Dissertations / Theses: 'Acroleina'

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Liosi, Giuseppe. "Un nuovo processo per la sintesi di acroleina e acido acrilico da glicerolo." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/2562/.

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La trasformazione di glicerolo ad acido acrilico può essere un fattore importante per la valorizzazione del processo di produzione di biodiesel, il quale prevede la coproduzione di enormi quantità di glicerolo. La sintesi di acido acrilico in un unico step è stata studiata attraverso vari catalizzatori solidi bifunzionali di diversa natura, contenenti proprietà acide e redox. I catalizzatori devono avere un’adeguata acidità di Brønsted per promuovere la trasformazione di glicerolo ad acroleina, mentre le proprietà ossidanti, necessarie per la sintesi di acido acrilico sono ottenute mediante l’inserimento di un metallo ossidante nella struttura. Si vuole quindi sintetizzare e testare una serie di catalizzatori che mostrino questa bifunzionalità in grado di soddisfare requisiti di attività e selettività nei confronti della reazioni . Per questo studio sono stati sintetizzati e caratterizzati ossidi misti di W/V, nella forma di aggregati dispersi sulla titania ed ossidi misti di Zr/Nb/V in struttura bulk. Sono stati quindi eseguiti dei test di reattività in fase gas ed in presenza di ossigeno utilizzando un reattore tubolare in quarzo a letto fisso.

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Weinschutz, Regina. "Oxidação parcial do etanol sobre catalisador de Fe-Mo para obtenção de aldeidos e compostos de condensação aldolica." [s.n.], 1999. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266158.

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Orientador: Jose Claudio Moura Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica Made available in DSpace on 2018-07-24T13:10:52Z (GMT). No. of bitstreams: 1 Weinschutz_Regina_D.pdf: 3734853 bytes, checksum: 73f3013ad5ac6c9222df27cd5ad923c7 (MD5) Previous issue date: 1999 Resumo: A reação de oxidação parcial de etanol para a produção de aldeídos e compostos de condensação aldólica, sobre catalisador de Fe/Mo é estudada em um microrreator tubular e leito fixo, com o objetivo de verificar a distribuição de produtos nas condições estudadas, ou seja temperatura de 300 a 360°C, razão molar de 10 a 30 e tempo espacial modificado de 2,5 a '5,4g IND. cm.min'.'(N1) POT. '-1' . A conversão de etanol é total, formando, principalmente, acetaldeído e etileno em quantidades abaixo de 19% nas condições em que o trabalho foi realizado. Devido ao consumo total de etanol o acetaldeído é utilizado como reagente de referência por ser o composto intermediário para a produção de formaldeído, acroleína e outros produtos oxigenados, além do dióxido de carbono. A conversão de acetaldeído cresce com o aumento da temperatura atingindo 97% a 360°C. O consumo de acetaldeído é expresso por um modelo empírico, com ordens 0,5 e 1,0 em relação às pressões parciais de acetaldeído e de oxigênio, respectivamente. A água formada reduz a taxa de consumo do acetaldeído, porém com influência decrescente com o aumento da temperatura. Os parâmetros da equação da taxa de reação foram obtidos, à partir dos dados experimentais, bem como a dependência da taxa em relação a concentração de água no sistema Abstract: The partial oxidation reaction of ethanol for the production of aldehydes and compounds of aldol condensation, over catalyst of Fe-Mo it was studied in a fixed bed tubular microrreator. The reactor was operated in the conditions studied,that is, temperature range at 300 to 360°C, air ethanol molar ratio molar range of 10 to 30 and modified space time range of 2,5 to '5,4g IND. cm.min'.'(N1) POT. '-1'. The ethanol conversion is total, forming acetaldehyde and its secundary reaction products in the conditions in that the work was accomplished. Due to the total consumption of ethanol, the acetaldehyde was used as reference reactant. lt is the intermediary reagent for the productio of formaldehyde, acrolein and other oxygenated products, besides carbon dioxide and water. The acetaldehyde conversion increases with the increasing reactions temperatures, reaching 97% at 360°C. The consumption of acetaldehyde is expressed by an empirical reaction rate, with orders 0,5 and 1,0 in relation to the partial pressures of acetaldehyde and of oxygen, respectively. Water formed during the course of the reaction reduces the rate of consumption of the acetaldehyde, the effect decreases with the increasing temperatures. The Arrhenius parameters of the reaction rate were obtained from the experimental data, as well as the dependence ofthe rate on the concentration ofwater in the system Doutorado Desenvolvimento de Processos Químicos Doutor em Engenharia Química

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Mastragostino, Giada. "Analisi del ciclo di vita della produzione industriale di acroleina: confronto tra il processo tradizionale e vie di sintesi alternative." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/6534/.

