempeño en la eliminación de fenol mediante adsorción y oxidación por un proceso Fenton heterogéneo.
The main aim of our work is to develop new catalytic materials and promising, efficient and environmental-friendly methods for the degradation and mineralization of organic pollutants by means of Advanced Oxidation Processes (AOPs) for wastewater treatment. For this purpose various families of catalysts were synthesized by different methods and their potential catalytic activity have been evaluated in Advanced Oxidation Processes (AOPs) such as ozonation and Fenton-like process for treating emerging pharmaceutical compounds like clofibric acid (CFA) and recalcitrant compounds like phenol at ambient conditions. Among all the catalysts screened, the Cu-Al oxide catalyst prepared by a co-precipitation method, showed an excellent activity and stability in catalytic ozonation of CFA, achieving 82% and 96% mineralization in 2 and 6h, respectively. As for the Fenton process, catalysts containing Fe oxides presenting hematite and maghemite phases, and to which small amounts of Pd were added (Pd/FeOOH) have shown very good results in the removal of CFA by means of heterogeneous Fenton process. In the combined process of adsorption+oxidation, ZSM5 zeolite containing Fe and Pd (Pd/Fe-ZSM5) has presented good performance in the removal of phenol by adsorption and oxidation by heterogeneous Fenton-like process.
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13

Andrade, Juliano de Almeida. "Otimização da reação de fenton visando aplicações na remediação in-situ e ex-situ de aguas subterraneas." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249632.

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Orientador: Wilson de Figueiredo Jardim
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
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Mestrado
Quimica Analitica
Mestre em Química
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14

Wong, Kit Iong. "Chemical removal of dichloromethane (DCM) from contaminated water using advanced oxidation processes (AOPs) :Hydrogen Peroxide Ozone UV." Thesis, University of Macau, 2018. http://umaclib3.umac.mo/record=b3868740.

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15

Acar, Ebru. "Oxidation Of Acid Red 151 Solutions By Peroxone (o3/h2o2) Process." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605527/index.pdf.

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Wastewaters from textile industry contain organic dyes, which cannot be easily treated by biological methods. Therefore, pretreatment by an advanced oxidation process (AOP) is needed in order to produce more readily biodegradable compounds and to remove color and chemical oxygen demand (COD) simultaneously. In this research, ozone (O3) is combined with hydrogen peroxide (H2O2) for the advanced oxidation of an azo dye solution, namely aqueous solution of Acid Red 151, which is called as &ldquo
Peroxone process&rdquo
. The aim of the study is to enhance the ozonation efficiency in treating the waste dye solution. The effects of pH, initial dye and initial ozone concentrations and the concentration ratio of initial H2O2 to initial O3 on color and COD removals were investigated. Also, the kinetics of O3-dye reaction in the presence of H2O2 was approximately determined. As a result of the experimental study, it was seen that an increase in the initial dye concentration at a constant pH and initial ozone concentration did not change the COD % removal significantly, from a statistical analysis of the data. The results obtained at pH values of 2.5 and 7 gave higher oxidation efficiencies in terms of color and COD removals compared to those at pH of 10. The best initial molar ratio of H2O2 to O3 was found to be 0.5, which yielded highest treatment efficiency for each pH value studied. The results of the excess dye experiments suggest that the ozonation of Acid Red 151 follows an average first order reaction with respect to ozone at pH=2.5 and pH=7 whereas it is around 0.56 at pH=10. By Initial Rate Method, the orders with respect to individual reactants of O3 and dye were determined as one, the total order of the reaction being two for all the studied pH. As a conclusion, a further study of the peroxone process at a pH of 10 can be recommended to determine the reaction kinetics and mechanism at this pH, where radicals play an important role.
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16

Filho, Saulo Afonso de Almeida. "Processos oxidativos com hidroperóxidos, persulfatos ou perácidos, catalisados por espécies de cobre e de ferro com potencial aplicação em química ambiental." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-29072015-111500/.

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Neste trabalho, foram sintetizados complexos de cobre e ferro, com ligantes imínicos, obtidos a partir de 2-acetilpiridina e 2-(2-aminoetilpiridina) (apyepy), ou 2-acetilpiridina e 2-(aminometil)benzimidazol (apyambi), e com ligantes comerciais (ácido nitrilotriacético ou picolínico), capazes de catalisar a oxidação de poluentes, como benzeno, tolueno, etilbenzeno e xilenos (BTEX). Foi utilizado o tolueno como composto-modelo destes poluentes, que foi degradado com o uso de peróxido de hidrogênio, persulfato de sódio, ácido peracético ou peróxidos de metais alcalinos como agentes oxidantes. Os ligantes imínicos foram obtidos a partir de precursores carbonílicos e amínicos adequados, através de reações de condensação, e os correspondentes complexos metálicos de cobre(II), ferro(II) ou ferro(III) foram isolados utilizando métodos usuais de nosso laboratório. A caracterização dos compostos foi feita através de diversas técnicas analíticas e espectroscópicas: UV/Vis, infravermelho (IV) e de ressonância paramagnética eletrônica (EPR). Posteriormente, foi feita a inserção desses complexos de ferro e de cobre sintetizados em matrizes inorgânicas de niobatos e a verificação de sua reatividade em comparação com as mesmas espécies em solução. Monitorou-se a degradação do tolueno pelo peróxido de hidrogênio por cromatografia gasosa e os resultados obtidos indicaram boa atividade catalítica dos complexos, tanto em solução como inseridos em matrizes de niobato. Em solução, os complexos imínicos foram mais ativos que os de ligantes comerciais. Os compostos de ferro com ambos os ligantes imínicos mostraram-se melhores catalisadores que os correspondentes de cobre e um dos ligantes testados foi o mais eficiente (apyepy) com ambos os metais. A inserção em niobatos, aparentemente, preserva o catalisador e mantém sua atividade por mais tempo, mostrando que a inserção em niobatos beneficia o processo
In this work, iron and copper complexes were synthesized, with imine ligands obtained from 2-acetylpyridine and 2-(2-aminethylpiridine) (apyepy), or 2- acetylpyridine and 2- (aminomethyl)benzimidazole (apyambi) and commercial ligands (nitriletriacetic and picolinic acids) that are able to catalyze the oxidation of pollutant compounds as benzene, , ethylbenzene and xilenes (BTEX). Toluene was used as model compound of those pollutants, and its degradation was verified by using hydrogen peroxide, alkaline peroxide, sodium persulfate, or peracetic acid as oxidant agent. The imine ligands were obtained from adequate carbonyl and amine precursors, in condensation reactions, and the corresponding copper(II), iron(II) and iron(III) complexes were isolated by usual methods developed in our laboratory. Their characterization was carried out by analytical and spectroscopic techniques (UV/Vis, IR and EPR). Those complexes were then inserted in inorganic matrices (niobates) e its reactivity were compared to that of the analogous species in solution. Toluene degradation by hydrogen peroxide was monitored by gas chromatography, and the results showed good catalytic activity of all the complexes, both in solution and inserted into niobate matrices. In solution, the imine complexes were more efficient than the species with commercial ligands. The iron compounds with both imine ligands acted as better catalysts than the corresponding copper species, and for both metals those with the ligand apyepy were the most efficient in both cases. The insertion in niobates apparently preserves the catalyst and maintains its activity for longer, attesting that the insertion ameliorated the process.
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17

Silva, Marcos Erick Rodrigues da. "Tratamento AnaerÃbio de Efluentes Contendo Corantes e Estudos de PÃs-Tratamento e Ecotoxicidade." Universidade Federal do CearÃ, 2011. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=5790.

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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
O descarte de efluentes tÃxteis em Ãguas superficiais representa um sÃrio problema ambiental e de saÃde pÃblica devido, principalmente, à presenÃa de corantes na sua composiÃÃo, muitos dos quais sÃo potencialmente tÃxicos e carcinogÃnicos. A remoÃÃo de cor e a mineralizaÃÃo de seus subprodutos à uma das maiores dificuldades enfrentadas pelas estaÃÃes de tratamento de efluentes das indÃstrias desse segmento. Nesta pesquisa, buscou-se avaliar o tratamento de efluentes tÃxteis em sistemas anaerÃbios de um e dois estÃgios, estudar opÃÃes de pÃs-tratamento por processos biolÃgicos aerÃbios e de oxidaÃÃo avanÃada, e utilizar testes de ecotoxicidade no estudo dos diversos efluentes produzidos. Foram realizados experimentos com sistemas anaerÃbios de um (R1) e dois estÃgios (R2) tratando esgotos tÃxteis real e sintÃticos. Nestes experimentos, foram avaliados o efeito da concentraÃÃo do corante, concentraÃÃo do doador de elÃtrons externo, o tempo de detenÃÃo hidrÃulica (TDH) e o efeito do mediador redox antraquinona-2,6-dissulfonato (AQDS) na eficiÃncia de descoloraÃÃo. Outros dois sistemas anaerÃbios de um estÃgio (R3 e R4) foram operados em paralelo, alimentados com esgoto tÃxtil real com TDH de 12h a fim de avaliar o efeito do AQDS na descoloraÃÃo de efluentes reais. Durante o pÃs-tratamento aerÃbio, foi avaliada a aplicaÃÃo de um reator de lodos ativados em batelada seqÃencial com ciclo total de 24h, operando com os efluentes, sintÃtico e real, previamente tratados no reator UASB. Avaliou-se, tambÃm, a aplicaÃÃo do processo de oxidaÃÃo avanÃada (POA) do tipo UV/H2O2 como opÃÃo de pÃs-tratamento dos efluentes tÃxteis tratados no reator UASB, tanto em relaÃÃo à descoloraÃÃo quanto na mineralizaÃÃo dos subprodutos gerados na reduÃÃo dos corantes. A avaliaÃÃo da toxicidade dos efluentes foi realizada pelos ensaios de toxicidade aguda utilizando a Daphnia magna como organismo teste. Os resultados dessa pesquisa revelaram que o sistema anaerÃbio de dois estÃgios mostrou-se mais estÃvel que o sistema de um estÃgio quando operado como o esgoto real e sintÃtico com os corantes Congo Red (CR) e Reactive Black 5 (RB5) e mais eficiente para o corante RR2 na ausÃncia de AQDS. Entretanto, na presenÃa do AQDS a eficiÃncia de descoloraÃÃo do Reactive Red 2 (RR2) foi elevada para os dois sistemas, mascarando o efeito da separaÃÃo de fase. Para o efluente tÃxtil real, nÃo foi verificado efeito algum da aplicaÃÃo do AQDS no R3, mesmo em baixo TDH e limitada concentraÃÃo de doador de elÃtrons. O pÃs-tratamento dos efluentes real e sintÃticos no reator aerÃbio foi capaz de reduzir a DQO abaixo de valor exigido pela portaria 154/02 da SEMACE. O processo de oxidaÃÃo avanÃada com UV/ H2O2 mostrou-se eficaz na remoÃÃo de cor e DQO dos efluentes tÃxtil real e sintÃticos. Os testes de toxicidade aguda ratificaram o potencial tÃxico dos efluentes tÃxteis e os subprodutos de sua degradaÃÃo assim como a capacidade de mineralizaÃÃo das aminas em sistemas seqÃenciais anaerÃbio/aerÃbio.
Disposal of textile effluents in surface waters represents a serious environmental and public health problem mainly due to the presence of dyes in their composition, many of which are potentially toxic and carcinogenic. The color removal and mineralization of byproducts is the major difficulty faced by the wastewater treatment plants of these industries. This thesis studied the treatment of textile effluents in one-stage and two-stage anaerobic systems, post-treatment options by using aerobic biological and advanced oxidation processes, and use the ecotoxicity tests for the various effluents produced. Experiments were performed in one-stage (R1) and two-stage (R2) anaerobic systems treating real and synthetic textile wastewaters. In these experiments, we evaluated the dye concentration effect, as well as external electron donor concentration, hydraulic retention time (HRT) and the redox mediator anthraquinone-2,6-disulfonate (AQDS) effect on color removal efficiency. Two other one-stage anaerobic systems (R3 and R4) were operated in parallel at the HRT of 12 hours and fed with real textile wastewater to assess the AQDS effect on the decolourisation of real textile effluents. During the aerobic post-treatment, we evaluated the application of sequencing batch reactor (SBR) with 24 hours total cycle to treat synthetic and real textile wastewaters pre-treated in the UASB reactor. We also evaluated the application of UV/H2O2 advanced oxidation process (AOP) to treat real textile wastewaters pre-treated in the UASB reactor, both in terms of color removal and mineralization of byproducts generated upon dye reduction. The evaluation of the effluents toxicity was performed by acute toxicity tests using Daphnia magna as test organism. The results revealed that the two-stage anaerobic system was more stable than the one-stage system for both real and the synthetic dyes Congo Red (CR) and Reactive Black 5 (RB5), and more efficient for the dye RR2 in absence of AQDS. However, in the presence of AQDS, color removal efficiency of RR2 was higher for both systems, masking the effect of phase separation. For real textile wastewater, it was not observed any effect of the AQDS application on R3, even when a short HRT or low electron donor concentration was applied. The aerobic and AOP post-treatments were able to reduce the effluents COD to values lower than the limits defined at the Legislation n 154 of SEMACE. The UV/H2O2 AOP-type was effective in removing color and COD from both real and synthetic textile effluents. The acute toxicity tests revealed the toxic potential of textile effluents and their by-products as well as the aromatic amines mineralization in anaerobic/aerobic systems.
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18

Santos, Rodrigo Morais Menezes dos [UNESP]. "Materiais derivados de hidróxidos duplos lamelares: síntese, caracterização e aplicação em adsorção e processos avançados de oxidação." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/132959.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A contaminação de recursos hídricos por diversos poluentes orgânicos, como os corantes têxteis, tem causado sérios problemas ambientais. Alguns processos de descontaminação utilizam materiais sólidos para adsorção/sorção, com características apropriadas para a implantação em escala industrial, apresentando alta eficiência e baixo custo. Os Processos Avançados de Oxidação (AOP), como a fotocatálise heterogênea, também têm sido empregados na descontaminação de águas, convertendo os poluentes orgânicos em substâncias mais facilmente degradáveis, inertes ou inofensivas. Materiais multifuncionais como os Hidróxidos Duplos Lamelares (HDL) e seus derivados se mostram promissores tanto em processos adsortivos como fotocatalíticos. No presente trabalho foi dado enfoque ao processo de adsorção de um azocorante têxtil, utilizando HDL do sistema ZnAl-CO3 e o óxido misto obtido no tratamento térmico a 450°C. Os materiais apresentaram características interessantes e alta capacidade de remoção do corante. As isotermas de adsorção apresentaram boa correlação com o modelo de Langmuir e o cálculo de seus parâmetros revelou que a capacidade máxima adsortiva do material calcinado foi cerca de 6 vezes superior ao material não calcinado, 1587,1 mg⋅g-1 e 261,8 mg⋅g-1, respectivamente. A maior capacidade de adsorção/sorção foi atribuída ao melhoramento das propriedades texturais e ao comportamento da “regeneração” da estrutura HDL pelo precursor calcinado. Os resultados revelaram que o controle cinético do processo é uma etapa de adsorção química, e os parâmetros termodinâmicos calculados mostraram que o processo de adsorção é espontâneo e endotérmico. Os experimentos de conversão fotocatalítica de corante mostraram que os derivados da calcinação dos HDL são materiais promissores para serem utilizados nos AOP. A formação do nanocompósito ZnAl2O4/ZnO no material calcinado a 850°C, mostrou os melhores resultados de conversão, pela estratégia de acoplamento de bandas para separação de cargas, que diminui os problemas relacionados com a recombinação dos portadores de carga, além da maior absorbância no UV. Dessa forma, os resultados obtidos mostram a multifuncionalidade desses materiais, e fornecem novas evidências sobre a reconstrução de HDL pelo “efeito memória”, tópico de intensa discussão na literatura.
The contamination of water resources by several organic pollutants, including textile dyes, which have caused serious environmental problems. Solid materials for adsorption with appropriate features to be employed in industrial scale, such as high efficiency and low cost have been used in some decontamination processes. The Advanced Oxidation Processes (AOP) including heterogeneous photocatalysis, have also been used in water treatment, converting the organic pollutants into easily degradable, inert or harmless substances. Multifunctional materials, such as the Layered Double Hydroxides (LDH) and their derivatives, show potential in both adsorptive and photocatalytic processes. In this work the textile azo dye adsorption process using a ZnAl-CO3 LDH and the mixed oxide obtained from thermal treatment at 450 °C were focused. The materials presented interesting features and high removal capacity for the dye. The adsorption isotherms showed good correlation with the Langmuir isotherm model and the calculated parameters revealed that the maximum adsorption capacity of the calcined material was about 6 times higher than the non-calcined material, 1587.1 mg⋅g-1 and 261.8 mg⋅g-1, respectively. The higher adsorption capacity was assigned to the improvement of the textural properties and to the LDH-structure recovery from the calcined precursor. The results showed kinetic control of the process is a chemical adsorption step, and the calculated thermodynamic parameters showed the adsorption process is spontaneous and endothermic. The dye photocatalytic conversion experiments presented that the derivatives of the LDH calcination are promising materials to be used in the AOP. The formation of a ZnAl2O/ZnO nanocomposite from calcination at 850 °C showed the best conversion results from the coupling semiconductors for charge separation strategy that diminish some problems associated with charge carrier recombination and its higher UV absorbance. Thus, the results show the multi-functionality of these materials, giving some light to the discussion about LDH recovery by "memory effect" that remains a topic of intense debate in the literature.
FAPESP: 2013/25043-4
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19

Gasparini, Mirthys Cozzett. "Águas de processo da REPLAN = qualidade e aplicação de processos oxidativos avançados." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257779.