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La green chemistry può essere definita come l’applicazione dei principi fondamentali di sviluppo sostenibile, al fine di ridurre al minimo l’impiego o la formazione di sostanze pericolose nella progettazione, produzione e applicazione di prodotti chimici. È in questo contesto che si inserisce la metodologia LCA (Life Cycle Assessment), come strumento di analisi e di valutazione. Il presente lavoro di tesi è stato condotto con l’intenzione di offrire una valutazione degli impatti ambientali associati al settore dei processi chimici di interesse industriale in una prospettiva di ciclo di vita. In particolare, è stato studiato il processo di produzione di acroleina ponendo a confronto due vie di sintesi alternative: la via tradizionale che impiega propilene come materia prima, e l’alternativa da glicerolo ottenuto come sottoprodotto rinnovabile di processi industriali. Il lavoro si articola in due livelli di studio: un primo, parziale, in cui si va ad esaminare esclusivamente il processo di produzione di acroleina, non considerando gli stadi a monte per l’ottenimento delle materie prime di partenza; un secondo, più dettagliato, in cui i confini di sistema vengono ampliati all’intero ciclo produttivo. I risultati sono stati confrontati ed interpretati attraverso tre tipologie di analisi: Valutazione del danno, Analisi di contributo ed Analisi di incertezza. Dal confronto tra i due scenari parziali di produzione di acroleina, emerge come il processo da glicerolo abbia impatti globalmente maggiori rispetto al tradizionale. Tale andamento è ascrivibile ai diversi consumi energetici ed in massa del processo per l’ottenimento dell’acroleina. Successivamente, per avere una visione completa di ciascuno scenario, l’analisi è stata estesa includendo le fasi a monte di produzione delle due materie prime. Da tale confronto emerge come lo scenario più impattante risulta essere quello di produzione di acroleina partendo da glicerolo ottenuto dalla trans-esterificazione di olio di colza. Al contrario, lo scenario che impiega glicerolo prodotto come scarto della lavorazione di sego sembra essere il modello con i maggiori vantaggi ambientali. Con l’obiettivo di individuare le fasi di processo maggiormente incidenti sul carico totale e quindi sulle varie categorie d’impatto intermedie, è stata eseguita un’analisi di contributo suddividendo ciascuno scenario nei sotto-processi che lo compongono. È stata infine eseguita un’analisi di incertezza tramite il metodo Monte Carlo, verificando la riproducibilità dei risultati.

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Puglia, Giuseppe. "Nuovi catalizzatori per la trasformazione diretta di glicerolo ad acido acrilico." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amslaurea.unibo.it/5738/.

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Alla luce delle improrogabili necessità ambientali, le prospettive di crescita del mercato dei bio-combustibili e quindi del biodiesel, sono molto ampie; si rende quindi necessario lo sviluppo di nuovi processi chimici in grado di valorizzare il co-prodotto della sintesi del biodiesel, ovvero il glicerolo. Tra le varie opzioni proposte dalla recente letteratura scientifica e brevettuale, la trasformazione one-pot del glicerolo ad acido acrilico può rappresentare una soluzione. All’interno di questa tematica, durante il periodo di tesi ho eseguito uno studio di catalizzatori a base di ossidi misti contenenti tungsteno, molibdeno e/o vanadio. Tali ossidi presentano sia funzionalità acida, necessaria per il primo stadio di disidratazione del glicerolo ad acroleina, sia funzionalità redox, necessaria all’ossidazione dell’acroleina ad acido acrilico. I sistemi tri-componente W-V-Mo si sono rivelati catalizzatori attivi e selettivi per la sintesi diretta di glicerolo ad acido acrilico. La miglior performance catalitica di questa classe di catalizzatori ha consentito di ottenere selettività in acido acrilico del 31%, con selettività totale ad acido acrilico ed acroleina superiore al 38% (valori tra i più elevati rispetto a quelli riportati in letteratura). Infine, si è dimostrato che i catalizzatori a base di W-V-Mo sono sistemi potenzialmente sfruttabili anche in impianti a doppio stadio per la produzione di acido acrilico con alimentazioni miste propilene/glicerolo. Ulteriori studi sono attualmente in corso per approfondire le capacità catalitiche degli ossidi misti studiati.

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Ynocente, Castillejo Elizabeth. "Calibración del método colorimétrico 4- hexilresorcinol para el análisis de acroleina y su aplicación a los gases de combustión de un motor diesel." Universidad Nacional de Ingeniería. Programa Cybertesis PERÚ, 2004. http://cybertesis.uni.edu.pe/uni/2004/ynocente_ce/html/index-frames.html.

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Cordoba, Aymer Yeferson Maturana. "Estudo da combustão direta da glicerina bruta e loira como alternativa de aproveitamento energético sustentável." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/18/18147/tde-21122011-191948/.