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Orientadores: José Roberto Guimarães, Carlos Gomes da Nave Mendes
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
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Resumo: No presente trabalho foi realizada a caracterização de várias correntes de águas de processo da REPLAN (Refinaria de Paulínia), bem como a avaliação dos processos de fotólise (UV), peroxidação (H2O2), peroxidação assistida por radiação ultravioleta (H2O2/UV), reagente de Fenton (H2O2/Fe2+) e foto-Fenton (H2O2/Fe2+/UV) no tratamento de um dos efluentes, principalmente na degradação dos compostos orgânicos. Analisando-se os dados de caracterização dos diferentes efluentes foi possível sugerir alternativas de reuso no processo de refino, como também selecionar a corrente de água ácida retificada para aplicação dos processos físico-químicos de tratamento. A eficiência dos ensaios de tratabilidade foi baseada na redução da concentração do carbono orgânico dissolvido (COD). Dentre os processos estudados, os processos oxidativos avançados (POA) H2O2/UV e foto-Fenton apresentaram 95 % de eficiência após 150 minutos de ensaio. As condições ótimas foram obtidas na relação mássica COD: H2O2 de 1:7 para o processo peroxidação assistida por radiação UV, e de 1:5 e concentração de Fe2+ de 31 mg/L para o processo foto-Fenton. O efluente tratado pelo processo H2O2/UV poderia ser reutilizado como água de reposição no sistema de resfriamento, já que esta é responsável por 49 % do total de água utilizada na refinaria
Abstract: In the present study was performed the characterization of various process water from REPLAN (Paulínia Refinery) as well as an assessment of 5 processes to treat one of the effluents: photolysis (UV), peroxidation (H2O2), peroxidation assisted by ultraviolet radiation (H2O2/UV), Fenton reagent (H2O2/Fe2+) and photo-Fenton (H2O2/Fe2+/UV), in order to degrade the organic compounds. Effluents characterization results provided reuse possibilities in the process refining and also selected the stripped sour water stream for application of physical-chemical treatments. The processes efficiency was evaluated by the dissolved organic carbon (DOC) reduction. Among the processes studied, the advanced oxidation processes (AOPs) H2O2/UV and photo-Fenton reached 95 % efficiency after 150 minutes of reaction. The optimum conditions were obtained in a mass ratio COD: H2O2 of 1:7 for peroxidation assisted by UV radiation, and of 1:5 with 31 mg/L of Fe2+ for photo-Fenton. The effluent treated by AOP H2O2/UV could be reused as make-up water in cooling systems, since it is responsible for 49 % of the total water used in the refinery
Mestrado
Saneamento e Ambiente
Mestre em Engenharia Civil
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20

Matysíková, Jana. "Znovu-užití vyčištěných odpadních vod v papírenském a textilním průmyslu." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225374.

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This thesis deals with Advanced oxidation processes (AOP) and its aplication for textile wastewaters treatment and reuse. AOP is a modern technology which currently recieves increased attention due to it´s high efficiency in removing resistant and hardly-degradable pollution. Thesis consists of search and practical part. Search part is created by three chapters. First chapter describe briefly wastewater reuse. The second chapter deals with Advanced oxidation processes. AOP principle, AOP division and descriotion is included with the strong focus on the ozonation technology. The third chapter presents the textile industry and its wastewaters. The practical part of this thesis consists of two chapters. Chapter 5 describes testing of textile wastewaters decoloration by ozonation in the selected textile copany and its results. This results are used in chapter 6. Chapter 6 is the study of textile industry treatment and reuse in the selected textile company. This study contains the design of two options for wastewater treatment and reuse in the textile processes.
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21

Pirgalioglu, Saltuk. "Catalytic Ozonation Of Dye Solutions In A Semi-batch Reactor." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12610158/index.pdf.

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Treatment of textile wastewaters containing dye materials using the conventional methods based on biological treatment is not possible. In order to overcome this problem, ozonation based on the oxidation of organic pollutants with ozone gas dissolved in aqueous phase have been studied widely. Catalytic ozonation and advanced oxidation processes (AOP) are also used in order to increase the efficiency of sole ozonation In this work, catalytic ozonation processes in the presence of Copper Sulfide (CuS) powder and a synthesized catalyst by the impregnation of iron on alumina (Fe/Al2O3) were studied separately in the treatment of dye solutions, namely Remazol Brilliant Blue-R (RBBR) and Reactive Black-5 (RB-5). Besides catalytic ozonation runs, ozonation parameters and ozonation mechanism were also studied and a model was developed for the semi-batch ozonation. Both catalysts increased the oxidation of side products measured by the decrease in the amount of total organic carbon (TOC) in the treated dye solutions. Dye removal rates were also enhanced in the treatment of RB-5 dye solutions while no significant effect was observed on dye removal rates of RBBR solutions. TOC removals above 90% were observed in the catalytic ozonation using CuS for both of the dye solutions at pH =10 having initial dye concentration of 100 mg/L. The most significant effect of the catalyst addition was observed at pH = 3 where the TOC removals of non-catalytic ozonation were the lowest. CuS addition increased percent TOC removal at the end of the reaction period of 80 min by 123% in the treatment of 100 mg/L RBBR solution, and by 65% in the treatment of 100 mg/L RB-5 solution at pH = 3. On the other hand, addition of Fe/Al2O3 catalyst increased TOC removal of 100 mg/L RB-5 solution by 52 % at pH = 3. In addition, volumetric mass transfer coefficients (kLa) of ozone in the absence and in the presence of a chemical reaction between dye and ozone were estimated from modeling. A correlation for the enhancement factor of ozone absorbed into dye solutions in terms of initial dye concentration was obtained and reported.
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22

Metolina, Patrícia. "Degradação do antibiótico bacitracina zí­ncica em meio aquoso através de processos oxidativos avançados." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-24092018-082606/.

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A presença de antibióticos no ecossistema representa um sério risco à saúde humana e animal em virtude do desenvolvimento crescente de resistência bacteriana. Uma vez que a maioria dos antibióticos é persistente à degradação biológica, os processos oxidativos avançados são apontados como uma das tecnologias mais efetivas para decompor esses compostos em águas residuárias. A bacitracina zíncica (Bc-Zn) é um potente antibiótico constituído por uma mistura complexa de peptídeos não-biodegradáveis, conjugados ao zinco. Apesar de ser um antibiótico amplamente consumido na medicina humana e animal, é preocupante a escassez de estudos que investigam sua degradação e destino ambiental. O presente trabalho analisou a degradação da Bc-Zn através dos processos de fotólise direta e UV/H2O2 em diferentes condições de radiação UVC e concentração inicial de H2O2. Os parâmetros cinéticos rendimento quântico da fotólise, constantes cinéticas de pseudo-primeira ordem e constante cinéticas de segunda ordem foram satisfatoriamente estimados pela modelagem do sistema fotoquímico experimental. Os resultados revelaram que a fotólise direta permitiu degradar todos os congêneres da mistura de Bc-Zn nas maiores doses de radiação UVC empregadas. No entanto, não houve remoção de TOC após 120 minutos de irradiação. A adição de H2O2 acelerou substancialmente a fotodegradação do antibiótico, apresentando constantes cinéticas de pseudo-primeira ordem uma ordem de grandeza superiores às obtidas por fotólise direta. Além disso, remoção considerável de até 71% do TOC foi alcançada. A análise estatística demonstrou que a radiação UV foi um fator bem mais significativo para a fotodegradação da Bc-Zn em relação à concentração inicial de H2O2, sendo as melhores condições do processo alcançadas para a maior taxa específica de emissão de fótons (1,11×10-5 Einstein L-1 s-1). Ensaios biológicos com soluções tratadas por fotólise direta e UV/H2O2 indicaram remoção completa da atividade antimicrobiana residual, ainda que os produtos da fotodegradação tenham se mostrado não-biodegradáveis. Análises de toxicidade indicaram que o metal zinco presente no antibiótico é responsável pela a toxicidade no micro-organismo-teste Vibrio fischeri. Estudos adicionais devem ser realizados para identificar os sub-produtos formados, bem como para investigar a degradação da Bc-Zn em efluentes industriais reais.
The presence of antibiotics in ecosystems represents a serious risk to human and animal health, caused by the increase in bacterial resistance. Since most antibiotics resist to biological degradation, advanced oxidation processes are pointed out as the most effective technologies for degrading these compounds in wastewater. Zinc bacitracin (Bc-Zn) is a potent antibiotic with a complex mixture of non-biodegradable peptides conjugated to zinc. Despite being a widely used antibiotic in human and animal medicine, the scarcity of studies dealing with its degradation and environmental fate is a matter of concern. In this work, Bc-Zn degradation by direct photolysis and the UV/H2O2 process was investigated for different UVC radiation conditions and initial H2O2 concentrations. Kinetic parameters, namely the photolysis quantum yield, pseudo-first order kinetic constants and second-order kinetic constants, were satisfactorily estimated from experimental data by modeling the photochemical system. The results showed that all the congeners of the Bc-Zn mixture were photolyzed at the highest UVC doses applied, while no TOC removal was observed after 120 minutes of irradiation. The addition of H2O2 substantially accelerated Bc-Zn photodegradation, with pseudo-first order kinetic constants of one order of magnitude higher than those observed under direct photolysis. In addition, a remarkable removal of up to 71% of TOC was achieved. Statistical analyses showed that UV radiation had a much more important effect on Bc-Zn photodegradation in comparison with initial H2O2 concentration, with the best process conditions achieved for the highest specific photon emission rate (1.11×10-5 Einstein L-1 s-1). Biological assays carried out with the solutions treated by direct photolysis and UV/H2O2 revealed no residual antimicrobial activity, though photodegradation products remained non-biodegradable. In addition, toxicity analyses indicated that the zinc metal present in the antibiotic is responsible for the toxic effect on the test microorganism Vibrio fischeri. Finally, further studies should be performed to identify the by-products formed and to investigate Bc-Zn degradation in real industrial wastewater.
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Oliveira, Clélia Aparecida da Silva 1972. "Tratamento de corante têxtil por eletrólise, fotólise e fotocatálise utilizando LED UV = Treatment of textile dye by electrolytic, photolytic and photocatalytic processes." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267750.

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Orientador: Peterson Bueno de Moraes
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Tecnologia
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Resumo: A indústria têxtil gera elevados volumes de efluentes com alta carga orgânica e compostos recalcitrantes, os quais são tratados por sistemas baseados em processos físicos, químicos e biológicos convencionais. Entretanto, o caráter não destrutivo dos tratamentos convencionais representa um sério problema no setor. Nos últimos 20 anos, os Processos Oxidativos Avançados (POA) têm estado em evidência devido à sua capacidade em degradar inúmeros compostos orgânicos contidos em águas e efluentes. Uma grande quantidade de trabalhos utilizando luz UV a partir de lâmpadas de vapor de mercúrio tem resultado em elevada eficiência de degradação de substratos recalcitrantes incluindo efluentes têxteis; entretanto, demandam elevado consumo de energia elétrica, encarecendo o tratamento. Em contrapartida, o surgimento de Diodos Emissores de Luz Ultravioleta (LED UV) abre novas fronteiras de aplicação no campo de tratamento de águas residuárias, quanto a custo, operacionalidade e tamanho dos sistemas. Nesse trabalho estudou-se a degradação de um efluente têxtil simulado contendo o corante Remazol Azul Brilhante (C.I. Reactive Blue 19) através de processos eletroquímicos e fotoeletroquímicos que utilizam LED UV, utilizando-se dois reatores: um operando em batelada contendo o fotocatalisador TiO2 e o outro, em fluxo, contendo um cátodo (tela cilíndrica de aço-inoxidável), um tubo de quartzo contendo os LED UV e o Anodo Dimensionalmente Estável (ADE 70%TiO2/30%RuO2). Os resultados demonstraram que, no reator de bancada, a eficiência de remoção de cor foi de 100% para concentração inicial de 50 mg L-1 do corante, em 24 horas de tratamento. No reator em fluxo, utilizando Na2SO4 como eletrólito, o processo eletrolítico resultou em eficiência de 65%; o fotoeletrocatalítico, em 68%, operando a 750 L h-1 e em 57,3 mA cm-2. Quando foi utilizado o eletrólito NaCl, obteve-se remoção de 100% da cor em 5 minutos de tratamento a 750 L h-1, independente da concentração inicial do corante utilizada (50 mg L-1 ou 100 mg L-1), da concentração do eletrólito (0,05 M ou 0,1 M), da densidade de corrente (14,3 mA cm-2 , 28,7 mA cm-2 ou 57,3 mA cm-2) e do processo utilizado
Abstract: The textile industry generates large amount of wastewater containing significant organic load and recalcitrant compounds, which in most cases are treated by conventional systems involving physical, chemical and biological processes, the latter represented mainly by activated-sludge treatment. However, the non-destructive profile of conventional treatments is a serious problem for textile-based industry. Over the past 20 years, the study of Advanced Oxidation Processes (AOP) has been carried out due to its high capacity degradation of numerous organic pollutants contained in waters and wastewaters. Research using UV light from mercury vapor lamps usually has resulted in high efficiency degradation of recalcitrant substrates including textile effluents but requires high electrical power consumption besides other drawbacks. In contrast, the emergence of Ultraviolet Light Emitting Diodes (UV LED) opens new perspectives for application on wastewater treatment, concerning efficiency, footprint and costs of the systems. In this work we studied the degradation of a simulated wastewater containing a textile dye, Remazol Brilliant Blue (C.I. Reactive Blue 19) through electrochemical and photoelectrochemical processes using UV LED as ultraviolet radiation source. The experimental apparatus consisted of two systems: the first, a bench-scale reactor containing TiO2 photocatalyst (P25 DEGUSSA) in solution, and another pilot-scale system operated in batch recirculation mode composed of an tubular stainless-steel screen cathode, a quartz tube containing the UV LED and a oxide-coated titanium anode (DSA©30%TiO2/70%RuO2). The results showed total decolorization of a solution containing 50 mg L-1 of RB in 24-hour treatment in the bench-scale reactor. Tests on flow reactor using Na2SO4 as supporting electrolyte resulted in 65% of color removal using electrolytic process and 68% for photoelectrocatalytic process operating at 750 L h-1 and 57.3 mA cm-2. In experiments using the electrolyte NaCl it was obtained 100% in the color degradation within 5 minutes of treatment at 750 L h-1, regardless of the: initial concentration of dye used (50 mg L-1; 100 mg L-1), concentration of the electrolyte (0.05 M; 0.1 M) and current density value (14.3; 28.7; 57.3 mA cm-2)
Mestrado
Tecnologia e Inovação
Mestra em Tecnologia
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24

Fujimoto, Tânia Miyoko 1985. "Oxidação de compostos orgânicos voláteis em fase gasosa por fotocatálise heterogênea com TiO2 e TiO2/Pd." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266077.

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Orientador: Edson Tomaz
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: Compostos orgânicos voláteis (COV) representam uma categoria de substâncias poluentes que geram diferentes impactos ambientais. Eles são responsáveis pelo aumento das concentrações de ozônio ao nível do solo e pela formação de aerossóis orgânicos secundários. Além disso, alguns deles contribuem para a degradação do ozônio estratosférico e a ampliação do efeito estufa. Alguns componentes têm um caráter carcinogênico, teratogênico ou mutagênico. Há estudos envolvendo o tratamento dos COV pelos mais diversos métodos, tais como: incineração, adsorção e absorção. Reatores fotocatalíticos, muito estudados em aplicação em fase aquosa e com grande sucesso na oxidação de contaminantes orgânicos, aparecem como uma alternativa pouco estudada. A fotocatálise em fase gasosa usando o TiO2 como catalisador se apresenta como uma solução interessante para o tratamento de compostos orgânicos voláteis, por não requerer operação em altas temperaturas, pelo baixo custo do TiO2, por ser seletiva na absorção de radiação e por gerar como produtos da reação CO2 e água, o que dispensa demais tratamentos. Estudos demonstram que a adição de metais nobres ao TiO2 comprova uma melhoria na eficiência fotocatalítica das reações de oxidação de compostos orgânicos voláteis. Dentro deste escopo, este trabalho tem como objetivo testar a eficiência do processo de oxidação de COV em fase gasosa por fotocatálise heterogênea com catalisador de dióxido de titânio (TiO2) impregnado com 1% de paládio (Pd) sob luz ultravioleta. O método de impregnação de paládio em TiO2 pela redução com NaBH4 mostrou-se adequado pelas técnicas de caracterização por DRX, XPS, UV ¿Vis, BET, MEV e Quimissorção de H2, pois há a impregnação do metal na superfície do catalisador sem promover modificações estruturais no TiO2 e não ocorreu alterações na razão de anatase/rutilo. Por XPS indicou a presença de metal em sua forma elementar. Além disso, os resultados da oxidação dos compostos n-hexano, ciclohexano, metil-ciclohexano, n-octano e iso-octano demonstraram aumento significativo na eficiência da conversão, pois foram obtidos valores acima de 90% em tempos de residência de aproximadamente 35 s
Abstract: Volatile organic compounds (VOCs) represent a category of pollutants substances that generate different impacts. They are responsible for increase concentrations of tropospheric ozone and also the formation of secondary organic aerosols. In addition, some of them contribute to the degradation of stratospheric ozone and greenhouse gas intensification. Some components have a carcinogenic, teratogenic or mutagenic character. There are studies involving the treatment of VOCs with various methods, such as: incineration, adsorption and absorption. Photocatalytic reactors, extensively studied in aqueous and with great success to destroy organic contaminants, appears as an alternative understudied. The photocatalysis gas phase using TiO2 as catalyst shows an interesting solution for the treatment of volatile organic compounds, because does not require operation at high temperatures, the low cost of TiO2, being selective in absorbing radiation and the products of reactions are CO2 and water, which eliminates other treatments. Studies prove that the addition of noble metals on TiO2 can improve the photocatalytic efficiency in the oxidation of volatile organic compounds. Therefore, this paper aims to test the efficiency of oxidation of volatile organic compounds (VOC) in gas phase catalysts through heterogeneous photocatalysis with titanium dioxide (TiO2), and their impregnation with 1% palladium (Pd) and UV light. The method for impregnate palladium on TiO2 with NaBH4 reduction was appropriated according to techniques for characterization like XRD, XPS, UV-vis, BET, SEM and H2 chemisorption, because all analysis confirmed that the impregnation of the metal on the catalyst surface do not structurally modify TiO2, neither changes occurred in the ratio of anatase/rutile. XPS indicated the presence of metal in elemental form. The results the oxidation of compounds n-hexane, cyclohexane, methyl cyclohexane, n-octane and iso-octane indicated a significant increase in conversion efficiency; the values were above 90% at residence times around 35 s
Mestrado
Desenvolvimento de Processos Químicos
Mestra em Engenharia Química
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25

Nogueira, Maria Ionete Chaves. "Tratamentos adsortivos e de oxidaÃÃo avanÃada de fenol, 2-nitrofenol e 4-nitrofenol em soluÃÃo aquosa." Universidade Federal do CearÃ, 2009. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=4106.