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Nesta tese investiga-se e avalia-se a combustão direta da glicerina bruta e loira, co-produto e derivado, respectivamente, do processo de fabricação do biodiesel como alternativa de aproveitamento energético sustentável. Focaliza-se especialmente nos aspectos ambiental, técnico e econômico considerando as emissões, a transferência de calor associada e os aspectos operacionais como o eixo principal do estudo. Visa aumentar o conhecimento atual a respeito e contribuir para a melhoria das perspectivas da indústria do biodiesel e de uma parte da população. Para a combustão de glicerina bruta proveniente do processo de fabricação de biodiesel de sebo bovino desenvolveu-se um queimador tipo vórtice para glicerina bruta, avaliaram-se e quantificaram-se as emissões de óxidos de enxofre e nitrogênio, monóxido e dióxido de carbono, hidrocarbonetos totais, formaldeído, acetaldeído e acroleína, sendo também avaliados os efeitos mutagênicos potenciais dos gases produzidos. Da mesma forma foi estudada a composição físico-química, poder calorífico, decomposição térmica e a transferência de calor associada, além dos parâmetros operacionais da combustão, entre eles, a relação ar-combustível, temperatura de chama adiabática e o desempenho geral do processo para diferentes coeficientes de excesso de ar. Os ensaios foram desenvolvidos utilizando-se uma fornalha flamo tubular dotada de 12 câmaras calorimétricas e totalmente instrumentada com sensores de temperatura e sondas para análise contínua de gases em analisadores automáticos, fornecimento e controle de água de resfriamento e sistema de captação de dados em tempo real. Adicionalmente aos requisitos do estudo, foi necessário o desenvolvimento de sistemas e equipamentos auxiliares como a unidade de acondicionamento e alimentação de glicerina bruta e métodos de filtragem. Paralelamente, os efeitos mutagênicos e tóxicos foram avaliados sobre o bio-sensor Tradescantia (Clone KU-20), adaptando câmaras de intoxicação e técnicas de análise biológica desenvolvidas previamente. Os resultados foram processados, avaliados e comparados com as emissões e comportamento observado durante a combustão direta do óleo diesel, constatando-se que a combustão direta de glicerina bruta é um processo viável e suas emissões de CO, NOx, \'SO IND.2\' e HCT foram em média 39%, 75%, 69% e 38% respectivamente menores do que as do óleo diesel, porém o material particulado emitido pela glicerina bruta, e ainda mais pela loira, foi várias vezes superior do que com óleo diesel. Do mesmo modo, o nível de acroleína detectado no gás de combustão de glicerina bruta (214 ppbv) aparentemente não representa perigo para a população. Igualmente a energia produzida a partir da glicerina bruta resultou 61% e 58% mais barata do que com óleo diesel e glicerina loira respectivamente em condições semelhantes. No entanto, certamente verificou-se que a combustão de glicerina bruta é um processo tecnicamente mais complexo quando comparado com a dos combustíveis convencionais e evidenciou-se a necessidade de fazer um controle adequado das partículas emitidas para avançar no desenvolvimento do processo. Desta forma o presente estudo constitui-se em uma fonte importante de informação sobre a glicerina bruta e outros combustíveis similares para autoridades ambientais, indústrias e pesquisadores. This thesis investigated and evaluated on the assessment of the direct combustion of crude and technical glycerin, by-product and derivative respectively of Brazilian biodiesel manufacture process, as an alternative of sustainable energy use. The main axis of the study were the environmental, technical and economical aspects, focusing in emissions, heat transfer and the operational parameters associated with the combustion of crude and technical glycerin. It aims to increase the knowledge on the matter and contribute to the improvement of the economic and environmental perspective of biodiesel industry and isolated populations. It was evaluated the combustion of crude glycerin from bovine tallow biodiesel and technical glycerin from soy biodiesel process. Due to commercial unavailability of a capable burner for burning glycerin, a swirl burner was developed for crude and technical glycerin combustion, but it was also used successfully in other alternative fuels as raw bovine tallow and diesel. Emissions of sulphur and nitrogen oxides, total hydrocarbons, carbon monoxide, carbon dioxide, formaldehyde, acetaldehyde and acrolein were analyzed and quantified. Similarly, the mutagenic potential of gases was evaluated, as well as the calorific power, thermal decomposition behavior, the associated heat transfer and fundamentals operational parameters such as adiabatic flame temperature, air-fuel ratio and others. A experimental technique for mutagenic and toxicological effects assessment of combustion gases was analyzed and standardized, as well as the calorific power, the associate heat transfer and fundamentals operational parameters. The study was developed using a fully instrumented flame tube furnace, a swirl burner, continuous gas analyzers, a chromatograph, a thermogravimetric analyzer, automatic data acquisition systems and other auxiliary equipment. The mutagenic potential of the combustion gases was studied on biosensor Tradescantia clone KU-20 assay, using chambers of intoxication and biological analytical techniques previously developed and others specially adapted. The results were compared with the performance of diesel at similar conditions and finding that the direct combustion of crude glycerin is a feasible process. In addition, the emissions of CO, NOx, \'SO IND.2\' and THC were 39%, 75%, 69% and 38% correspondingly smaller than those of diesel. The particulate matter emitted by crude glycerin combustion and even more, by technical glycerin, was several times higher than those emitted by the diesel. Also, the emission of acrolein detected in flue gas from crude glycerin (214 ppbv), apparently have not represents danger to the population. Simultaneously was observed that the energy produced from crude glycerin was 61% and 58% cheaper than the energy from diesel and technical glycerin respectively under similar conditions. But certainly, it was found that the crude glycerin combustion is a more complex process compared with the combustion of conventional fuels.

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Carriço, Camila Santana. "Desidratação de glicerol a acroleína, em fase gasosa, sobre catalisadores derivados do precursor lamelar de estrutura MWW." reponame:Repositório Institucional da UFBA, 2012. http://www.repositorio.ufba.br/ri/handle/ri/11733.