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FundaÃÃo de Amparo à Pesquisa do Estado do CearÃ
Neste trabalho foram realizados estudos de adsorÃÃo em batelada e de oxidaÃÃo avanÃada para a remoÃÃo de fenol (F), 2-nitrofenol (2NF) e 4-nitrofenol (4NF) em soluÃÃo aquosa. Nos estudos de adsorÃÃo foram empregados como adsorventes o pà de bagaÃo da casca de coco in natura (BIN), pà de bagaÃo in natura tratado com HCl 1,0 M (BT) e carvÃo ativado (CA) proveniente da carbonizaÃÃo a 250ÂC do pà de bagaÃo tratado com Ãcido. Experimentos de equilÃbrio e cinÃtica de adsorÃÃo foram realizados nas temperaturas de 28, 40 e 50ÂC. Isotermas de Langmuir e Freundlich correlacionaram bem os dados de equilÃbrio, indicando capacidades de adsorÃÃo (qmÃx) que aumentaram na ordem: CA >>> BT > BIN. Este comportamento denota uma adsorÃÃo caracterizada pelas interaÃÃes entre os elÃtrons  dos anÃis aromÃticos e os elÃtrons  das camadas grafÃticas do carvÃo, a qual à mais intensa que a verificada nos materiais celulÃsicos onde predomina a formaÃÃo de complexos doador-receptor entre os sÃtios oxigenados localizados na superfÃcie do adsorvente e o anel aromÃtico dos compostos fenÃlicos. Os melhores resultados de qmÃx em carvÃo ativado e pà de bagaÃo tratado com Ãcido foram obtidos para a adsorÃÃo de 2-nitrofenol à temperatura ambiente (28ÂC), correspondentes aos valores de 17,1 e 1,39 mg/g, respectivamente. Do ponto de vista cinÃtico o modelo de pseudo-segunda ordem apresentou melhor ajuste dos dados experimentais. Por outro lado, processos oxidativos avanÃados (POAs) das molÃculas fenÃlicas foram conduzidos para os tratamentos fotolÃtico (UV), fotoquÃmico (UV/H2O2), Fenton (Fe2+/H2O2) e eletroquÃmico com anodos dimensionalmente estÃveis (ADEs) de Ru0,3Ti0,7O2, Ru0,3Ti0,4Sn0,3O2 e Ru0,3Sn0,7O2. Os processos Fenton e fotoassistidos apresentaram condiÃÃes Ãtimas nas concentraÃÃes de 1,0 mM em Ãons Fe2+e 3,0 mM em H2O2 e taxa de radiaÃÃo (I0) de 64 mW/cm2. Os Ãxidos eletrocatalÃticos foram preparados por termodecomposiÃÃo de cloretos precursores a 500oC atà a formaÃÃo de filmes com 2,0 Âm de espessura sobre um suporte de titÃnio. A caracterizaÃÃo pelas tÃcnicas de EDX, MEV e Voltametria CÃclica mostrou composiÃÃes praticamente estequiomÃtricas, morfologia estrutural tipo cracked mud e elevado sobrepotencial para a reaÃÃo de desprendimento de oxigÃnio (RDO). Estudos de oxidaÃÃo para as molÃculas fenÃlicas mostraram o 2-nitrofenol como a espÃcie mais oxidÃvel e o fenol comum como a espÃcie menos reativa. As eficiÃncias de degradaÃÃo dos processos fotoassistidos foram particularmente elevadas (superiores a 80%) enquanto o sistema Fenton apresentou taxas de remoÃÃo entre 60 e 78%. A modelagem cinÃtica segundo o modelo de pseudo-primeira ordem adotado permitiu um bom ajuste dos dados experimentais. Os valores da constante cinÃtica 1/ (min-1) a 28ÂC mostraram a seguinte ordem: Fenton (8,16 min-1) > fotoquÃmico (6,95 min-1) >> fotolÃtico (1,98 min-1). Em adiÃÃo, estudos usando anodos eletrocatalÃticos (ADEs) a potencial constante de eletrÃlise de 2,0 V mostraram degradaÃÃes superiores a 93% para os nitrofenÃis e entre 65 e 86% para o fenol. Em termos, considerado o tipo de ADE empregado, a eficiÃncia de eletrooxidaÃÃo à temperatura ambiente obedece a seguinte ordem de eficiÃncia: Ru0,3Ti0,7O2 > Ru0,3Ti0,4Sn0,3O2 > Ru0,3Sn0,7O2. A anÃlise espectroscÃpica para identificaÃÃo de co-produtos indicou completa mineralizaÃÃo dos compostos fenÃlicos nos processos fotoquÃmico e eletroquÃmico, enquanto que nos processos Fenton e fotolÃtico foram detectados traÃos de produtos hidroxilados. Em geral, os resultados obtidos confirmam os processos adsortivos e oxidativos como tratamentos promissores para a despoluiÃÃo de sistemas aquosos contendo fenÃis e nitrofenÃis
In the present work the batch adsorption and advanced oxidation of phenol (F), 2-nitrophenol (2NF) and 4-nitrophenol (4NF) in aqueous phase has been studied. The adsorption experiments were conducted onto coconut shell powder (BIN), coconut shell powder treated with HCl 1.0M (BT) and coconut shell-based activated carbon (CA) obtained from carbonization at low temperature (250ÂC). Equilibrium and kinetic studies were carried out at temperatures of 28, 40 and 50ÂC. Langmuir and Freundlich isotherms correlated well the equilibrium data, indicating the adsorption capacity (qmax) increased in the order: AC>>> BT> BIN. This behavior denotes an adsorption characterized by dispersive interactions between the -electrons of the graphitic carbon basal planes and those of the aromatic rings of the adsorbate, which is more intense when compared to the cellulose materials where are dominant the donor-acceptor complex formation between the oxygenated sites onto adsorbent and aromatic rings of phenol compounds. The best results of qmax in activated carbon and coconut shell powder treated with acid were obtained for the adsorption of 2-nitrophenol at room temperature (28ÂC), corresponding to values of 17.1 and 1.39 mg/g, respectively. In all cases, the adsorption kinetics could be satisfactorily fitted by a pseudo-second order model. Advanced oxidation processes (AOP) were carried out for treatments such photolytic (UV), photochemical (UV/H2O2), Fenton (Fe2+/H2O2) and electrochemical oxidation with dimensionally stable anodes (DSA) type Ti/Ru0.3Ti0.7O2, Ti/Ru0.3Ti0.4Sn0.3O2 and Ti/Ru0,3Sn0,7O2. The Fenton and photoassisted tests were performed to optimized conditions of 1.0 mM of Fe2+ ions, 3.0 mM of H2O2 and radiation intensity (I0) of 64 mW/cm2. Particularly, electrocatalytic oxides were prepared by thermal decomposition of chloride precursors to 500oC until the formation of films with thickness constant of 2μm on titanium support. The characterization by EDX, SEM and Cyclic Voltammetry techniques showed a nearly stoichiometric composition, morphology type âcracked mudâ and elevated overpotencial from oxygen evolution reaction (OER). Degradation efficiencies in photoassisted processes were particularly high (> 80%) while in the Fenton system this values ranged between 60 and 78%. The kinetic modelling using the equation of pseudo-first order adopted allowed a good fit of experimental data. The values of kinetic constant 1/ (min-1) at room temperature showed the following order: Fenton (8.16 min-1) > Photochemical (6.95 min-1) >> photolytic (1.98 min-1). In addition, studies using the electrocatalytic anodes at constant potential electrolysis of 2.0 V showed almost total degradation for the nitrophenols (> 93%) and moderate removal efficiencies for phenol (between 65 and 86%). In terms, considered the type of anode employed the electrooxidation efficiency at room temperature increase in the following order of reactivity: Ru0.3Ti0.7O2 > Ru0.3Ti0.4Sn0.3O2 > Ru0.3Sn0.7O2. Thus, the results confirm the applicability of adsorption and advanced oxidation processes as promising treatments in the remediation of aqueous systems containing phenol and nitrophenols
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Acosta, Arlen Mabel Lastre. "Processos de tratamento não convencionais para degradação do antibiótico sulfadiazina em meio aquoso." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-22082016-102752/.

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A presença de antibióticos no meio ambiente aquático tem causado crescente preocupação mundial. Além dos relatos de resistência de bactérias a antibióticos, essa classe de fármacos também pode causar efeitos tóxicos e atuar como perturbadores endócrinos em diversos organismos vivos e, possivelmente, em humanos. Dentre os antibióticos comumente usados destacam-se as sulfonamidas, detectadas em águas subterrâneas e superficiais. Os processos avançados de oxidação (POA) têm sido apontados como tecnologias eficientes para tratamento de poluentes recalcitrantes em diferentes matrizes aquosas. Dentre os POA, o processo foto-Fenton é uma alternativa para a degradação de compostos não biodegradáveis, incluindo fármacos. Uma vez que a principal limitação do processo é o intervalo de pH (2,5- 4,0), a reação pode ser vantajosamente conduzida empregando-se substâncias bio-orgânicas solúveis (BOS) como agentes complexantes de Fe3+ em condições ligeiramente ácidas (pH 5). Por sua vez, o emprego da energia ultrassônica tem sido menos estudado. Nesse contexto, o objetivo deste trabalho é estudar a degradação do antibiótico sulfadiazina (SDZ) por meio do processo foto-Fenton na presença de substâncias bio-orgânicas solúveis (UVvis/ Fe3+/H2O2/BOS) e do processo de cavitação por meio de ultrassom (US). Os resultados obtidos mostram que a sulfadiazina é eficientemente degradada por ultrassom de alta frequência. As maiores porcentagens e taxas de remoção são obtidas usando menor frequência de operação (580 kHz), maior potência dissipada e em pH ligeiramente ácido (melhor condição: pH 5,5). Além disso, a reação de Fenton, combinada com o tratamento US, melhorou notavelmente a degradação da SDZ, particularmente quando quantidades extras de H2O2 foram adicionadas ao sistema. Por sua vez, o uso de BOS como aditivos no processo foto-Fenton apresenta influência marcante na fotodegradação da SDZ em condições ligeiramente ácidas (pH 5). Os BOS podem estabilizar espécies de ferro em solução aquosa em pH próximos ao neutro, o que constitui uma propriedade de grande interesse. Sob as condições estudadas, o BOS CVT230 foi mais eficiente do que FORSUD, provavelmente devido às diferenças nos grupos funcionais presentes na composição destas substâncias. Finalmente, foram calculados os indicadores de consumo de energia elétrica por ordem de grandeza (EEO) para o processo de ultrassom (1572 kW h m-3 ordem-1) e área do coletor por ordem de grandeza (ACO) para o processo foto-Fenton (8,07 m2 m-3 ordem-1).
The potential impacts of antibiotic residues in the environment have become an emerging concern during recent years due to their relation with the development of resistant bacteria, and in some cases to their ability to cause toxic and endocrine disrupting effects in humans and other living organisms. Highlighted among the commonly used antibiotics are the sulfonamides, detected in groundwater and surface water. Advanced oxidation processes (AOP) might constitute an important alternative to deal with pharmaceuticals degradation. Among them, the photo-Fenton process has been widely used. One of its major drawbacks is the highly acidic pH needed (2,5-4,0) to avoid the formation of photochemically inactive iron oxides and hydroxides. The ability of soluble bio-organic substances (SBO) to complex metal cations such as iron is useful for the development of photo-Fenton at mild acidic conditions (pH 5). In turn, the use of ultrasonic energy has been less studied. In this context, the aim of this work is to study the degradation of the antibiotic sulfadiazine (SDZ) by the photo-Fenton process in the presence of soluble bio-organic substances (UV-vis/Fe3+/H2O2/SBO) and by ultrasonic cavitation (US). The results confirm that SDZ is effectively degraded by highfrequency ultrasound. Higher SDZ percent removals and removal rates were observed for the lowest operating frequency (580 kHz), higher dissipated power, and in slightly acidic solution (pH 5.5). On the other hand, SDZ degradation is highly improved in the case of the US/ Fe(II)/H2O2 system. The use of the SBO as Fenton additives in turn has a remarkable influence in SDZ photodegradation at slightly acid conditions (pH 5). This could be ascertained to the complexation of iron by the SBO, hence maintained in the reaction medium as a photoactive species. Under the studied conditions, the BOS CVT230 was more efficient than FORSUD, probably due to differences in the functional groups present in the composition of these substances. Finally, the figures-of merit electrical energy per order (EEO) and collector area per order (ACO) were calculated for the ultrasound (1572 kW h m-3 ordem-1) and photo-Fenton (8,07 m2 m-3 ordem-1) processes respectively.
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Baptistucci, Cíntia Bardauil. "Degradação do antibiótico ciprofloxacina em solução aquosa por meio de processo oxidativo avançado baseado em ozônio." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-03052012-122334/.

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Os tratamentos convencionais de efluentes em geral não são eficientes para a degradação de compostos persistentes como os fármacos. Neste trabalho, estuda-se o tratamento de soluções aquosas contendo o antibiótico ciprofloxacina (CIP) por meio de processo oxidativo avançado baseado em ozônio. Para tanto, foram realizados experimentos em semi-batelada com recirculação de líquido em um reator (coluna de bolhas) com escoamento gás-líquido em contracorrente. Amostras de líquido foram retiradas e analisadas para medida das concentrações de CIP e de carbono orgânico total (COT); a concentração de ozônio no gás foi medida por espectrofotometria UV-vis. Estudaram-se os efeitos das seguintes variáveis quanto à degradação de CIP, por meio de um planejamento Doehlert: concentração de ozônio à entrada do reator (8-25 mgO3 L-1), pH (3,5-10,5) e concentração inicial de CIP (5-26 mg L-1). Avaliaram-se as seguintes variáveis dependentes por meio da análise de superfícies de resposta: variação de concentração de CIP em 2 minutos; taxa inicial de degradação de CIP e variação de concentração de COT em 30 minutos. Os resultados indicaram total degradação de ciprofloxacina em menos de 15 minutos, tanto por via direta, com ataque por ozônio molecular em meio ácido, como por via indireta, com ataque por radicais hidroxila em meio básico. Os compostos resultantes da degradação da CIP mostraram-se recalcitrantes, obtendo-se maiores remoções de COT após 30 minutos apenas em meio básico ou neutro (máximo de 72,8% para pH=7, [O3]=24,9 mgO3 L-1 e [CIP]0=15,8 mg L-1). Apesar da persistência dos compostos orgânicos remanescentes, os ensaios respirométricos sugeriram que os produtos de degradação são menos tóxicos que o composto de partida, com menor inibição da atividade microbiana. No conjunto, os resultados do trabalho indicam que o processo de ozonização pode ser aplicado para pré-tratamento de efluentes aquosos contendo ciprofloxacina em baixas concentrações, podendo ser associado a processos de tratamento biológico em ETEs antes do descarte.
Conventional wastewater treatment processes are not generally efficient for the degradation of persistent substances like pharmaceutical compounds. In this work, the treatment of aqueous solutions containing the antibiotic ciprofloxacin (CIP) by means of the ozone-based advanced oxidation process is studied. With this aim, experiments were carried out in semi-batch mode with liquid circulation in a bubble column reactor with gas-liquid counter flow. Liquid samples were analyzed for CIP and total organic carbon (TOC) concentrations; ozone concentration in the gas was measured by UVvisible spectrophotometry. The effects of the following variables on CIP degradation were studied according to a Doehlert experimental design: inlet ozone concentration (8 to 25 mgO3 L-1), pH (3.5 to 10.5), initial CIP concentration (5 to 26 mg L-1). The following dependent variables were investigated by response surface analysis: variation in CIP concentration after 2 minutes; CIP initial degradation rate and variation in TOC concentration after 30 minutes. The results showed total degradation of ciprofloxacin in less than 15 minutes either by direct reaction with molecular ozone in acidic medium, or by indirect attack of hydroxyl radicals in alkaline medium. Compounds resulting from CIP degradation showed to be recalcitrant, yielding larger TOC removals after 30 minutes only in alkaline or neutral medium (maximum of 72.8% for pH=7, [O3]=24.9 mgO3 L-1, and [CIP]0=15.8 mg L-1). Despite the persistence of remaining organic compounds, respirometric assays suggested that degradation products are less toxic than the parent compound, exhibiting lower inhibition of microbial activity. Overall, the results indicate that the ozonation process can be used in the pre-treatment of aqueous effluents containing ciprofloxacin in low concentrations, and could be associated with biological treatment processes in wastewater treatment plants prior to final disposal.
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D\'Avila, Alexandre Coelho da Silva. "Degradação do pesticida amicarbazona em meio aquoso pelo processo TiO2/UV irradiado por luz solar." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-03072013-105850/.

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Os processos oxidativos avançados (POAs) têm sido apontados como alternativa eficiente para a degradação de poluentes recalcitrantes. Entre os POAs, a fotocatálise utilizando luz solar vem sendo muito estudada tendo em vista sua aplicação no tratamento de efluentes aquosos contendo pesticidas. No presente trabalho, estudou-se a degradação do herbicida amicarbazona (AMZ) por meio do processo TiO2/UV em um reator com coletores parabólicos compostos irradiados por luz solar. Os experimentos foram realizados segundo uma matriz Doehlert para o estudo da influência da concentração inicial de AMZ (20-100 mg L-1), da concentração de catalisador (0,1-1 g L-1) e do número de tubos expostos à luz solar (1-9). Amostras retiradas ao longo do tempo foram analisadas quanto às concentrações de AMZ e de carbono orgânico total (TOC). As medidas radiométricas realizadas indicaram que a radiação UVB-UVA correspondeu em média a ca. 4% da radiação solar total incidente entre 310-2800 nm; a actinometria de ferrioxalato indicou fluxo fotônico médio de 3,58×10-5 mol fótons m-2 s-1 para dias ensolarados típicos. O processo TiO2/UV mostrou-se eficiente para degradação do pesticida, que foi totalmente removido antes de 45 minutos de tratamento, para as seguintes condições: [AMZ]0=21,3 mg L-1; [TiO2]=0,5 g L-1; e 7 tubos. Contudo, nesse caso houve apenas ca. 24% de mineralização e na grande maioria dos casos os valores de TOC permaneceram praticamente constantes, o que indica a formação de sub-produtos recalcitrantes, cuja toxicidade e biodegradabilidade devem ser caracterizadas. A análise estatística dos resultados confirma os efeitos importantes da concentração inicial do pesticida e do número de tubos expostos (volume irradiado), cujo aumento permite compensar a menor incidência de radiação solar. Em alguns experimentos os resultados sugeriram que a degradação da AMZ foi favorecida pela maior concentração de TiO2. Na grande maioria dos casos os valores de ACM foram inferiores a 50 m2 kg-1, o que torna este parâmetro interessante para aumento de escala de processos fotocatalíticos irradiados por luz solar empregados no tratamento de efluentes aquosos contendo amicarbazona.
Advanced oxidative processes (AOP) have been considered as an efficient alternative for the degradation of recalcitrant pollutants. Photocatalysis using solar radiation has been studied for the treatment of wastewaters containing pesticides. In this work, the degradation of the herbicide amicarbazone (AMZ) by the TiO2/UV process was studied in a reactor equipped with compound parabolic collectors irradiated by solar light. The experiments were carried out according to a Doehlert matrix to study the effects AMZ initial concentration (20-100 mg L-1), catalyst concentration (0.1-1 g L-1), and number of tubes exposed to solar light (1-9). Samples were analyzed for AMZ and total organic carbon (TOC) concentrations. Radiometric measurements indicated that UVB-UVA radiation corresponded in average to about 4% of the solar radiation between 310-2800 nm; ferrioxalate actinometry resulted in an average photonic flux of 3.58×10-5 mol fótons m-2 s-1 for typical sunny days. The TiO2/UV process showed to be efficient for the degradation of the pesticide, which was completely removed before 45 minutes of treatment, for the following conditions: [AMZ]0=21.3 mg L-1; [TiO2]=0.5 g L-1; and 7 tubes. However, in this case only ca. 24% of mineralization was achieved, and in most cases TOC values remained practically constant, indicating the formation of recalcitrant by-products whose toxicity and biodegradility should be characterized. Statistical analysis of the results confirmed important effects of pesticide initial concentration and number of tubes exposed (irradiated volume), whose increase enables to compensate the lower incidence of solar radiation. Some experimental results suggested that AMZ degradation was favored by higher TiO2 concentrations. In most cases the values of ACM were lower than 50 m2 kg-1, in such a way that this parameter is interesting for scale-up of solar irradiated photocalytic processes used in the treatment of amicarbazone-containing wastewaters.
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Ferrando, Climent Laura. "Analysis of chemotherapy drugs and related compounds in aquatic environment: removal, transformation and risk evaluation in eco-friendly and advanced technologies." Doctoral thesis, Universitat de Girona, 2016. http://hdl.handle.net/10803/400719.

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In order to evaluate the increasing environmental and human risk of anticancer drugs in the environment, more information needs to be gathered about their presence, their toxicity, bioaccumulation and persistence. In addition, their removal performance in conventional wastewater treatment facilities and in alternative treatments needs further investigation efforts. The aim of this thesis is to fill knowledge gaps and provide tools for a better assessment about the presence and fate of anticancer drugs in the urban water cycle. The work presented hereby includes three main objectives: i) to develop analytical methodologies for target and non-target analysis of anticancer drugs in aquatic environment, ii) to assess the occurrence of anticancer drugs in urban systems and iii) to appraise different technological alternatives to remove anticancer drugs from polluted effluents
Per tal d'avaluar l'augment de risc ambiental i humà de medicaments contra el càncer en el medi ambient, més informació necessita ser recopilada sobre la seva presència, la seva toxicitat, bioacumulació i persistència. A més, la seva capacitat d'eliminació d'aigües residuals en plantes de tractament convencionals i en tractaments alternatius necessita a investigacions addicionals. L'objectiu d'aquesta tesi és omplir els buits de coneixement i proporcionar eines per a una millor avaluació de la presència i el destí dels medicaments contra el càncer en el cicle urbà de l'aigua. El treball presentat per aquest mitjà inclou tres objectius principals: i) desenvolupar metodologies analítiques per a la meta i anàlisi que no són objecte de medicaments contra el càncer a medi aquàtic, ii) per avaluar l'ocurrència de medicaments contra el càncer en els sistemes urbans i iii) per avaluar diferents alternatives tecnològiques a eliminar medicaments contra el càncer d'efluents contaminats
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30

Abouzlam, Manhal. "Optimisation d'un procédé de traitement des eaux par ozonation catalytique." Thesis, Poitiers, 2014. http://www.theses.fr/2014POIT2251/document.

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Le principal objectif de la thèse est l'optimisation d'un procédé d'oxydation avancée par la mise en œuvre des outils de l'automatique moderne.Le procédé considéré concerne l'ozonation catalytique utilisé pour traiter les eaux résiduaires industrielles. L'optimisation de ce procédé consiste à contrôler l'abattement des polluants tout en minimisant le coût de fonctionnement du procédé. La mesure en ligne de la concentration en polluant est fournie par l'absorbance, grandeur corrélée à la DCO. Le procédé est alors considéré comme un système à une entrée, la puissance du générateur d'ozone, et deux sorties, l'ozone dans les évents et l'absorbance.L'identification du procédé a mené à l'estimation d'un modèle linéaire pour construire les lois de commande et d'un modèle non-linéaire, de type modèle de Wiener, pour tester les correcteurs en simulation avant les essais expérimentaux.Les trois commandes testées, la commande par modèle interne, la commande optimale et la commande H∞, permettent de rejeter des perturbations sur la concentration en polluant dans les effluents à traiter. Des analyses de stabilité du système bouclé, vis-à-vis de retards sur la commande, ont été menées.Les résultats expérimentaux obtenus ont permis de conclure sur les gains significatifs apportés par ces développements.La méthodologie développée pour cette application peut être étendue à d'autres procédés afin de faciliter le développement industriel des procédés d'oxydation avancée
The main goal of the PhD thesis focuses on the optimization of an advanced oxidation process by implementing the modern control tools.The considered process is a lab-scale pilot of industrial wastewater treatment by catalytic ozonation. The optimization of this process is achieved by controlling the pollutant abatement while minimizing the high operating costs. The online measurement of the pollutant concentration is provided by the absorbance which is correlated with COD. Therefore, the process is considered as a system with one input, the ozone generator power, and two outputs, the ozone gas concentration at the top of the reactor and the absorbance.A linear model of the process was identified. It allowed calculating the control laws. And a nonlinear model, with a so-called Wiener model structure, was also identified to test the controllers in simulation before the experiments.The three control methods applied, the internal model control, the optimal control and the H∞ control, allow rejecting disturbance on the pollutant concentration of the effluent to be treated.The stability of closed-loop system with delayed control input was analyzed.The experimental results show the significant benefits provided by this closed-loop system.The methodology developed for this application can be extended to other processes to facilitate the industrial development of advanced oxidation processes
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31

Autin, Olivier. "Micropollutant removal by advanced oxidation processes." Thesis, Cranfield University, 2012. http://dspace.lib.cranfield.ac.uk/handle/1826/7883.

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The use of pesticides in agriculture has been associated to high concentrations found in surface waters and ultimately to the tightening of drinking water regulations. Whilst traditional granular activated carbon filtration or ozone are effective barriers for the large majority of pesticides, new polar pesticides such as clopyralid or metaldehyde are not readily removed by such technologies. The use of advanced oxidation processes (AOPs) is suggested as an effective alternative for metaldehyde removal. Although metaldehyde’s reactivity towards •OH appears in the last third of an extensive list of various pesticides’ reactivity, it was still well removed by the two AOPs tested: UV/H2O2 and UV/TiO2 in pure systems at similar rates of degradation under optimised doses of 100 mg.L-1 of TiO2 and 8 mM of H2O2. The presence of scavengers in natural waters such as natural organic matter (NOM) and carbonate ions reduced the effectiveness of metaldehyde removal. Experiments were undertaken using model compounds in order to evaluate the influence of these scavengers by directly monitoring the competition for •OH between background organic matter and metaldehyde. It was found that the concentration of background scavengers rather than the concentration of micropollutant had the greatest impact on both AOPs. In addition, whilst the alkalinity did not significantly influence the UV/H2O2 process, it totally inhibited the UV/TiO2 photocatalytic process due to the aggregation of TiO2 particles and further investigations are critical in order to break these aggregates for UV/TiO2 photocatalysis to become a competitive alternative to traditional treatments. Finally, a cost analysis showed that AOPs already appear as an economically viable technology for metaldehyde removal. Development of UV/LEDs will provide a lower energy option which will be economically competitive within the next 7-8 years.
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32

Mirjana, Petronijević. "Uticaj oksidacionih procesa na bazi ozona, vodonik-peroksida i UV zračenja na sadržaj i reaktivnost prirodnih organskih materija u vodi." Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 2019. https://www.cris.uns.ac.rs/record.jsf?recordId=110672&source=NDLTD&language=en.