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108 f. Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2013-04-08T14:18:11Z No. of bitstreams: 1 Dissertação - Camila Santana Carriço.pdf: 3281348 bytes, checksum: a3b9881e9a61204bb28727d3345e0e1e (MD5) Approved for entry into archive by Ana Hilda Fonseca(anahilda@ufba.br) on 2013-06-06T15:31:43Z (GMT) No. of bitstreams: 1 Dissertação - Camila Santana Carriço.pdf: 3281348 bytes, checksum: a3b9881e9a61204bb28727d3345e0e1e (MD5) Made available in DSpace on 2013-06-06T15:31:43Z (GMT). No. of bitstreams: 1 Dissertação - Camila Santana Carriço.pdf: 3281348 bytes, checksum: a3b9881e9a61204bb28727d3345e0e1e (MD5) Previous issue date: 2012 CAPES O aproveitamento do glicerol excedente pela conversão catalítica a produtos de maior valor agregado vem sendo bastante estudado no sentido de dar um destino mais nobre a este coproduto, valorizando a cadeia produtiva do biodiesel. Dentre os processos de conversão catalítica do glicerol destaca-se a sua desidratação a acroleína, um produto de grande interesse da Química Fina, que pode ser utilizada como matéria-prima para a produção de ácido acrílico, polímeros superabsorventes produtos farmacêuticos, entre outros. Os zeólitos são catalisadores bastante ativos para a desidratação do glicerol a acroleína, devido às suas propriedades ácidas e texturais, mas sua principal limitação é a rápida desativação por formação de coque, como resultado da acidez excessiva e dos pequenos diâmetros de poros encontrados nestes materiais. Uma alternativa promissora é o uso de materiais derivados de zeólitos de precursores lamelares, que permitem ajuste das propriedades ácidas e texturais através de processos de pilarização e exfoliação. Neste trabalho, o precursor lamelar de estrutura MWW foi sintetizado nas razões molares SiO2/Al2O3 = 30, 50 e 80, e convertidos ao zeólito MCM-22 por calcinação, ao derivado pilarizado com SiO2, conhecido como MCM-36 e ao derivado exfoliado, denominado ITQ-2. As amostras foram caracterizadas por DRX, FTIR, TG/DTG, análise textural, MEV e TPD-NH3. Os materiais foram avaliados na reação de desidratação do glicerol à acroleína em fase gasosa e os parâmetros reacionais temperatura, tempo de contato (W/F) e concentração de glicerol foram ajustados com o zeólito MCM-22 na razão molar SiO2/Al2O3 = 30. As condições que favoreceram maiores conversões e seletividades foram empregadas para avaliar os materiais MCM-36 e ITQ-2. Os difratogramas de raios-X comprovaram que a síntese dos materiais foi bem sucedida, apresentando os picos característicos da topologia MWW. A análise textural mostra uma diminuição do volume de microporos e um aumento do volume de mesoporos, consistente com os processos de pilarização e exfoliação do precursor lamelar de estrutura MWW. O processo de exfoliação aumenta a acessibilidade aos sítios ácidos, enquanto a pilarização provoca o bloqueio dos sítios ácidos de natureza zeolítica e criação de novos sítios ácidos devidos aos pilares de SiO2. O melhor desempenho do MCM-36 na conversão de glicerol pode ser associado a sua dupla porosidade, a qual não permite que os canais/sítios ativos sejam obstruídos pela formação de resíduos carbonáceos, e consequentemente, permite que este material seja ativo por mais tempo, no entanto apresenta baixa seletividade a acroleína e formação de subprodutos gasosos. O ITQ-2 mostrou-se altamente seletivo a acroleína, resultado da maior densidade de sítios ácidos e maior acessibilidade aos sítios zeolíticos presentes nas semicavidades superficiais das lamelas. Em todos os materiais o aumento da razão molar SiO2/Al2O3 resulta num decréscimo da conversão do glicerol e da seletividade à acroleína. O principal mecanismo de desativação destes materiais é a formação de coque, que pode ser eliminado por tratamento em atmosfera oxidante a 500°C. O ITQ-2 apresentou uma boa recuperação em três ciclos reacionais Salvador

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Ferreira, Daiani Cecchin. "Desenvolvimento de um método para determinação simultânea de compostos carbonílicos tóxicos durante a vinificação e avaliação do risco da exposição a estes compostos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/165143.