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Cilj  istraživanja  u  okviru  ove  doktorske  disertacije  je  utvrđivanje  efekata  različitihoksidacionih procesa na bazi ozona, vodonik-peroksida i UV zračenja na sadržaj i reaktivnost prirodnih  organskih  materija  (POM)  u  različitim  vodenim  matriksima.  Ispitivanja  su sprovedena  na  a)  podzemnoj  vodi  sa  teritorije  Kikinde  i  Temerina  (prirodni  matriks)  i  b) sintetičkom  vodenom  matriksu  (rastvoru  komercijalno  dostupne  huminske  kiseline),  koji  se među sobom razlikuju po sastavu i strukturi prisutne POM i sadržaju bromida. Za oksidacioni proces  (ozonizacija,  UV  fotoliza,  oksidacija  sa  H 2O2,  kombinovani  O 3 /UV  proces  i kombinovani  H 2O2/UV  proces)  pojedinačno  ispitan  je  uticaj  različitih  doza  oksidanata  i reakcionih  uslova.Posebna  pažnja  posvećena  je  ispitivanju  uticaja  navedenih  tretmana  naformiranje  neorganskog  bromata,  kao  i  uticaja  na  sadržaj  prekursora   dezinfekcionih nusproizvoda nakon hlorisanja (THM, HAA, HAN, HK i CP).Analiza  hemijskih  parametara  sintetičkog  matriksa  (5,44±0,30  mg  C/l; 0,255±0,015 cm -1 ;  4,68±0,41  lm -1 mg -1 )  pokazuje  da  u  njemu  preovladavaju  huminnske materije  visoke  hidrofobnosti.  Visok  sadržaj  POM  pretežno  hidrofobnog  karaktera  je zabeležen i u vodi iz Kikinde (5,170,72 mg C/l; 0,2010,001 cm   -1   ; 3,88±0,70 lm  -1  mg -1 ), dok je  sadrža j  POM  u  sirovoj  vodi  iz  Temerina  (2,060,38  mg  C/l;  0,0500,001  cm   -1    ; 2,43±0,21 lm  -1  mg -1   ) značajno niži i preovladavaju POM hidrofilnog karaktera. Veći stepen hidrofobnosti sintetičkog matriksa u poređenju sa  prirodnim matriksima, rezultovao  je  i  većom  reaktivnosti  organske  materije  sa  hlorom,  što  se  može  zaključiti  naosnovu visokih vrednosti PFDBP nakon hlorisanja. Vrednost PFTHM u sintetičkom matriksu iznosi  544±85,9  µg/l,  dok  je  PFTHM  u  kikindskoj  i  temerinskoj  sirovoj  vodi  znatno  niži (279±32,3  i  180±44,0  µg/l,  respektivno).  Vrednost  PFHAA  u  sintetičkom  matriksu  iznosi 484±77,5 µg/l, dok je PFHAA u kikindskoj 244±11,1 µg/l i u temerinskoj vodi 165±32,5 µg/l. Sadržaj  HK  (8,05±3,63  µg/l  sintetički  matriks;  14,91,38  µg/l  Kikinda;  7,400,25  µg/l Temerin)  je  znatno  niži  u  poređenju  sa  prekursorima  THM  i  HAA,  dok  prekursori  HAN  i hlorpikrina  nisu  detektovani  u  sirovoj  vodi.  Nusproizvodi  koji  se  dominantno  formiraju  u svim  ispitivanim  vodenim  matriksima  su  hlorovani  THM  i  HAA,  dok  se  bromovani  DBPformiraju u znatno nižim koncentracijama. Zastupljenost bromovanih DBP u temerinskoj vodije  znatno  veći  u  poređenju  sa  vodom  iz  Kikinde,  kao  rezultat  prisustva  veće  koncentracije bromida u sirovoj vodi (0,05±0,01 mg Br -/l Temerin; 0,03±0,01 mg Br-/l Kikinda). Ispitivanjem  uticaja  oksidacionih  procesa  (UV  fotolize,  ozonizacije,  oksidacije vodonik-peroksidom)  na  sadržaj  i  reaktivnost  POM  u  ispitivanim  vodenim  matriksima utvrđeno  je  da  tretman  vode  UV  zračenjem  i  vodonik-peroksidom,  kada  se  primenjuju  kao samostalan  tretman,  ne  pokazuju  značajnu  efikasnost  u  smanjenju  sadržaja  POM.Tretman vode  ozonom  se  pokazao  kao  veoma  efikasan  u  uklanjanju  POM  i  u  smanjenju  sadržaja prekursora  DBP  kod  svih  ispitivanih  vodenih  matriksa,  kao  rezultat  smanjenja  reaktivnosti POM  ka  formiranju  ovih  DBP.  Smanjenje  sadržaja  POM  u  vodi  tokom  tretmana  raste  sa povećanjem  primenjene  doze  ozona,  pri  čemu  se  najbolji  rezultati  postižu  pri  najvećoj primenjenoj  dozi  od  3,0  mg  O 3/mg  DOC  (do  32%  DOC,  92%  UV254 sintetički  matriks;  do 17%  DOC,  76%  UV 254  Kikinda;  do  15%  DOC  i  66%  UV254    Temerin).  U  sintetičkom matriksu  najveće  smanjenje  PFTHM  (za  76%)  i  PFHAA  (za  80%)  u  odnosu  na  sadržaj  u sirovoj vodi se postiže pri dozi od 1,0  mg O3 /mg DOC. Najveće smanjenje PFTHM (za 38%)i PFHAA (za 42%) u vodi iz Kikinde postiže se pri dozi od 3,0 mg O 3 /mg DOC. U vodi iz Temerina najveće smanjenje PFTHM (za  27%) je pri dozi od 3,0 mg O 3 /mg DOC, dok se za smnjenje  PFHAA  (za  54%)  najbolje  pokazala  doza  od  1,0  mg  O3 /mg  DOC.  Sadržaj prekursora  HK  i  HAN  (temerinska  voda)  je  veoma  nizak  nakon  tretmana.  Tretman  vode ozonom  vodi  ka  formiranju  DBP  sa  više   supstituisanih  atoma  broma,  dok  u  vodama  sa srednjim sadržajem bromida (50 µg Br -/l) dovodi do formiranja bromata. Kombinacijom  ozonizacije  sa  UV  zračenjem  se  značajno  može  pospešiti  efiksnost uklanjanja  POM  postignuta  primenom  samostalne  ozonizacije.  Najveće  smanjenje  sadržaja POM u  sintetičkom matriksu (za 85% DOC, 98% UV254 i 87% SUVA), u vodi iz Kikinde (za23% DOC, 83% UV 254, 77% SUVA), i vodi iz Temerina (za 15% DOC, 80% UV254 i 75% SUVA), u odnosu na vrednosti u netretiranoj vodi postignuto je pri najvećoj primenjenoj dozi od  3,0  mg  O 3 /mg  DOC  i  6000  mJ/cm 2 .  Efikasnost  procesa  raste  u  vodama  u  kojima preovladavaju  POM  veće  hidrofobnosti.  MeĎutim,  iako  se  O 3 /UV  procesom  postiže  visok stepen  smanjenja  PFTHM  u  sintetičkom  matriksu  se  najbolje  pokazao  tretman  ozonom (1,0 mg  O3/mg  DOC),  dok  se  najveće  smanjenje  PFHAA  (82%)  postiže  pri  dozi  ozona  od 1,0 mg O3/mg DOC i UV zračenja od 6000 mJ/cm 2 . U vodi iz Kikinde se PFTHM smanjuje za 50% pri dozi od 3,0 mg O 3/mg DOC i 6000 mJ/cm 2 , dok se u slučaju uklanjanja prekursoraHAA  ozonizacija  pokazala  kao  superiorniji  proces.  U  vodi  iz  Temerina  se  u  pogledu uklanjanja  prekursora  THM  i  HAA  ozonizacija  pokazala  kao  optimalan  proces.  Visok alkalitet  prirodnih  voda  inhibira  radikalski  mehanizam  u  toku  AOP  i  favorizuje  oksidaciju POM molekulskim ozonom.  Prekursori HK se formiraju u  veoma niskim koncentracijama i njihov sadržaj ne varira značajno tokom tretmana. U prirodnim matriksima tokom AOP pri dozi  ozona  od  3,0 mg  O3 /mg  DOC  dolazi  do  formiranja  HAN,  međutim,  nije  uočen  jasan trend  sa  povećanjem  doze  UV  zračenja.  Tretman  doprinosi  formiranju  bromovanih  vrsta THM,  dok  se  tokom  AOP  pri  najvećoj  dozi  ozona  od  3,0 mg  O3 /mg  DOC  formiraju bromovani HAN.Najveće  smanjenje  sadržaja  POM  primenom  kombinacije  oksidacije  sa  H 2O2i  UV zračenja u sintetičkom matriksu (za do 17% DOC, 70% UV 254 ), u vodi iz Kikinde (za do 22% DOC, 53% UV254), i vodi iz Temerina (za do 7% DOC, 68% UV254 ), u odnosu na vrednosti u sirovoj vodi, se postižu pri dozi H 2O2 i UV zračenja od 3,0 mg H2O2/mg DOC i 6000 mJ/cm 2 .Najveće  smanjenje  PFTHM  od  54%  u  sintetičkom  matriksu  se  postiže  pri  dozi  od 0 mg H2O2/mg DOC i 6000 mJ/cm 2 ,  dok se smanjenje PFHAA (za 35%)  postiže primenom doze vodonik-peroksida i UV zračenja od 1,0 mg H 2O2 /mg  DOC i 3000 mJ/cm 2 . U vodi izKikinde  H2O2 /UV  proces  ne  utiče  značajno  na  sadržaj  prekursora  THM,  dok  se  najveće smanjenje  PFHAA  (za  35%)  postiže  pri  dozi  od  3,0  mg  H  2 O2/mg  DOC  i  600  mJ/cm 2 .H 2 O2 /UV  proces  dovodi  do  smanjenja  PFTHM  u  Temerinskoj  vodi  za  74%  pri  dozi  od 3,0 mg H2O2/mg DOC i 600 mJ/c m 2 ,  dok primenjeni tretman ne pokazuje značajan uticaj naPFHAA.  Prekursori HK su detektovani u sintetičkom matriksu i temerinskoj vodi u niskim koncentracijama.  U  temerinskoj  vodi  nakon  AOP  pri  dozi  vodonik-peroksida  od 3,0 mg H2O2 /mg DOC dolazi  do formiranja HAN i hlorpikrina. Primenjeni tretman vodi ka formiranju bromovanih DBP. Svi rezultati dobijeni u toku istraživanja ukazuju na neophodnost optimizacije procesa u  tretmanu  ispitivanih  vodenih  matriksa  i  određivanja  optimalnog  procesa uzimajući  u  obzirkarakteristika  sirove  vode  i  efikasnost  koja  se  želi  postići.Kombinacijom  dva  i  više konvencionalnih  tretmana  i  optimizacijom  reakcionih  uslova  može  se  postići  visoka efikasnost uklanjanja POM, kao i ciljano uklanjanje prekursorskog materijala odabranih DBP, međutim  tretman  vode  ozonom  pri  dozi  od  1,0 mg  O3/mg  DOC  se  pokazao  kao  optimalan proces.
The aim of the research  of  this  PhD thesis  was  to determine the effects of various oxidation processes based on ozone, hydrogen peroxide and UV irradiation on the content and reactivity of natural organic matter  (NOM)  in different water matrices. The  tests were carried out  on  a)  groundwater  from  the  territory  of  Kikinda  and  Temerin  (natural  matrix)  and  b) synthetic aqueous matrix (solution of commercially available humic  acid), which differ in the composition  and  structure  of  NOM  present  and  the  content  of  bromide.  For  the  oxidation process  (ozonation,  UV  photolysis,  oxidation  with  H 2O2 ,  combined  O 3 /UV  process  and combined  H 2O2 /UV  process),  the  influence  of  different  doses  of  oxidants  and  reaction conditions  was  examined  individually.  Particular  attention  was  paid  to  the  influence  of  the above treatment on the formation of inorganic bromate, as well as the effect on the content of precursors of disinfectant by-products after chlorination (THM, HAA, HAN, HK and CP).Analysis  of  the  chemical  parameters  of  the  synthetic  matrix  (5.44±0.30  mg  C/L; 0.255±0.015 cm -1 ;  4.68±0.41  lm -1 mg -1 )  shows  that  the  high-hydrophobic  humic  compounds predominate in this water. Also, high NOM content of predominantly hydrophobic character was recorded in Kikinda water (5.170.72 mg C/L; 0.2010.001 cm -1 ;  3.88±0.70 lm -1 mg -1 ), while  NOM  content  in  raw  water  from  Temerin  (2.060.38  mg  C/L;  0.0500.001  cm -1 ; 2.43±0.21 lm -1 mg -1 ) significantly lower and predominate NOM of hydrophilic character. A higher degree of hydrophobicity of the synthetic matrix in comparison with  natural matrices, resulted in higher reactivity of organic matter with chlorine, which can be concluded on  the  basis  of  high  PFDBP  values  after  chlorination.  The  PFTHM  value  in  the  synthetic matrix  was  544±85.9 µg/L, while the PFTHM in the raw waters from Kikinda and Temerin was  significantly  lower  (279±32.3  and  180±44.0  µg/L,  respectively).  The  PFHAA  value  in the  synthetic  matrix  was  484±77.5  µg/L,  while  PFHAA  in  the  Kikinda  water  was 223 244±11.1 µg/L  and in  the  Temerin  water  was  165±32.5 µg/L.  The content of  precursors of HK  (8.05±3.63  µg/L  synthetic  matrix;  14.91.38  µg/L  Kikinda;  7.400.25  µg/L  Temerin) was  significantly  lower  compared  to  precursors  of  THMs  and  HAAs,  while  precursors  of HANs  and  chloropicrin  were  not  detected  in  raw  water.  The  by- products  that  were predominantly  formed  in  all  the  tested  water  matrices  were  chlorinated  THMs  and  HAAs, while the brominated DBPs  were  formed at substantially lower concentrations. The presence of  brominated DBPs  in  Temerine  water  were  significantly higher compared to Kikinda water as  a  result  of  the  presence  of  higher  bromide  content  in  raw  water  (0.05±0.01  mg  Br -/L Temerin; 0.03±0.01 mg Br -/L Kikinda). By  examining  the  influence  of  oxidation  processes  (UV  photolysis,  ozonation,hydrogen  peroxide  oxidation)  on  the  content  and  reactivity  of  NOM  in  the  tested  water matrix, it was  found that the UV  irradiation and  treatment by  hydrogen peroxide, when used as an independent treatment, did  not show significant efficacy in reducing the  NOM content. Water treatment by ozone  proved to be very effective in eliminating  NOM and reducing the content of DBP precursors in all tested water  matrices, as a result of the reduction of  NOM reactivity   to  the  formation  of  these  DBPs.  Reduction  of  NOM  content  in  water  during treatment increased  with increasing the applied dose of ozone, with the best results achieved at the highest dosage of  3.0 mg O 3/mg DOC  (up to 32% DOC, 92% UV 254  synthetic matrix, up  to  17%  DOC,  76%  UV 254 Kikinda,  up  to  15%  DOC  and  66%  UV254 Temerin).  In  the synthetic  matrix the highest reduction  in  PFTHM (76%) and PFHAA (by 80%)  compared to raw water content  was  achieved at a dosage  of 1.0 mg O 3/mg DOC. The highest reduction in PFTHM  (38%)  and  PFHAA  (42%)  in  Kikinda  water  was  achieved  at  a  dose  of 3.0 mg O3 /mg DOC. In Temerin water, the highest reduction in PFTHM (27%) was at a dose of  3.0 mg O 3/mg DOC, while the dose of 1.0  mg O3 /mg  DOC  was best shown for removing PFHAA (by 54%). The content of the precursors of HKs and HANs (Temerin water) was very low  after  treatment.  Water  treatment  by  ozone  led  to  the  formation  of  DBPs  with  more substituted bromine atoms, while in waters with a mean bromide content (50 μg Br -/L) led  to bromate formation.Combination of ozonation with UV irradiation can greatly accelerate the effectiveness of  NOM  removal  achieved  by  the  use  of  ozonation  alone.  The  highest  reduction  in  NOM content in the synthetic matrix (by 85% DOC, 98% UV 254 and 87% SUVA), in Kikinda water (by 23%  DOC, 83% UV 254 , 77% SUVA) and water from Temerin (by 15% DOC, 80% UV 254 and 75% SUVA), compared to the values in  raw  water, was achieved at the highest  dose of 3.0  mg  O 3 /mg  DOC  and  6000  mJ/cm 2 .  The  efficiency  of  the  process  was  growing  in  the waters where NOM predominates of hydrophobicity. Although the O 3 /UV process achieved a high  degree  of  reduction  in  PFTHM  in  the  synthetic  matrix  the  ozonation (1.0 mg O3 /mg DOC)  was  proved  as  more  efficient,  while  the  highest  reduction  in  PFHAA (82%)  was  achieved  at  a  ozone  dose  of  1.0  mg  O 3/mg  DOC  and  UV  irradiation  of 6000 mJ/cm 2 . In the water from Temerin,  in case to removal of precursors of THM and HAA, ozonation  was proved  to be an optimal process. High alkalinity of natural waters  inhibits the radical   mechanism  during  AOP  and  favors  NOM  oxidation  with  molecular  ozone.  HKs precursors were formed at very low concentrations and their content did not vary significantly during  the  treatment.  In  natural  matrices  during  the  AOP  at  a  ozone   dose  of 3.0 mg O3 /mgDOC, HANs  were  formed, however, there  was  no clear trend with increasing UV irradiation. The treatment contributed to the formation of brominated THM species, while during  the  AOPs,  brominated  HANs  were  formed  at  the  maximum  dose  of  ozone  of 3.0 mg O3/mg DOC. 224 The largest decrease in  NOM content by the combination of oxidation with H2O2 and UV irradiation in the synthetic matrix (for up to 17% DOC, 70% UV 254 ), in Kikinda water (up to 22% DOC, 53% UV 254), and water from Temerin  (7% DOC, 68% UV 254 ), compared  to the values  in  raw  water,  were  obtained  at  a  dose  of  H 2O2 and  UV  irradiation  of 3.0 mg O3 /mg DOC  and 6000 mJ/cm 2 . The highest PFTHM reduction of 54% in the  synthetic matrix was achieved at a dosage of 1.0 mg H2O2/mg DOC and 6000 mJ/cm 2 , while a decrease in  PFHAA  (35%)  was  achieved  using  a  dose  of  hydrogen  peroxide  and  UV  irradiation  of 1.0 mg H2O2/mg DOC and 3000 mJ/cm 2 . In the water from Kikinda, the H2O2 /UV process did not significantly affect on the THM precursors content, while the highest reduction in PFHAA (35%)  was  achieved  at  a  dose  of  3.0  mg  H2O2/mg  DOC  and  600  mJ/cm 2 .  The  H 2O2 /UV process  led  to  a  decrease  in  PFTHM  in  the  Temerin  water  by  74%  at  a  dose  of 3.0 mg  2O2 /mg  DOC  and  600  mJ/cm 2 ,  whereas  the  treatment  applied  had  no  significant effect on PFHAA. HKs precursors were detected in synthetic matrix and the Temerin water at low  concentrations.  In  the  water  after  the  AOP  at  a  dose  of  3.0  mg  H 2O2 /mg  DOC  of hydrogen  peroxide,  HANs  and  chloropicrin  were  formed.  The  applied  treatment  led  to  the formation of brominated DBPs.All the results obtained during the research indicate the necessity of optimization  the process  in  the  treatment  of  the  examined  water  matrices  and  determination  of  the  optimal process taking into account the characteristics of  raw water and the efficiency to be achieved. By combining two or more conventional treatments and optimizing the reaction conditions, high  NOM removal efficiency can be achieved, as well as removal of the  targeted  precursor material  of  the  selected  DBPs,  but  the  treatment  of  ozone  water  at  a  dose  of 1.0 mg O3 /mg DOC was proved to be an optimal process.
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33

Sevilla, Esparza Cindy Jocelyn. "Efficacy of Catalytic Ozonation Advanced Oxidation Processes Compared to Traditional Ozone-Based Advanced Oxidation Processes for Degradation of Recalcitrant Compounds." DigitalCommons@CalPoly, 2020. https://digitalcommons.calpoly.edu/theses/2207.

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This study reviews catalytic ozonation AOPs and traditional ozone-based AOPs to compare their efficiency for degradation of ozone-recalcitrant compounds. With the world’s population increasing and water becoming a scarce resource, it is important to improve current water recycling methods. Recycling water will play a large role in accommodating the increasing demand, but it will also be necessary to be improve the level of treatment in order to account for emerging contaminants (ECs) such as pharmaceuticals and personal care products. Advanced oxidation processes (AOPs) have been developed to degrade ECs that are not effectively removed by conventional wastewater treatment. The goal of implementing AOPs is to promote the formation of hydroxyl radicals (•OH), which are stronger oxidants than ozone, to degrade recalcitrant compounds. Current AOPs under investigation include ozonation of metal and carbon-based catalysts, known as catalytic ozonation. Traditional ozone-based AOPs currently in use include UV combined with ozone (UV/O3) and hydrogen peroxide combined with ozone (H2O2/O3). Seventeen studies were reviewed to analyze the effectiveness of multiple carbon- and metal oxide-catalytic ozonation AOPs, compared to traditional AOPs. These studies varied in reactor type, water source, pH, catalyst pretreatment, inclusion of competitor species, and flow regime. The variety of testing conditions made comparison difficult, so all studies were compared based on contaminant removal efficiency and degradation rate, as well as general EC degradation and removal of TOC. The addition of metal oxides during ozonation consistently increased rate of removal and in some cases, even doubled the reaction rate. Catalytic ozonation consistently decreased total organic carbon (TOC) levels amongst multiple studies, even in the presence of competitor species. Future work should study the formation and subsequent breakdown of reaction intermediates, role of competitor species, and impact of sorption to the ozonation catalyst.
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34

Escalona, Hernández Ivonne Graciela. "Membrane-assisted advanced oxidation processes for wastewater treatment." Doctoral thesis, Universitat Rovira i Virgili, 2014. http://hdl.handle.net/10803/284445.

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El bisfenol A (BPA) i la tartrazina (TAR) pertanyen al grup de compostos que són potencialment nocius per a la recuperació d'aigües residuals. El BPA és un disruptor del sistema hormonal o disruptor endocrí, mentre que la TAR és un colorant azoic. Una diversitat d'indústries, especialment la indústria paperera i tèxtil, produeixen un gran volum d'aigües residuals que estan contaminades amb BPA i colorants. Per tant, els efluents que contenen tant BPA com colorants han de ser gestionats de manera eficient amb la finalitat d'evitar problemes ambientals vinculats a ells. Durant l'última dècada, s’han assajat diversos mètodes per a l'eliminació de BPA i TAR d'aigües residuals, resultant ser eficaços i potencialment aplicables a gran escala. No obstant això, la majoria d'ells encara enfronten problemes de costos, la qual cosa exigeix el seu desenvolupament. La nanofiltració (NF) ofereix una solució adequada per a l'eliminació de BPA i colorants de les solucions aquoses, degut a la seva capacitat per retenir substàncies orgàniques dissoltes. És per això que en aquest treball de tesi, es va utilitzar la NF en flux tangencial mitjançant membranes polimèriques per eliminar BPA i TAR de solucions aquoses. Addicionalment, la degradació de BPA i TAR durant els tractaments per Fenton, ozonación i enzimàtic sota diferents condicions d'operació, en combinació amb la seva posterior NF van ser assajats. Resultats indiquen que tant el BPA com la TAR poden ser eficientment degradats per aquests processos. L'ús d'un sistema integrat membrana-reactor va mostrar el potencial i les limitacions de l'ús dels processos d'oxidació avançada en conjunt amb membranes de NF per a la remoció del BPA i de la TAR. En general elevades eficiències de remoció van ser aconseguides amb les diferents membranes de NF utilitzades.
Bisfenol A (BPA) y tartrazina (TAR) pertenecen al grupo de compuestos que son potencialmente dañinos para la recuperación de aguas residuales. BPA es un perturbador del sistema hormonal o disruptor endocrino, mientras que la TAR es un colorante azo. Variedad de industrias, especialmente la industria papelera y textil producen un gran volumen de aguas residuales que están contaminadas con BPA y colorantes. Por lo tanto, los efluentes que contiene tanto BPA como colorantes, deben ser gestionados de manera eficiente con la finalidad de evitar problemas ambientales vinculados a ellos. Durante la última década, varios métodos para la eliminación de BPA y TAR de aguas residuales han sido probados, resultando ser eficaces y potencialmente aplicables a gran escala. Sin embargo, la mayoría de ellos todavía enfrentan problemas de costes, lo cual exige su desarrollo. La nanofiltración (NF) ofrece una solución adecuada para la eliminación de BPA y colorantes de las soluciones acuosas debido a su capacidad para remover sustancias orgánicas disueltas. Es por ello que en esta tesis, la NF en flujo cruzado usando membranas poliméricas fue utilizada para remover BPA y TAR de soluciones acuosas. Adicionalmente, la degradación de BPA y TAR durante los tratamientos por Fenton, ozonación y enzimático bajo diferentes condiciones de operación, en combinación con su posterior NF fueron ensayados. Resultados indican que tanto el BPA como la TAR pueden ser eficientemente degradados por estos procesos. El uso de un sistema integrado membrana-reactor mostró el potencial y las limitaciones del uso de los procesos de oxidación avanzada en conjunto con membranas de NF para la remoción del BPA y de la TAR. En general elevadas eficiencias de remoción fueron alcanzadas con las diferentes membranas de NF utilizadas.
Bisphenol A (BPA) and tartrazine (TAR) belong to the compounds which are potentially harmful during wastewater reclamation. BPA is a typical Endocrine Disrupting Chemical and TAR is an azo dye. Variety of industry, especially paper and textile industries produces a large volume of wastewater that is polluted with BPA and dyes. Therefore, BPA and dyes-charged effluents need to be efficiently managed in order to avoid environmental problems linked to them. During the last decade, several methods for BPA and TAR removal of wastewater have been found effective and potentially applicable for scaling up. However, most of them still face cost problems, thus demanding further development. It is generally accepted that nanofiltration (NF) offers an adequate solution for the removal of BPA and dyes from the aqueous solutions owing to its capacity to remove dissolved organics. In the present thesis, crossflow NF using thin film composite polymeric membranes were applied to reject BPA and TAR from aqueous solutions. Additionally, the degradation of BPA and TAR during Fenton’s, ozonation and enzymatic processes under different operational conditions, in combination with subsequent NF of low concentration remnant BPA and TAR and compounds derived from oxidation was investigated. Results indicate that BPA and TAR could be degraded efficiently in aqueous phase by Fenton, ozonation and enzymatic processes. The use of a membrane-reactor integrated system for BPA and TAR degradation demonstrated the potential and limitations of using advance oxidation processes, operated in a recycling mode coupled to a NF membrane. In general, high BPA and TAR removal efficiencies for several NF membranes were achieved.
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35

Yalfani, Mohammad Sadegh. "New catalytic advanced oxidation processes for wastewater treatment." Doctoral thesis, Universitat Rovira i Virgili, 2011. http://hdl.handle.net/10803/34768.

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En cuanto a la mejora de los Procesos de Oxidación Avanzada para el tratamiento de aguas residuales, se han diseñado y estudiado nuevos procesos catalíticos Fenton y ozonización catalítica para la eliminación de contaminantes orgánicos del agua. El proceso Fenton se ha realizado mediante peróxido de hidrógeno generado in situ, el cual se ha producido a partir de ácido fórmico y oxígeno sobre un catalizador de paladio soportado en alúmina. A continuación, se ha heterogeneizado totalmente el sistema utilizando un catalizador bimetálico Pd-Fe y se ha aplicado con éxito en la degradación de diferentes categorías de contaminantes orgánicos. La combinación de este proceso de oxidación con hidrodecloración ha obtenido una alta eficiencia en la degradación de clorofenoles. En cuanto al uso de diferentes sustitutos de H2, se ha observado una mayor eficiencia de la hidroxilamina en el proceso Fenton con generación in situ de peróxido de hidrógeno para efluentes neutros. Con respecto al desarrollo de nuevos materiales para ozonización catalítica, se ha estudiado la degradación de compuestos farmacéuticos mediante catalizadores de cobre-dawsonita. El cobre incorporado en la estructura de dawsonita presenta una mayor actividad en la ozonización catalítica con respecto a la muestra calcinada, cobre en solución y óxido de cobre soportado en alúmina.
Regarding to the improvement of Advanced Oxidation Processes for wastewater treatment, new catalytic Fenton process and catalytic ozonation were designed and studied in the removal of organic pollutants from water. Fenton process was performed using in situ generated hydrogen peroxide, which was produced from formic acid and oxygen over alumina-supported palladium catalyst. Then, the system was fully heterogenized by using bimetallic Pd-Fe catalyst and applied successfully for different categories of organic pollutants. The combination of the above oxidation process with hydrodechlorination led to high efficiency in the degradation of chlorophenols. The performance of different hydrogen substitutes in the Fenton process using in situ generated hydrogen peroxide showed higher efficiency of hydroxylamine for neutral solutions. Concerning the development of new catalytic materials for catalytic ozonation, the degradation of pharmaceutical compounds was performed using dawsonite-derived copper catalysts. The copper incorporated into the structure of dawsonite indicated higher activity in catalytic ozonation with respect to the calcined sample, soluble copper and aluminasupported copper oxide.
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36

Bach, Altai. "Water purification by advanced oxidation processes using nano particles." Online version, 2010. http://dds.crl.edu/CRLdelivery.asp?tid=13238.

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37

Romero, Olarte Rossmary Violette. "Degradation of metoprolol by means of advanced oxidation processes." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/294150.

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For this study the emerging contaminant ß-blocker Metoprolol (MET) has been selected due that it is a highly prescribed pharmaceutical and it has been detected in waste water treatment plants influents, thus, in natural waters. Several studies, focused on the toxicological potential of Metoprolol, indicate its potential environmental relevance and its recalcitrant nature. To remove MET from water, different Advanced Oxidation Processes (AOPs) were used. MET removal was studied, in different reactors with natural and artificial light, by photolysis, UVC/H2O2, photocatalysis, Fenton, photo-Fenton, bicarbonate-activated hydrogen peroxide (with cobalt or iron) processes. The different set-ups and technologies tested have been compared in order to establish the efficiency of the processes. The experiments were normally carried out with 50 mg/L of initial MET in Milli-Q water, free pH, and 25 ± 5 ºC. Thus, photolysis experiments were done in (solarbox (SB), Compound Parabolic Collector (CPC), Black light blue lamps (BLB) and UVC254 nm (UVC) reactors). The best result obtained was 93.5% of MET removal in UVC reactor after 240 minutes. UVC/H2O2 experiments were carried out in UVC reactor. Different H2O2 concentrations and pH were tested and the maximum removals were MET (98%) and TOC (70.7%) for 125 mg H2O2/L. Photocatalysis was carried in SB and CPC with different TiO2 concentrations (0.05, 0.10 and 0.40 g /L). Experiments were also carried out varying the initial MET concentration (25, 50 and 100 mg/L), pH and the water matrix with 0.4 g TiO2/L in SB or adding 25 and 150 mg/L of H2O2. The best results obtained were a complete MET removal and 45.7% of mineralization in SB and 81.5% of MET degradation and 29.2% of mineralization in CPC. The dark-Fenton experiments were carried out at pH in a reactor of 2 L. Two different concentrations of Fe (II) (2.5 mg/L or 10 mg/L) and H2O2 (25 mg/L or 150 mg/L) were used. To improve the Fenton process, the total Iron (II) concentration was divided in equal parts (5) and added at constant periods of time (12 minutes) during 1 hour. With the highest concentrations of iron and H2O2 the maximum MET conversion was 87.0% and mineralization 15.6%. Photo-Fenton experiments were done at pH 3, and temperature of 14 or 25 ºC in four reactors (BLB, SB, CPC and UVC). Two different concentrations of Fe (II) (2.5 mg/L or 10 mg/L) and H2O2 (25 mg/L or 150 mg/L) were used. With the highest iron and H2O2 concentrations, the best results in MET degradation were observed (BLB: 100% in 7 min; SB: 97.3% in 7 min; CPC: 98.3% in 3 min). The dark- Bicarbonate/hydrogen peroxide experiments were carried out with 5 mg/L of MET in drinking water, pH 6.2, and room temperature in a reactor of 0.5 L. To improve the process, cobalt (II) or iron (II) as catalyzer were added in the batch reactor. A complete MET conversion in 40 minutes was achieved. The efficiency of different AOPs and reactors tested was compared from the ratio between accumulated energy and MET eliminated. The energy is better used in CPC (0.065 kJ/mg) than in SB (0.275 kJ/mg). For photo-Fenton process (0.04 kJ/mg) UVC and (0.05 kJ/mg) BLB reactors exhibit a much better performance than (0.30 kJ/mg) SB and (0.26 kJ/mg) CPC reactors. From the intermediates identified, a possible MET fragmentation was proposed for the different processes, where, mainly oxidative attacks were detected. On the other hand, the irradiation in the photocatalytic reactor (SB) was measured by o-NB actinometry, based on pH or o-NB concentration. In addition, this work has demonstrated that the o-NB actinometry, followed by o-NB concentration consumption, could be used in the presence of the catalyst TiO2.
En este trabajo se ha estudiado la eficacia de varios Procesos de Oxidación Avanzada (UVC/H2O2, fotocatálisis, Fenton, foto-Fenton, bicarbonato/H2O2 con y sin catalizador) para degradar el fármaco Metoprolol (MET). Además se ha comparado la eficiencia energética de los diferentes procesos y diferentes instalaciones en la eliminación de MET. Los experimentos se realizaron con 50 mg/L iniciales de MET en agua Mili-Q, pH libre y 25ºC. En el caso de la fotólisis, se usaron cuatro instalaciones (solarbox (SB), concentradores parabólicos compuestos (CPC), lámparas black light blue (BLB) y UVC254 nm (UVC)) y el mejor resultado obtenido fue (UVC: 93,5%). Los experimentos UVC se realizaron a diferentes pH y concentraciones de H2O2 con una eliminación de MET de 98%. Los experimentos de fotocatálisis se llevaron a cabo con luz natural y artificial, variando la concentración de TiO2 (0,05, 0,10 y 0,40 g/L). También se realizaron experimentos con 0,4 g/L TiO2 pero variando la concentración inicial del MET (25, 50 y 100 mg/L), el pH, la matriz acuosa y adicionando peróxido de hidrógeno. Los mejores resultados fueron (CPC: 81,5% y SB: 100%). Los experimentos de Fenton se realizaron a pH 3,0 en un reactor de 2 L. Para mejorar el proceso, la adición del Fe (II) se dividió en 5 adiciones realizadas a intervalos constantes de tiempo durante 60 minutos. La mejor degradación de MET fue 87%. Los experimentos de foto-Fenton se realizaron a pH 3,0 y temperaturas de 14ºC y 25ºC en cuatro instalaciones diferentes (BLB, SB, CPC y UVC). Los mejores resultados obtenidos para la eliminación de MET fueron (BLB: 100%; SB: 97,3% y CPC: 98,3%). Los experimentos con bicarbonato/H2O2 se realizaron con 5 mg/L iniciales de MET en agua potable, pH libre y temperatura ambiental en un reactor de 0,5 L. Adicionalmente se utilizó Co (II) y Fe (II) como catalizadores. Eliminación de MET de 100%. Se realizó la identificación de los diferentes intermedios y se han establecido los posibles caminos de degradación del MET. Finalmente se realizó un estudio de un método actinométrico para poder realizar mediciones de radiación en un reactor fotocatalítico en presencia de un catalizador en suspensión.
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38

Philippe, Karine K. "The role of advanced oxidation processes in drinking water treatment." Thesis, Cranfield University, 2010. http://dspace.lib.cranfield.ac.uk/handle/1826/6782.

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Removal of natural organic matter (NOM) is an ever growing challenge for water utilities as many surface waters used for drinking water in the UK exhibit increasing organics levels and it is well known that these organics can lead to problems such as water colouration, unpleasant odour and taste, bacterial growth and disinfection by-products (DBPs) formation. NOM is traditionally removed by coagulation, however in the case of hydrophilic organic matter rich waters the performances of these processes are not able to remove sufficient organic matter leading to potential failures of DBP regulations. Here two advanced oxidation processes (AOPs) UV/H2O2 and TiO2 photocatalytic oxidation were studied to investigate how they could be integrated in a drinking water flowsheet to meet this challenge. Substantial structural changes in the organic matter were observed: loss of aromaticity and double bonded character, shift towards lower molecular weight (MW) more hydrophilic compounds and formation of oxygenated by-products. Although hydrophobic rich waters seem more suitable to AOP treatment as preferential attack of high MW hydrophobic compounds was demonstrated, no correlation was found between physical properties of nine NOM surrogates and removal by UV/TiO2. Dark adsorption onto TiO2 was shown to remove preferentially high molecular weight hydrophobic anionic compound such as tannic acid. UV/H2O2 combined with coagulation did not show any significant benefits in NOM removal as UV/H2O2 appeared to target similar components as coagulation (high MW, hydrophobic and charged) and to form by-products recalcitrant to coagulation. The combination of both AOPs with fresh GAC showed moderate benefits in Abstract ii trihalomethane formation potential (THMFP) and non purgeable organic carbon (NPOC) removal highlighting the role of size and surface chemistry on adsorption onto GAC. Biodegradability of the water did not exhibit any significant change after both AOP treatments within the studied conditions possibly due to insufficient UV irradiation and presence of organics recalcitrant to biodegradation.
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39

Law, Cheuk Fung Japhet. "Catalytic advanced oxidation processes for degradation of environmental emerging contaminants." HKBU Institutional Repository, 2019. https://repository.hkbu.edu.hk/etd_oa/610.

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In recent years, the increasing release of trace organic chemicals to the aquatic environment have been problematic to both the ecosystem and the human society. These trace organic chemicals, regarded as emerging contaminants, include different categories of chemicals, which are either deemed to be safe for human consumption or they are naturally occurring compounds. As a newly recognized class of emerging contaminant, artificial sweeteners are proven to be one of the most ubiquitous classes of emerging contaminants in environmental waters. Its transformation to different suite of TPs during water treatment processes generated more toxic influence than the parent compound is problematic. The realization of the widespread of emerging contaminants, together with their ambiguous fate and impact to the environment have led to the development of advanced oxidation processes that can effectively attenuate this wide range of contaminants. In this work, several catalytic advanced oxidation processes were studied. On one hand, it aimed to evaluate their effectiveness on the removal of the artificial sweetener - acesulfame; and on the other hand, to shed lights on the future development of catalytic advanced oxidation processes. In the first part of this thesis, the photo-Fenton treatment was evaluated on its potential to effectively remove acesulfame together with the produced transformation products, and the post-treatment toxicity screening. The photo-Fenton treatment was found to be effective in removing both the parent compound and the transformation products, without leading to an increase in toxicity, which is largely related to the effective removal of the transformation products. In attempt to reduce the reliance on UV irradiation, newly synthesized carbon and nitrogen co-doped TiO2-based photocatalyst was applied to capture the simulated sunlight for the degradation of acesulfame. The heterogenous photocatalytic treatment was found to involve several different oxidative reactive species for both degradation and transformation by using several scavengers to alter the degradation profile. Unexpected transformation product was also formed upon treatment in actual water matrix, suggesting the impact of water constituents to the transformation of emerging contaminants. Toxicity results indicated the inability to achieve detoxification, suggesting that a more effective degradation process was needed. To accelerate the degradation process, and enhance the performance at neutral pH, the use of redox mediators for Fenton/Fenton-like system was evaluated. Developed novel Fenton-like system involving copper(II) as transition metal ion, persulfate as oxidant and mercaptosuccinic acid as redox mediator led to effective removal of different contaminants. Elucidation of the proposed oxidation mechanism suggested the role of each components of the system, and the generation of different reactive species for degradation as indicated by the different acesulfame transformation profile obtained. The implementation of redox mediators to Fenton/Fenton-like system was beneficial and an effective approach. In short, this work presents several kinds of catalytic advanced oxidation process and shed lights on improving the degradation performance with directions for the future development of better and more effective water treatment processes.
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40

Tummolo, Mauro. "Advanced Oxidation Processes for water remediation by crude oil pollution." Lyon 1, 2009. http://www.theses.fr/2009LYO10005.