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Propriedades benéficas são associadas ao consumo moderado de vinho devido à presença dos compostos fenólicos. Uma dose diária de vinho de até 200 ou 300 mL é sugerida para mulheres e homens, respectivamente. Entretanto, dentre os compostos presentes nos vinhos, podem ser encontrados compostos carbonílicos tóxicos, como o formaldeído, acroleína, acetaldeído, furfural e carbamato de etila, os quais tem sido associados a efeitos adversos à saúde humana, incluindo o câncer. O objetivo deste trabalho foi desenvolver e validar um método para a quantificação simultânea destes compostos tóxicos através da microextração em fase sólida no modo headspace associada à cromatografia gasosa acoplada à espectrometria de massas quadrupolar no modo de monitoramento de íons selecionados (HS-SPME- GC/qMS-SIM) e caracterizar o risco relacionado à exposição a estes compostos. Quatro etapas da vinificação (uva, mosto, após a fermentação alcoólica e vinho) e vinhos comercialmente disponíveis foram analisados com o uso da GC/qMS-SIM após verificar as coeluições através da cromatografia gasosa bidimensional abrangente acoplada ao detector de espectrometria de massas por tempo de voo (GC×GC- TOFMS). O acetaldeído e a acroleína derivatizados coeluíram na primeira dimensão cromatográfica com o limoneno e o hexanoato de metila, respectivamente. Em função disso, foram escolhidos como íons quantificadores na análise por GC/qMS, íons que não foram encontrados no espectro de massas dos compostos coeluídos. Os parâmetros de validação (LOD, LOQ, recuperação, repetibilidade e reprodutibilidade) mostraram que a HS-SPME-GC/qMS-SIM é adequada para quantificar simultaneamente os cinco compostos tóxicos. A acroleína foi encontrada em concentrações similares na uva e mosto, e não foi detectada após a fermentação alcoólica e no vinho. O acetaldeído foi detectado em menores concentrações no mosto e em maiores níveis após a fermentação alcoólica. A concentração de furfural foi maior nas uvas do que nas demais etapas. O carbamato de etila não foi detectado nas etapas da vinificação e nos vinhos comerciais. Os níveis de formaldeído ficaram entre os valores de LOD e LOQ em todas as etapas da vinificação e nos vinhos comerciais. Além disso, nos vinhos comercialmente disponíveis, a acroleína foi encontrada em 50% das amostras, o acetaldeído e o furfural estavam presentes em todas as amostras. O único composto cuja ingestão pode representar risco a saúde é a acroleína. Dessa forma, este estudo contribuiu para identificar os pontos críticos de controle relacionados à presença de compostos tóxicos durante a vinificação, incluindo a produção do acetaldeído durante a fermentação alcoólica e a contaminação das uvas com acroleína e furfural através do ar atmosférico. Além disso, os resultados da ocorrência destes compostos tóxicos em vinhos comercialmente disponíveis poderão contribuir para a criação de uma legislação nacional que estabeleça limites dos mesmos nesta bebida. Beneficial properties are associated with moderate consumption of wine due to the presence of phenolic compounds. A daily intake of wine of up to 200 or 300 mL is suggested for women and men, respectively. However, toxic carbonyl compounds such as formaldehyde, acetaldehyde, acrolein, furfural and ethyl carbamate can be found among the compounds present in wines, which have been associated with adverse effects on human health, including cancer. The objective of this work was to develop and validate a method for simultaneous quantification of these toxic compounds through headspace solid phase microextraction associated with gas chromatography with quadrupole mass spectrometric detection in selected-ion monitoring mode (HS-SPME-GC/qMS-SIM) and characterize the risk related to exposure to these compounds. Four vinification steps (grape, must, after alcoholic fermentation and wine) and commercially available wine were analyzed using GC/qMS-SIM after checking the coelutions by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC×GC-TOFMS). The derivatized acetaldehyde and acrolein coeluted in the first chromatographic dimension with limonene and methyl hexanoate, respectively. Based on this, were chosen as quantifiers ions in GC/qMS analysis, ions that were not found in the mass spectra of the coeluted compounds. The validation parameters (LOD, LOQ, recovery, repeatability and reproducibility) showed that HS-SPME-GC/qMS-SIM is adequate to simultaneously quantify the five toxic compounds. Acrolein was found at similar concentrations in grape and must, and was not detected after alcoholic fermentation and in wine. Acetaldehyde was detected at lower concentrations in the must and at higher levels after alcoholic fermentation. The concentration of furfural was higher in the grapes than in the other stages. Ethyl carbamate was not detected in the vinification steps and in commercially wine. Formaldehyde levels were between the LOD and LOQ values at all stages of winemaking and commercial wines. In addition, in commercially available wines, acrolein was found in 50% of samples, acetaldehyde and furfural were present in all samples. The only compound whose intake may pose a health risk is acrolein. Thus, this study contributed to identify critical control point related to the presence of toxic compounds during winemaking, including the production of acetaldehyde during alcoholic fermentation and the contamination of grapes with acrolein and furfural through atmospheric air. In addition, the results of the occurrence of these toxic compounds in commercially available wines may contribute to the creation of national legislation that establishes limits of the same in this drink.

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Böhnke, Harald. "Sorptions- und transient kinetische Experimente bei der heterogen katalysierten Partialoxidation ungesättigter Aldehyde." [S.l. : s.n.], 2000. http://elib.tu-darmstadt.de/diss/000033/.

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Mohr, Christian. "Struktur-Reaktivitätsbeziehungen in der Hydrierung von Acrolein an Gold-Träger-Katalysatoren." [S.l. : s.n.], 2002. http://elib.tu-darmstadt.de/diss/000243.

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Kunert, Jan. "Untersuchungen zur Acroleinoxidation am Mo-V-W-Mischoxidsystem über die Präparationsstrategie zum katalytischen Verständnis /." Phd thesis, [S.l. : s.n.], 2003. https://tuprints.ulb.tu-darmstadt.de/386/1/Kunert_Teil1.pdf.