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Petroleum or crude oil is a naturally occurring, flammable liquid found in rock formations in the Earth consisting of a complex mixture of hydrocarbons of various molecular weights, plus other organic compounds. Crude oil varies dramatically in colour, odour, composition and flow properties that reflects the diversity of its origin. Crude oil is arguably the world’s most compositionally complex organic mixture, in terms of the number of chemically distinct constituents and is composed of unsaturated and saturated hydrocarbons, heteroatoms (such as N, S, and O). Contamination of soils and water by crude oil and other related products has become a worldwide problem. Petroleum hydrocarbons come into the environment through accidents, spills or leaks, from industrial releases, or as byproducts from commercial or domestic uses. The greatest problem is due to accidental spillage. In the accidental pollution, the diffusion of the petroleum interests the surface of the soil and groundwater. Petroleum hydrocarbons could go into water and soil by geochemical circulation, bringing secondary pollution, even intrude human through food chain. Since crude oil lies over the surface of water and soil, it suffers solar irradiation. Solar degradation is one of the natural ways for petroleum decontamination suggesting techniques based on light irradiation could be useful in the petroleum degradation processes. Light irradiation based technologies have been enhanced by using catalysts, the most effective and cheapest one in water purification being titanium dioxide (TiO2). In the last year, the combined use of ultrasonic irradiation (sonolysis) and photocatalysis to degrade organic pollutants in water (e. G. , effluent of dye works) has been investigated, but no works were found in literature about oil polluted water remediation by using sonophotocatalysis. For this reason, the aim of this thesis work is to investigate on the possibility of oil polluted water remediation using Advanced Oxidation Processes (AOPs). A suspension petroleum/water was prepared in a Pyrex flask (10 L). The flask was filled with 7. 0 L of distilled water, petroleum was added at the ratio 1/20 (oil/water) and the solution was magnetically stirred and then kept in the dark at room temperature to reach equilibrium up to 30 days. The degradation of crude oil dissolved in water was investigated employing either sonolysis at 20 kHz, or photocatalysis on TiO2, or simultaneous sonolysis and photocatalysis (i. E. Sonophotocatalysis), as degradation techniques. For photocatalytic degradation, we used a 125W high‐pressure mercury lamp (Philips, HPK), which provides a maximum energy at 365 nm with an emission range from 200 to 600 nm, and paper supported titanium dioxide as a catalyst. Sonication was carried out by using an ultrasound emitter with an electric power adjustable between 7 and 100 W. Crude oil and water soluble fraction samples were analyzed by using gas‐chromatography mass‐spectrometry (GC‐MS), liquid state nuclear magnetic resonance (1H NMR), Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR‐MS), and fluorescence. The study of non polar compounds in irradiated crude oil by GC‐MS showed an intensification in relative amount of the C13‐C23 fractions and a reduction in relative amount of the C7‐C12 fractions. By use of FT‐ICR‐MS we can see that the irradiation of crude oil produces an oxidation of oil with a particular effect of double bonds oxygenation. Non polar compounds present in crude oil water soluble fraction detected by GC‐MS show a strong presence of branched alkanes and a good amount of linear and aromatic alkanes. All degradation methods utilized have generated an augmentation of C5 class and a decrease of C6‐C9 classes of compounds. In analysis of polar molecules, we can see that total oxygenated compounds were subjected to a small decrease after photocatalysis and a sharp decrease after sonophotocatalytic degradation; no modifications were showed in sonolysis. In FT‐ICR analysis an augmentation of compounds with low molecular weight was also found together with a light increase of number of oxygen atoms in the oxygenated species, as shown in Kendrick and van Krevelen diagrams. In conclusion, we can affirm that ultrasound affects the rate of the photocatalytic degradation of the organic pollutant; the simultaneous use of ultrasound and photocatalysis increased the efficiencies of the degradation process, and a synergistic effect between sonolysis and photocatalysis is normally observed
Le pétrole, probablement le mélange organique le plus complexe, est un liquide naturel et inflammable constitué de composés organiques ayant des propriétés chimiques différentes: hydrocarbures saturés et insaturés, composés hétéro‐atomiques (N S et O) et une petite quantité de métaux. La pollution de l’eau et du sol causée par le pétrole est un problème mondial. Les hydrocarbures arrivent dans l'environnement par des épanchements accidentels ou des fuites industrielles ou, encore, comme sous‐produits de l’activité commercial et domestique. Quelque soit le type de pollution (primaire ou secondaire, c'est‐à‐dire directe ou occasionnel) les hydrocarbures du pétrole arrivent sur la surface du sol et dans l’eau et peuvent arriver dans les nappes aquifères et entrer dans la chaîne alimentaire. L’irradiation solaire représente un procédé naturel d’atténuation des polluants organiques à la surface des sols pouvant servir par exemple à la décontamination de sites contaminés par le pétrole. Ce procès peut être accéléré avec l’utilisation de catalyseurs (photocatalyse) tel que le bioxyde de titane (TiO2) qui semble être le catalyseur le plus efficace et économique. Depuis quelques années on étudie, aussi, l’application soit des ultrasons (sonolyse) soit le couplage sonolyse‐photocatalyse afin de dégrader les polluants organiques dans l’eau. Toutefois la littérature ne reporte pas des articles scientifiques qui appliquent ce couplage pour la purification de l'eau contaminée par les hydrocarbures dérivés du pétrole. Le but de ce travail, pourtant, a été d’étudier la possibilité d'appliquer des méthodes d’oxydation extrême (AOPs, Advanced Oxidation Processes) pour la purification d'eau polluée par le pétrole. Pour les essais de dégradation on a préparé une suspension eau/pétrole dans un récipient en Pyrex (10 L). Dans le récipient on a introduits 7,0 L d'eau distillé et pétrole en rapport 1/20 (pétrole/eau). La solution a été maintenue en agitation à l’obscurité pour 30 jours pour permettre à l'eau de se saturer d’hydrocarbures. La dégradation du pétrole dissous dans l’eau a été menée par sonolyse à 20 kHz, par photocatalyse et par sonophotocatalyse. La dégradation photocatalytique à été menée en utilisant une lampe HPK 125 W et TiO2 comme catalyseur alors que pour la sonolyse on à utilisé un ultrason de puissance électrique enregistrable entre 7 e 100 W. Les échantillons du pétrole ont été analysés par chromatographie gazeuse couplée à la spectrométrie de masse (GC‐MS), par résonance magnétique nucléaire sur le proton liquide (1H RMN), par spectrométrie de masse à Résonance Cyclotronique Ionique et Transformée de Fourier (FT‐ICR‐MS) et par fluorescence. L’étude en GC‐MS des composés non polaires du pétrole irradiés dans le simulateur solaire, a montré, après l’irradiation, une augmentation de la quantité relative de la fraction C13‐C23 et une réduction de la fraction C7‐C12. L’analyse des mêmes échantillons en FT‐ICR‐MS à montré l'oxygénation des doubles liaisons et une augmentation des produits d’oxydation. Les analyses en GC‐MS des composes non polaires, présents dans la fraction soluble du pétrole naturel, ont montrés une forte présence d'alcanes complexes et une grande quantité d'alcanes linéaires et aromatiques. En général, les trois méthodes de dégradation utilisées (sonolyse, photocatalyse, et sonophotocatalyse) ont produit une augmentation des composée en C5 et une diminution de la fraction C6‐C9. Les analyses en FT‐ICR des composés polaires ont relevé rien de remarquable après la sonolyse, une légère diminution des composes oxygénés après les photocatalyse et une évidente réduction des mêmes composes après la sono‐photocatalyse. Les diagrammes de Kendrick et van Krevelen confirment ces résultats: on observe, en effet, une augmentation des composés avec bas poids moléculaire et une légère augmentation d'atomes d’oxygène. En conclusion on peut affirmer que les ultrasons ont une influence remarquable sur la dégradation photocatalytique des polluants organiques. La sonophotocatalyse, pourtant, grâce à la synergie d’action, augmente l'efficacité du procès de dégradation
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41

Brienza, Monica. "Solar Advanced Oxidation Processes for removing emerging contaminants in wasterwater." Thesis, Perpignan, 2015. http://www.theses.fr/2015PERP0001.

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Les usines de traitement des eaux usées ne sont pas prévues pour traiter les polluants émergeants, substances organiques, tels des résidus de médicament, des produits phytosanitaires ou des hormones. Par conséquent, elles sont la source principale d’émission de micropolluants récalcitrants dans l’environnement. La Directive DCE 2000/60/CE demande un "bon statu chimique et biologique” de tous les plans d'eau d'ici 2015. L’objectif principal de cette thèse de doctorat a été d’adopter une méthode respectueuse de l’environnement pour traiter ces polluants. La méthode choisie est basée sur le processus d’oxydation avancée (POA). Elle se base sur la génération par voie solaire, et in situ, d’espèces radicalisées hautement réactives (HO● et/ou SO4-), en se focalisant sur la photocatalyse hétérogène et homogène. Les performances de l'POA ont été évaluées en comparant les taux de dégradation et/ou reminéralisassions des micropolluants. Ce critère a été complété par l'identification des sous-produits, de ses transformations associés et de mesures de toxicité. A cet effet, des tests standards d'écotoxicité ainsi que d'activité oestrogénique ont été réalisés, par la méthode toxicologique ISO ou par le test spécifique inhérent au contrôle de l’activité oestrogénique des eaux usées. Les technologies basées sur les processus d’oxydation avancée par voie solaire peuvent être des méthodes prometteuses de traitement des eaux usées. Toutes les molécules testées sont systématiquement dégradées, même celles présentes à de basses concentrations. La compatibilité environnementale a systématiquement été améliorée. L’irrigation des cultures en réutilisant des eaux usées devient possible
Wastewater effluents are the major source of micropollutants in the environment. These recalcitrant compounds that can be escape from wastewater treatment plant (WWTP) are called emerging contaminants. It is necessary to improve the efficiency of wastewater treatment plants. In fact, Water Framework Directive required a “good chemical and biological status” of all water bodies until 2015. The major aim of the dissertation was to contribute to improve the evaluation of solar advanced oxidation processes, and more specifically heterogeneous and homogeneous photocatalysis, for removing emerging contaminants from wastewater effluents. In this objective, the efficiency of AOPS was not only evaluated with the degradation and/or mineralization rates of the micropollutants. This necessary criterion was completed with the identification of the by-products and the associated transformation pathways, but also with toxicity measurements. This last point was explored with standard ecotoxicity tests and also estrogenic activity that represent a specific test relevant to characterize an identified risk associated to the discharge of effluents into the environment.All the experimental results obtained during this dissertation tends to demonstrate that solar advanced oxidation processes has the potential to open new feasible remediation strategies for WWTPs effluent tertiary treatment before wastewater reuse in irrigation for instance. All the tested molecules have systematically been degraded, high number of micro-organic pollutants initially presented in a mixture were removed even at very low concentration, environmental compatibility is systematically improved
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42

Hantoosh, Mohammed, and Mohammed Hantoosh. "Advanced Oxidation Processes of Trace Organics in Water by Solar Photolysis." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/620873.

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Wastewater reuse is considered globally as a very important element of sustainable water management. Conventional wastewater treatment methods are not effective for the degradation of toxic trace organic compounds, so advanced treatment processes are sometimes needed when the wastewater effluent is likely to be reused or discharged to a river. The existence of toxic trace organic contaminants in the effluent wastewaters has increased awareness of environmental effects and potential concerns for human health. In this work, the advanced oxidation process (AOP) under solar irradiation was successfully used to decompose p-cresol, which is considered to be a toxic trace organic contaminant, from wastewater effluents. The objective of this thesis was to investigate the effect of the EfOM on the overall degradation of the trace organic matter and bulk organic matter through the formation of reactive oxygen species (ROS) and photoexcited dissolved organic matter intermediates (DOM*) under sunlight irradiation. Solar photolysis experiments were conducted to determine the degradation of p-cresol at different conditions, including varying the secondary effluent WW concentration, the initial concentration of the target compound and light intensity. Results from these experiments were reported and discussed to get the optimal treatment processes.
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43

Sanly, Chemical Sciences &amp Engineering Faculty of Engineering UNSW. "Applications of advanced oxidation processes for the treatment of natural organic matter." Publisher:University of New South Wales. Chemical Sciences & Engineering, 2009. http://handle.unsw.edu.au/1959.4/43624.

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Natural organic matter (NOM) occurs ubiquitously in drinking water supplies and is problematic since it serves as a precursor to disinfection by-products (DBPs) formation. Stricter DBP regulations will drive utilities to consider advanced treatment processes for DBP control through NOM removal. Herein, the transformation of NOM in homogeneous (UVA/H2O2 and UVA/Fe/H2O2) and heterogeneous (UVA/TiO2) Advanced Oxidation Processes (AOPs) were studied. Organic matter from three different sources was investigated in this work, specifically a commercial humic acid, and two Australian surface water sources. The transformation of the organic matter as a result of oxidation was investigated through multiple analytical techniques, such as UV-Vis spectroscopy, DOC analysis, high performance size exclusion chromatography (HPSEC), resin fractionation, liquid chromatography with organic carbon detection (LC-OCD) and disinfection byproducts formation potential. The multi-analysis approach is required due to the complex and heterogeneous nature of NOM. Each analytical technique provides complementary information on different properties of NOM, leading to a comprehensive understanding on how AOPs transform the chemical and physical properties of NOM. Both homogeneous and heterogeneous AOPs were found to be effective for NOM removal. However, complete mineralisation was not achieved, even under prolonged irradiation. Large aromatic and hydrophobic organics were degraded into lower molecular weight hydrophilic compounds, which had weak UV absorbance at 254 nm. In the UVA/TiO2 treatment, multi-wavelength HPSEC analysis demonstrated the formation of low molecular weight compounds with strong absorbance at wavelength lower than 230 nm. These residual organic compounds, though recalcitrant, had a low reactivity to chlorine to form THMs, and were identified to be low molecular weight acids and neutral compounds from LC-OCD analysis. Finally, the current work reports the novel synthesis of magnetic photocatalyst for NOM oxidation from low cost precursors to solve the separation problem of nano-sized particles. Magnetite particles were coated with a layer of protective silica from sodium silicate precursor. Photoactive titanium dioxide was then deposited onto the silica coated particles using titanium tetrachloride precursor. The as-prepared magnetic photocatalyst exhibited excellent stability and durability. Although the photoactivity of the magnetic photocatalyst is lower than commercial TiO2 photocatalyst, it can be easily recovered by magnetic field.
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44

Zhang, Tianqi, and Tianqi Zhang. "Modeling Photolytic Advanced Oxidation Processes for the Removal of Trace Organic Contaminants." Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/625878.

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Advanced oxidation processes (AOPs) are commonly used for the destruction of persistent trace organic contaminants (TOrCs) that survive conventional wastewater treatment processes. Three types of AOPs, UV/H2O2, sunlight photolysis and photo-Fenton are experimentally investigated and mathematically quantified to anticipate the fate of TOrCs during oxidation processes, specifically addressing the significant effect of reaction by-products and water matrix on oxidation efficiencies. Hydrogen peroxide UV photolysis is among the most widely used AOPs for the destruction of TOrCs in waters destined for reuse. Previous kinetic models of UV/H2O2 focus on the dynamics of hydroxyl radical production and consumption, as well as the reaction of the target organic with hydroxyl radicals. In this work, we build a predictive kinetic model for the destruction of p-cresol by hydrogen peroxide photolysis based on a complete reaction mechanism that includes reactions of intermediates with hydroxyl radicals. The results show that development of a predictive kinetic model to evaluate process performance requires consideration of the complete reaction mechanism, including reactions of intermediates with hydroxyl radicals. Applying the model to an annular flow-through reactor with reflecting walls, the model mathematically demonstrates that the wall reflectivity significantly enhances the rate of conversion of the target, accounting for the UV light reflection from the reacting walls, as well as the hydrodynamics of the annular flow. Direct and indirect sunlight photolysis is critically important in the breakdown of contaminants in effluent wastewater. The fate of a suite of TOrCs and estrogenic activity were investigated in an effluent-dependent stream. Some TOrCs, which are not sufficiently attenuated through biodegradation and soil adsorption were destructed obviously with distance of travel in the stream. Independent experiments, conducted in batch reactor with 17α-ethinylestradiol (EE2) spiked in effluent showed that attenuation of estrogenic compounds maybe due in part to indirect photolysis caused by formation of reactive species from sunlight absorption. Further investigation was conducted using selective probe compounds to characterize reactive species. And results showed that singlet oxygen generated from excited state of effluent organic matter was responsible for essentially all observed transformations of targets in the effluent in Tucson. To mathematically quantify the photo-Fenton AOP, a kinetic model is proposed for the photolysis of Fe3+ hydroxo complexes at low pH (pH ≤ 3.0). The model incorporates elementary reactions of the Fenton-like and UV/H2O2 system. Iron speciation and photochemical parameters, including the molar absorptivities of light-absorbing species and the quantum yields of Fe3+ and FeOH2+ hydrolysis are experimentally validated. However, the predicted, time-dependent Fe2+ concentrations during Fe3+ photolysis are much lower than measured. The possible missing elements in the model could be (i) quenching of OH radicals by unknown species, or/and (ii) shielding of Fe2+ by unknown compounds at the beginning of the process.
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45

Bernat, Camí Xavier. "Treatment of biorefractory wastewater through membrane-assisted oxidation processes." Doctoral thesis, Universitat Rovira i Virgili, 2010. http://hdl.handle.net/10803/8583.

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La escasez de agua se presenta como uno de los mayores retos para asegurar el desarrollo sostenible. Entre otras actuaciones, se deben investigar e implementar sistemas eficientes de tratamiento de aguas biorecalcitrantes, que necesitan ser condicionadas antes de su depuración biológica. Uno de los posibles pre-tratamientos es el proceso Fenton de oxidación avanzada, que presenta dos principales inconvenientes: la utilización de sales de hierro como catalizador homogéneo, que abandonan continuamente la etapa de oxidación, y el elevado consumo de oxidante, en parte desaprovechado. La presente tesis se centra en el estudio de la mejora del proceso Fenton de aguas fenólicas mediante su acoplamiento con tecnologías de membrana como la nanofiltración, la emulsificación con membranas o los reactores de membrana. El acoplamiento de dichas tecnologías con el proceso Fenton permite el confinamiento del catalizador y el aumento de la eficiencia de oxidación, mejorando así el tratamiento en términos ambientales y económicos.
Water scarcity is one of the major challenges for assuring a sustainable development. Among other measures, research into efficient wastewater treatment systems to deal with biorefractory wastewaters, which need to be amended before their biological degradation, is required. The Fenton process is an advanced oxidation process that can be used as potential pre-treatment for this purpose. However, the pre-treatment presents two main limitations: the use of iron salts as homogeneous catalyst, which are continuously thrown away in the reactor effluent, and the high consumption of oxidant, which is partially wasted. The present thesis aims at studying the improvement of the Fenton process applied on phenolic wastewater through its coupling with membrane technologies such as nanofiltration, membrane emulsification or membrane reactors. The coupling allows confining the catalyst and increasing the oxidation efficiency, thus enhancing the treatment efficiency in environmental and economic terms.
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46

Gutmann, Emanuel. "Nasschemisch synthetisierte, oxidische Nanomaterialien mit pyroelektrokatalytischen und photokatalytischen Eigenschaften für Anwendungen in der Desinfektionstechnologie." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2013. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-102099.

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Im Rahmen der vorliegenden Arbeit wurden zwei verschiedene Klassen oxidischer Nanomaterialien nasschemisch synthetisiert und strukturell-morphologisch charakterisiert. Zum einen betrifft dies TiO2-, TiO2/SiO2-, Ag/TiO2- und Pd/TiO2-Sole, welche die photokatalytisch aktive Modifikation Anatas in nanokristalliner Form enthalten und über einen solvothermalen Sol-Gel-Prozess hergestellt werden konnten. Im Hinblick auf eine potentielle Anwendung in der Desinfektionstechnologie und für den Abbau organischer Umweltschadstoffe wurde die photokatalytische Aktivität von Pulvern und Beschichtungen auf Textil durch E. coli-Abtötung bzw. Modellfarbstoffabbau untersucht. Im Weiteren wurde die antimikrobielle Aktivität pyroelektrischer LiNbO3- und LiTaO3-Pulvermaterialien unter zyklischer thermischer Anregung nachgewiesen. Diese als Pyroelektrokatalyse bezeichnete Nutzung des pyroelektrischen Effektes in einem katalytischen bzw. elektrochemischen Prozess ist dabei von grundlegender Neuheit. Aufsetzend auf den physiko-chemischen Grundlagen dieses Phänomens wurde eine Hypothese des Mechanismus entwickelt und in Analogie zur Photokatalyse diskutiert
This thesis deals with two classes of oxidic nanomaterials that were synthesized by chemical solution routes and characterized with respect to structure and morphology. Sols of TiO2, TiO2/SiO2, Ag/TiO2 and Pd/TiO2 containing the photocatalytically active modification anatase in nanocrystalline form were prepared via a solvothermal sol-gel process. With regard to potential application in disinfection and environmental remediation technology the photocatalytic activity of powders and coatings on textile was investigated by means of E. coli decomposition and organic dye degradation. Further the antimicrobial activity of pyroelectric LiNbO3 and LiTaO3 powder materials under cyclical thermal excitation was demonstrated. In this context the application of the pyroelectric effect in a catalytic or electrochemical process – termed as pyroelectrocatalysis – is of fundamental novelty. Based on the physico-chemical principles of the phenomenon a hypothesis of the mechanism was developed and discussed in analogy with photocatalysis
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47

Paiva, Frederico José de Vaz e. "Redução de carga orgânica recalcitrante de efluente de indústria gráfica por reação de fenton." Universidade do Estado do Rio de Janeiro, 2009. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=2960.

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A Casa da Moeda do Brasil (CMB) é uma empresa nacional, com mais de 300 anos de experiência na produção de valores e impressos de segurança. A produção de cédulas, realizada pelo Departamento de Cédulas (DECED), consiste de três etapas de impressão, off-set, calografia e tipografia, seguida de acabamento e embalagem semi-automatizado. A impressão calcográfica consome solução de limpeza, composta de soda cáustica e óleo sulfonado, para limpeza do cilindro de impressão, gerando um efluente líquido saturado de tinta. Este efluente apresenta baixa biodegradabilidade, apresentando uma relação DBO / DQO de aproximadamente 1:4. Em termos de tratabilidade, as estações de tratamento de efluentes (ETE) apresentam uma configuração convencional, por via biológica, demonstram pouca eficiência na degradação da matéria orgânica deste efluente. Com compostos recalcitrantes, torna-se necessária a inclusão de uma etapa terciária que permita sua degradação por via química, permitindo o descarte do efluente com características menos danosas ao ambiente. Neste trabalho, aplicou-se a reação de Fenton no efluente do DECED por sua capacidade de converter a matéria orgânica em gás carbônico e água ou, caso seja utilizado em pré-tratamentos, torna-os biodegradáveis. Foram estudadas diferentes condições para medir a influência de diferentes parâmetros na eficiência da reação. A reação de Fenton consiste na geração de radicais hidroxil (HO), por diferentes rotas, em quantidades suficientes para a degradação de matéria orgânica. Esses radicais são gerados a partir de peróxido de hidrogênio (H2O2) em reações com diferentes precursores como ozônio (O3), luz UV (ultravioleta), ultra-som e sais de ferro. No presente trabalho restringiu-se às reações com sais de ferro. Dentre os resultados obtidos, verificou-se o tempo mínimo para reação em 10 minutos. A relação entre íons ferro e peróxido de hidrogênio é menor do que a literatura normalmente sugere, 1:2, contra 1:3. Como a solução de sulfato ferroso é muito instável, passando os íons ferrosos a férricos, utilizou-se a adição direta do sal. Em escala industrial, a solução de sulfato ferroso deve ser preparada em poucas quantidades para que tenha baixo tempo de estocagem, a fim de não ser degradada. A temperatura, na faixa estudada (de 20C à 45C), é um parâmetro que tem pouca influência, pois a redução da eficiência da reação foi pequena (de 99,0% para 94,9%). O ferro utilizado na reação não se demonstrou uma nova fonte de transtornos para o ambiente. Nas condições utilizadas, a concentração de ferro residual esteve próxima ao limite permitido pela legislação no efluente tratado, necessitando apenas de alguns ajustes para a correção do problema
The Brazilians Mint (CMB) is a national enterprise, with more than 300 years of experience in the production of values and security printings. The production of banknotes, carried out by the Departamento de Cédulas (DECED), consists of three printing stages: off-set, intaglio and typography, followed by finishing and semiautomated packing. The intaglio impression consumes cleaning solution, composed by caustic soda and sulfonated castor oil, for cleaning of the printing cylinder, producing an ink saturated wastewater. This wastewater presents low biodegradability, showing a BOD / COD ratio of approximately 1:4. In terms of treatability, the effluent treatment stations (ETS) has presented a conventional configuration, for biological means, has showed a low efficiency in the organic matter degradation of this effluent. With recalcitrant compounds, its necessary the inclusion of a tertiary stage that allows its degradation by chemical means, allowing discarding it with less harmful characteristics to the environment. In this work, the Fenton reaction was applied in the DECED industrial wastewater due to its capacity of converting the organic matter into carbonic gas and water or, if it is used in pay-treatment, turn them into biodegradable (AGUIAR et al., 2007). Different conditions have been studied to measure the influence of different parameters in the reaction efficiency. The Fenton reaction consists in the hidroxyl radicals (HO) generation, by different means, in sufficient quantities for the organic matter degradation. These radicals are produced from of peroxide hydrogen (H2O2) in reactions with different precursors like ozone (O3), UV light, ultrasound and iron salts (GOGATE and PANDIT, 2004). Here we restricted ourselves to the reactions with iron salts. Among the obtained results, it has been verified the minimun time for reaction in 10 minutes. The ratio between iron ions and hydrogen peroxide is lower than suggests the literature (1:2), against (1:3). Since the ferrous sulphate solution is very unstable, because the ferrous ions turn into ferric ions, straight addition of the salt was used. In industrial scale, the ferrous sulfate solution must be prepared in little quantities so that it has low time of stock, in order to not be degraded. The temperature, in the studied range, is a parameter that has little influence, since the efficiency reduction of the reaction was low. The iron used in the reaction did not demonstrate itself a new source of damages for the environment. In the used conditions, the iron concentration was near to maximum limit allowed by the legislation in the effluent treatment, just needing some adjustments to sort out the problem
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48

Santana, Caroline Martins. "Estudo da degradação de corante têxtil em matrizes aquosas por meio dos processos oxidativos avançados O3-H2O2/UV e foto-Fenton." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-11082010-143735/.

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A indústria têxtil gera grandes volumes de efluentes com elevada carga orgânica, forte coloração e toxicidade. Neste trabalho, estuda-se o tratamento de solução aquosa contendo o corante Solophenyl Yellow Arle 154% por meio dos processos O3-H2O2/UV e foto-Fenton, avaliando-se as repostas: remoção de cor em 5 minutos, remoção de cor em 60 minutos, taxa máxima de remoção de cor e remoção de COT em 60 minutos. Os experimentos foram realizados em semibatelada com circulação usando um reator fotoquímico com campo de radiação anular coaxial, constituído de corpo cilíndrico em aço com refletor interno de alumínio para 12 lâmpadas fixadas simetricamente na superfície refletora e um tubo reator em quartzo de 0,7 L, posicionados verticalmente no eixo do refletor. Para o processo O3-H2O2/UV foram utilizadas lâmpadas Phillips TUV (36 W, 254 nm). A corrente gasosa contendo O3 foi introduzida no reator por meio de um difusor. Para o processo foto-Fenton foram utilizadas lâmpadas Sylvania (12 W cada, 300 400 nm) e concentração de Fe(II) de 0,25 mmol/L. Em ambos os processos, solução de peróxido de hidrogênio foi adicionada durante os 30 minutos iniciais de tratamento. As amostras foram analisadas por medidas de carbono orgânico total (COT) e remoção de cor (absorbância medida em 405 nm em espectrofotômetro UV-visível). Em ambos os processos utilizou-se o planejamento experimental Doehlert, definindo os valores mínimo e máximo para cada variável adotada. No caso do processo O3- H2O2/UV (ETAPA I), foram estudados os efeitos da potência elétrica total das lâmpadas (144 432 W), concentração de H2O2 (5 30 mmol/L), concentração inicial de corante (20 100 mg/L), concentração de ozônio (10 40 mg/L) e pH (3 10). No processo foto-Fenton (ETAPA II), estudaram-se os efeitos da potência (160 480 W), concentração de H2O2 (5 30 mmol/L) e concentração inicial de corante (20 100 mg/L). Os resultados da ETAPA I indicaram que o aumento da concentração do corante, em meio ácido, aumenta a remoção de cor em 5 e 60 minutos, sugerindo a eficiência da ação via ozônio molecular sob o grupo cromóforo do corante. Os melhores resultados apresentaram remoção acima de 95% em 5 e 60 minutos de tratamento. Entretanto, para a remoção de COT em 60 minutos o processo não foi eficiente, apresentando resultado máximo de 35,6%. Na ETAPA II obtiveram-se resultados menos satisfatórios para remoção de cor se comparados aos da ETAPA I (56,1% em 5 minutos e 78% em 60 minutos de tratamento), mas melhores em relação à remoção de COT em 60 minutos atigindo 45,1% de remoção. As maiores taxas de remoção de cor foram observadas nos 5 primeiros minutos de tratamento para todos os experimentos. Experimentos complementares realizados em uma terceira etapa (ETAPA III) mostraram que a aplicação do processo O3 seguido do processo foto-Fenton permitiu resultados satisfatórios tanto para remoção de cor (97,2%), quanto para remoção de COT (69,5%). O estudo da ação do processo O3 em modo contínuo e a avaliação econômica preliminar do processo integrado O3 - foto-Fenton sugerem o potencial de aplicação do tratamento integrado a indústrias têxteis.
The textile industry generates large volumes of wastewater with high organic load, strong coloration and toxicity. In this work, the treatment of an aqueous solution containing the dye Solophenyl Yellow Arle 154% was studied by the O3-H2O2/UV and photo-Fenton processes, in order to evaluate the responses color removal after 5 minutes; color removal after 60 minutes; maximum rate of color removal; and TOC removal after 60 minutes. The experiments were carried out in the semi-batch mode with circulation using a photochemical reactor with annular coaxial radiation field, consisting of a cylindrical stainless steel support with an aluminum internal reflector with 12 lamps fixed symmetrically in the internal reflecting surface, and a quartz tube reactor of 0.7 L, positioned vertically along the axis of the reflector. For the O3- H2O2/UV process, Phillips TUV lamps (36 W, 254 nm) were used; the gas stream containing zone was introduced into the reactor through a diffuser. For the photo- Fenton process, Sylvania lamps (12 W each, 300 - 400 nm) and a concentration of Fe (II) of 0.25 mmol/L were used. In both cases, the hydrogen peroxide solution was added in the first 30 minutes of treatment. The samples were analyzed by the measurement of total organic carbon (TOC) and color removal (absorbance measured at 405 nm in a UV-visible spectrophotometer). In both cases the Doehlert experimental design was used, defining the minimum and maximum values of each variable adopted. In the case of O3-H2O2/UV process (PHASE I), the effects of the total electric power of the lamps (144 - 432 W), H2O2 concentration (5 - 30 mmol/L), initial dye concentration (20 - 100 mg/L), ozone concentration (10 - 40 mg/L), and pH (3 - 10) were studied. For the photo-Fenton process, the studied variables were: total electric power of the lamps (160 - 480 W), H2O2 concentration (5 - 30 mmol/L), and initial dye concentration (20 - 100 mg/L). The results of PHASE I indicated that the increase of dye concentration in acidic conditions increases color removal after 5 and 60 minutes, thus suggesting the efficiency of molecular ozone action upon the chromophore group of the dye. The best results showed color removal above 95% after 5 and 60 minutes of treatment. However, for the TOC removal the process was not efficient, with maximum removal after 60 minutes of only 35.6%. In PHASE II less satisfactory results for color removal were obtained in comparison with PHASE I (56.1% after 5 minutes and 78% after 60 minutes of treatment), but with higher TOC removal after 60 minutes, achieving over 45.1%. The highest color removal rates were observed within the first 5 minutes of treatment for all runs. Additional experiments carried out in PHASE III showed that the oxidation by O3 followed by the photo-Fenton process enabled to achieve suitable results for both color (97.2%) and TOC removals (69.5%). The study of the O3 process in the continuous mode and a preliminary economic evaluation suggests a high potential for the use of the integrated O3-photo-Fenton process in textile industries.
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49

劉偉藻 and Wai-cho Ivan Lau. "Removal of refractory chemicals in landfill leachate by UASB and advanced oxidation processes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31240471.

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50

Rossouw, Arnoux. "Modified track-etched membranes using photocatalytic semiconductors for advanced oxidation water treatment processes." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80276.

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Thesis (MScEng)--Stellenbosch University, 2013.
ENGLISH ABSTRACT: The purpose of this study was to develop modi ed tract-etched membranes using nanocomposite TiO2 for advanced water treatment processes. Photocatalytic oxidation and reduction reactions take place on TiO2 surfaces under UV light irradiation, therefore sunlight and even normal indoor lighting could be utilised to achieve this effect. In membrane ltration, caking is a major problem, by enhancing the anti-fouling properties of photocatalysts to mineralise organic compounds the membrane life and e ciency can be improved upon. In this study the rst approach in nanocomposite membrane development was to directly modify the surface of polyethylenetherephthalate (PET) track-etched membranes (TMs) with titanium dioxide (TiO2) using inverted cylindrical magnetron sputtering (ICMS) for TiO2 thin lm deposition. The second approach was rst to thermally evaporate silver (Ag) over the entire TM surface, followed by sputtering TiO2 over the silver-coated TM. As a result a noble metal-titania nanocomposite thin lm layer is produced on top of the TM surface with both self-cleaning and superhydrophilic properties. Reactive inverted cylindrical magnetron sputtering is a physical vapour deposition method, where material is separated from a target using high energy ions and then re-assimilated on a substrate to grow thin lms. Argon gas is introduced simultaneously into the deposition chamber along with O2 (the reactive gas) to form TiO2. The photocatalytic activity and other lm properties, such as crystallinity can be in uenced by changing the sputtering power, chamber pressure, target-to-substrate distance, substrate temperature, sputtering gas composition and ow rate. These characteristics make sputtering the perfect tool for the preparation of di erent kinds of TiO2 lms and nanostructures for photocatalysis. In this work, the utilisation of ICMS to prepare photocatalytic TiO2 thin lms deposited on track-etched membranes was studied in detail with emphasis on bandgap reduction and TM surface regeneration. Nanostructured TiO2 photocatalysts were prepared through template directed deposition on track-etched membrane substrates by exploiting the good qualities of ICMS. The TiO2-TM as well as Ag-TiO2-TM thin lms were thoroughly characterised. ICMS prepared TiO2 lms were shown to exhibit good photocatalytic activities. However, the nanocomposite Ag-TiO2 thin lms were identi ed to be a much better choice than TiO2 thin lms on their own. Finally a clear enhancement in the photocatalytic activity was achieved by forming the Ag-TiO2 nanocomposite TMs. This was evident from the band-gap improvement from 3.05 eV of the TiO2 thin lms to the 2.76 eV of the Ag-TiO2 thin lms as well as the superior surface regenerative properties of the Ag-TiO2-TMs.
AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om verbeterde baan-ge etste membrane (BMe) met behulp van nano-saamgestelde titaandioksied (TiO2) vir gevorderde water behandeling prosesse te ontwikkel. Fotokatalitiese oksidasie- en reduksie reaksies vind plaas op die TiO2 oppervlaktes onder UV-lig bestraling, en dus kan sonlig en selfs gewone binnenshuise beligting gebruik word om die gewenste uitwerking te verkry. In membraan ltrasie is die aanpaksel van onsuiwerhede 'n groot probleem, maar die verbetering van die self-reinigende eienskappe van fotokatalisators deur organiese verbindings te mineraliseer, kan die membraan se leeftyd en doeltre endheid verbeter word. In hierdie studie was die eerste benadering om nano-saamgestelde membraan ontwikkeling direk te verander deur die oppervlak van polyethylenetherephthalate (PET) BMe met 'n dun lagie TiO2 te bedek, met behulp van reaktiewe omgekeerde silindriese magnetron verstuiwing (OSMV).Die tweede benadering was eers om silwer (Ag) termies te verdamp oor die hele BM oppervlak, gevolg deur TiO2 verstuiwing bo-oor die silwer bedekte BM. As gevolg hiervan is 'n edelmetaal-titanium nano-saamgestelde dun lm laag gevorm bo-op die oppervlak van die BM, met beide self-reinigende en verhoogde hidro liese eienskappe. OSMV is 'n siese damp neerslag metode, waar materiaal van 'n teiken, met behulp van ho e-energie-ione, geskei word, en dan weer opgeneem word op 'n substraat om dun lms te vorm. Argon gas word gelyktydig in die neerslag kamer, saam met O2 (die reaktiewe gas), vrygestel om TiO2 te vorm. Die fotokatalitiese aktiwiteit en ander lm eienskappe, soos kristalliniteit, kan be nvloed word deur die verandering van byvoorbeeld die verstuiwingskrag, die druk in die reaksiekamer, teiken-tot-substraat afstand, substraattemperatuur, verstuiwing gassamestelling en vloeitempo. Hierdie eienskappe maak verstuiwing die ideale hulpmiddel vir die voorbereiding van die verskillende soorte TiO2 lms en nanostrukture vir fotokatalisasie. In hierdie tesis word OSMV gebruik ter voorbereiding van fotokatalitiese TiO2 dun lms, wat gedeponeer is op BMe. Hierdie lms word dan in diepte bestudeer, met die klem op bandgaping vermindering en BM oppervlak hergenerasie. Nanogestruktureerde TiO2 fotokataliste is voorberei deur middel van sjabloongerigte neerslag op BM substrate deur die ontginning van die goeie eienskappe van OSMV. Die TiO2-BM dun lms, sowel as Ag-TiO2-BM dun lms, is deeglik gekarakteriseer. OSMV voorbereide TiO2 dun lms toon goeie fotokatalitiese aktiwiteite. Nano-saamgestelde Ag-TiO2 dun lms is egter ge denti seer as 'n veel beter keuse as TiO2 dun lms. Ten slotte is 'n duidelike verbetering in die fotokatalitiese aktiwiteit bereik deur die vorming van die Ag-TiO2 nano-saamgestelde BMe. Dit was duidelik uit die bandgapingverbetering van 3,05 eV van TiO2 dun lms in vergelyking met die 2,76 eV van Ag-TiO2 dun lms. 'n Duidelike verbetering is behaal in die fotokatalitiese aktiwiteit deur die vorming van die Ag-TiO2 nano-saamgestelde TMs.
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