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Heterogen katalysierte Partialoxidationen an Mischoxiden erfordern multifunktionale Katalysatoren, die in der Lage sind, das organische Molekül und den für die Reaktion notwendigen Sauerstoff zu aktivieren. Stammt dieser aus dem Festkörper selbst, so muss der Katalysator zusätzlich die Eigenschaft haben, sich zu regenerieren. Das in dieser Arbeit untersuchte Mischoxidsystem für die Partialoxidation von Acrolein zu Acrylsäure basiert auf den Übergangsmetallen Molybdän, Vanadium und Wolfram. Diese komplexen Fähigkeiten des Katalysatorsystems galt es durch eine geeignete Präparationsstrategie gezielt zu modifizieren. Es konnte gezeigt werden, dass eine eindeutige Rückkopplung zwischen Katalysatorperformance und Präparationsparametern und Zwischenstufen besteht. Dies eröffnet eine systematische Weiterentwicklung der Präparationsstrategie und damit ein vertieftes Verständnis für die Wirkungsweise des aktiven Kontakts. Für die Entwicklung einer Präparationsstrategie wurde der Grundgedanke eines rationalen Katalysatordesigns aufgegriffen. Es wurden sowohl strukturelle/morphologische Untersuchungsmethoden (z. B. XRD, REM, EDX, TG/DTA, DRIFTS, etc.) als auch kinetische (u. a. TG/DTA-MS, Mikroreaktor für transiente Messungen) für die Erfassung der einzelnen Präparationsschritte eingesetzt. Abschließend wurden die präparierten Mischoxide bzgl. ihrer katalytischen Eigenschaften mittels TP-Experimenten untersucht. In diesem Zusammenhang lässt sich die Problematik des Reaktionsnetzwerkes schematisch auf eine Selektivoxidation und die konkurrierenden unselektiven Parallel- bzw. Folgereaktion reduzieren. Für die notwendigen Untersuchungen wurde u. a. eine Sprühtrocknungsapparatur konzipiert und gebaut, eine TG/DTA-Analytik für die Durchführung von transienten Experimenten angepasst und optimiert sowie eine bestehende Apparatur zur Durchführung von transienten Methoden weiterentwickelt.

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Bispo, Vanderson da Silva. "Investigação dos mecanismos biológicos de detoxificação de aldeídos α,β- insaturados em ratos SODG93A modelo para ALS." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-07122015-105825/.

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A lipoperoxidação gera diversas espécies carbonílicas altamente reativas dentre as quais se destacam acroleína (ACR), malondialdeído (MDA), 4-hidroxi-2-hexenal (HHE) e 4-hidroxi-2-nonenal (HNE). A principal via endógena de metabolização desses compostos é através de conjugação com glutationa por ação da glutationa-S-tranferase. Contudo, diversos trabalhos têm mostrado que dipeptídeos contendo histidina, tal como a carnosina (CAR), também podem formar conjugados com aldeídos e auxiliar na detoxificação desses compostos. Em nosso trabalho adutos de CAR com ACR, HHE, HHEd5, HNE e HNEd11 foram sintetizados, purificados e caracterizados. A reação da CAR com ACR foi estudada em detalhes. Resultados mostraram que a carnosina reage com acroleína formando 03 produtos principais: m/z = 265, m/z = 283 e m/z = 303, sendo este último mais estável e mais abundante. Dados de RMN H1, COSY e HSQC permitiram elucidar a estrutura dessa molécula (m/z = 303) e propor uma rota de reação. Em seguida, uma metodologia baseada em cromatografia líquida acoplada à espectrometria de massas do tipo \"Ion Trap\" (ESI+ HPLC/MS-MS) foi desenvolvida e validada para quantificação simultânea dos adutos sintetizados. Pelo método desenvolvido é possível quantificar com precisão 25 pmol de CAR-HHE, 1 pmol de CAR-ACR e 1 pmol de CAR-HNE com um coeficiente de variação de aproximadamente 10 % e acurácia de 98 % (HHEd5 e HNEd11 foram usados como padrão interno). Análise em urina de adultos não fumantes mostraram que os produtos sintetizados estão presentes na urina de humanos em concentrações de 3,6 ± 1,4; 2,3 ± 1,5 e 1,3 ± 0,5 nmol / mg de creatinina, respectivamente para CAR-ACR, CAR-HHE e CAR-HNE. Em ratos transgênicos SODG93A modelo para esclerose lateral amiotrófica (ELA), a suplementação da dieta dos animais com 35 ± 5 mg carnosina/animal/semana melhorou a manutenção do peso e a sobrevida dos animais. Análises dos adutos sintetizados em amostras de músculo sugerem que a metabolização de aldeídos esteja comprometida nesses animais e que a carnosina poderia funcionar como \"scavenger\" para esses compostos. Esses resultados comprovam que dipeptídeos de histidina atuam na detoxificação de compostos carbonílicos e participa de suas vias de excreção. Além disso, a caracterização da estrutura e desenvolvimento de método sensível de detecção abre a possibilidade de utilização desses adutos como biomarcadores de estresse redox e exposição a aldeídos. Lipid peroxidation generates reactive carbonyl species, including 4-hydroxy-2-nonenal (HNE), acrolein (ACR), 4-hydroxy-2-hexenal (HHE) and malondialdehyde (MDA). One major pathway of aldehyde detoxification in vivo is through conjugation with glutathione catalyzed by glutathione-S-transferases or, alternatively, by conjugation with endogenous histidine containing dipeptides, such as carnosine (CAR). The reaction of CAR with ACR was investigated in an effort to assess its possible biological role. One stable adduct was isolated by reverse-phase HPLC and characterized on the basis of extensive spectroscopic measurements. The proposed reaction route for product formation involves the reaction of the CAR amino group with ACR via a Schiff base formation followed by dehydration and cyclization through Michael addition in the imidazole ring forming an instable compound with m/z = 265. The subsequent reaction with another molecule of ACR followed by cyclization gives rise to the final product with m/z = 303.A highly sensitive method involving HPLC-MS analysis was developed for the simultaneous accurate quantification of CAR- ACR, CAR-HHE and CAR-HNE adducts in human urinary samples from non-smoking adults. This methodology permits quantification of 10 pmol CAR-HHE and 1 pmol of CAR-ACR and CAR-HNE. Adduct levels in urine were 3.6 ± 1.4, 2.3 ± 1.5, 1.3 ± 0.5 nmol/mg of creatinine, respectively to CAR-ACR, CAR-HHE and CAR-HNE. In SODG93A transgenic rats model to amyotrophic lateral sclerosis (ALS), the food supplementation of the animals with 35 ± 5 mg carnosine/animal/week improve de body weight and the life span of the ALS treated group. Analysis of the synthesized adducts in muscle sample showed suggest than aldehyde metabolization is compromised in this animals and that may be carnosine work like a scavenger for these compounds. Our results indicate that carnosine adduction can be an important detoxification route of α,β -unsaturated aldehydes. Moreover, carnosine adducts quantification may be useful as redox stress indicator in vivo.

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Gomes, Lays Nobrega. "Resposta de células pulpares a biomodificação do colágeno pela acroleína e seu efeito sobre a resistência máxima a tração da matriz dentinária e resistência da união resina-dentina /." Araraquara, 2020. http://hdl.handle.net/11449/192504.

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Orientador: Josimeri Hebling Resumo: Objetivo: Investigar a citotoxicidade transdentinária da acroleína (ACR) sobre células pulpares e a resistência máxima à tração (RMT) da matriz dentinária e resistência da união (RU) resina-dentina após a biomodificação do colágeno dentinário por esse agente promotor de ligações cruzadas. Métodos: Discos de dentina (0,4 mm de espessura) foram obtidos de molares humanos hígidos e adaptados em câmaras pulpares artificiais. Células MDPC-23 foram semeadas na superfície pulpar desses discos e a superfície oclusal foi condicionada com ácido fosfórico por 15s. Sobre a dentina condicionada foi aplicado (n=9): água deionizada (controle), ACR 0,02%, 0,01%, 0,005%, glutaraldeído 5% (GD) ou peróxido de hidrogênio 3%. Após 60s, a superfície foi lavada e as câmaras foram incubadas por 24h. Foi avaliada a viabilidade das MDPC-23 (alamarBlue) aderidas na parede pulpar dos discos e os extratos foram aplicados em novas MDPC-23 e HDPCs (células da polpa dental humana) cultivadas em placas de cultura. Após 24h, essas células foram avaliadas quanto a viabilidade, atividade de fosfatase alcalina (ensaio da timolftaleína), presença de nódulos de mineralização (Alizarin red) e expressão gênica de ALPL, DSPP, MMP2, MMP9 e IL1B (PCRq). Vinte cinco molares adicionais foram seccionados para obter espécimes de dentina (n=50) que foram completamente desmineralizados com ácido fosfórico por 24h. Os espécimes de matriz dentinária foram tratados por 60s com: água, ACR 0,02%, 0,01%, 0,005% ou GD 5% e submetid... (Resumo completo, clicar acesso eletrônico abaixo) Abstract: Objective: To investigate the transdentinal cytotoxicity of acrolein (ACR) on pulp cells, as well as the ultimate tensile strength (UTS) of the dentin matrix, and the strength of resin-dentin bonds after dentin collagen biomodification with this cross-linker. Methods: Dentin disks (0.4 mm thick) were cut from sound human molars and adapted in artificial pulp chambers. MDPC-23 were seeded on the pulpal side of the disks and the occlusal surface was etched with phosphoric acid for 15s. The etched dentin was treated with (n=9): deionized water (control), 0.02%, 0.01%, 0.005% ACR, 5% glutaraldehyde (GD), or 3% hydrogen peroxide. After 60s, the surface was rinsed, and the chambers were incubated for 24h. The viability of MDPC-23 cells seeded on the disk was assessed (alamarBlue) and the extracts were applied on new MDPC-23 and HDPCs (human dental pulp cells) seeded in culture plates. After 24h, the viability of the cells was investigated as well as the activity of alkaline phosphatase, presence of mineralized nodules (Alizarin red) and ALPL, DSPP, MMP2, MMP9 and IL1b gene expression (qPCR). Additional twenty-five human molars were sectioned to obtain dentin specimens (n=50) which were completely demineralized in 10% phosphoric acid for 24h. The specimens were treated for 60s with: water, 0.02%, 0.01%, 0.005% ACR or 5% GD, and then submitted to a mechanical test to determine the UBS. Finally, flat dentin surfaces prepared in 40 human molars were etched with phosphoric acid and trea... (Complete abstract click electronic access below) Mestre

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Födisch, Ringo. "Heterogen katalysierte Hydrierreaktionen in konventionellen und Mikrostrukturreaktoren in der Flüssig- und Gasphase." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968853854.

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Campos, Ana Flávia Pinheiro de. "Avaliação de catalisadores na reação de desidratação do glicerol." Universidade Federal de Uberlândia, 2011. https://repositorio.ufu.br/handle/123456789/15190.

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Environmental problems generated due the widespread use of fossil fuels has led the search for new energy alternatives. In this context, the biodiesel emerged as a product of great interest. However, the increase in the biofuel production leads to the production of large amounts of glycerol, which emerges as a cheap raw material with high functionality to produce different products such acrolein (currently it is obtained by selective propylene oxidation), 1,2-propanediol and others. In this study, previously, was performed a theorical and thermodynamic study of acrolein production from glycerol and others products. Catalytic tests from glycerol under different acid solid catalysts, such as materials based on alumina, niobium and zeolite, temperatures between 275 and 350°C and atmospheric pressure were performed. The catalysts were characterized by nitrogen physisorption, X-ray diffraction (XRD), temperature programmed desorption (TPD) and temperature programmed oxidation (TPO). The aim of this study is to evaluate the performance of catalysts and reaction temperature influence, in the formation of products as acrolein and acetol, main products of the reaction of dehydration of glycerol. Problemas ambientais gerados devido ao uso generalizado de combustíveis fósseis têm levado a busca por novas alternativas energéticas. Nesse contexto, o biodiesel, surge como um combustível de grande interesse. Entretanto, o aumento na produção deste biocombustível acarreta a produção de grandes quantidades de glicerol, que por sua vez, desponta como uma matéria-prima com baixo valor de mercado e de grande funcionalidade para produção de diferentes produtos, tais como a acroleína (atualmente obtido pela oxidação seletiva do propeno), 1,2-propanodiol, entre outros. Neste trabalho, previamente foi realizado um estudo teórico e termodinâmico da reação de formação da acroleína e outras possíveis reações que podem ocorrer no sistema reacional. Testes catalíticos a partir do glicerol sob diferentes catalisadores sólidos ácidos, tais como materiais a base de alumina, nióbio e zeólita, temperaturas entre 275 e 350°C e pressão ambiente foram realizados. Os catalisadores foram caracterizados por fisissorção de nitrogênio, difratometria de raio-x (DRX), dessorção à temperatura programada (TPD) e oxidação à temperatura programada (TPO). O objetivo deste trabalho é a avaliação do desempenho de catalisadores e da influência da temperatura reacional na formação de produtos como a acroléina e acetol, principais produtos da reação de desidratação do glicerol. Mestre em Engenharia Química

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Nguyen, Thanh-Binh. "Mesoporous catalysts for ammoxidation of acrolein to acrylonitrile." Doctoral thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/29821.

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L’acrylonitrile est une matière première importaite de l’industrie des polymères, produite à grande échelle à partir de matériaux d’origine fossile. Les tendances de recherche actuelles pour une industrie chimique plus écologique favorisent l’utilisation de molécules plateformes d’origine biologique telles que le glycérol. De plus, la conception de catalyseurs est un élément essentiel pour développer ces produits. Les catalyseurs hétérogènes, en particulier les catalyseurs à base d’oxydes métalliques mésoporeux jouent un rôle majeur dans l’industrie pétrochimique. Par conséquent, l’objectif de cette thèse est de développer des catalyseurs nouveaux, efficaces et utiles, à base d’oxydes métalliques mixtes pour l’ammoxydation de l’acroléine ex-glycérol en acrylonitrile. Sur la base des catalyseurs traditionnels pour l’ammoxydation du propène/propane en acrylonitrile, une série de catalyseurs à base de molybdates et d’antimonates supportés sur une silice mésoporeuse a été développée. Tout d’abord, les molybdates de bismuth ont été supportés sur la silice mésoporeuse KIT-6 en utilisant une méthode de gabarit solide (hard template). Différentes phases de molybdates de bismuth ont été synthétisées, caractérisées et testées pour l’ammoxydation de l’acroléine en acrylonitrile. Les conditions réactionnelles ont été soigneusement optimisées à différentes températures, débits et rapports molaires de réactifs. Les catalyseurs obtenus ont montré une bonne activité catalytique, une sélectivité et une stabilité, en particulier les échantillons contenant des phases mixtes de molybdates de bismuth. Deuxièmement, une série de mélanges de molybdates et d’antimonates supportés sur une silice mésoporeuse à l’aide d’une méthode de gabarit flexible (soft-template) a également été étudiée. Cette nouvelle méthode de soft template a été développée en utilisant la technique d’auto-assemblage induite par évaporation (EISA) et de tensioactifs comme agents structurants. Les catalyseurs obtenus présentaient une surface spécifique élevée et un grand volume de pores. De plus, les résultats catalytiques indiquent que les molybdates mixtes jouent un rôle majeur dans l’ammoxydation de l’acroléine. Certains des catalyseurs ont été choisis pour étudier le mécanisme de réaction de l’ammoxydation de l’acroléine en acrylonitrile. Parce que l’oxygène (l’air) et l’ammoniac sont des réactifs dans ce procédé, les effets des lacunes d’oxygène et de la réduction par l’ammoniac sur l’activité catalytique ont ensuite été étudiés. Les résultats obtenus ont démontré que les catalyseurs ayant plus de lacunes d’oxygène et qui étaient facilement réduits par l’ammoniac présentaient une activité catalytique plus élevée. Tous les catalyseurs contenant des molybdates ont montré une bonne activité catalytique et une bonne sélectivité pour l’ammoxydation de l’acroléine. Ainsi, un nouveau mécanisme de réaction a été proposé pour l’ammoxydation de l’acroléine sur les catalyseurs à base de molybdates. Acrylonitrile is a raw material in polymer industry with a large scale demand and it has been produced from fossil origin. Current research trends for a greener chemical industry are promoted by using platform molecules of biological origin such as glycerol. Designing catalysts becomes an essential part to develop these products. Heterogeneous catalysts, especially mesoporous metal oxide catalysts, play a major role in petrochemical industry. Therefore, the scope of this thesis is to develop new, effective and useful mesoporous catalysts for ammoxidation of ex-glycerol acrolein to acrylonitrile. Based on the traditional catalysts for propene/propane ammoxidation to acrylonitrile, a series of molybdates and antimonates based catalysts supported in mesoporous silica was developed. First, bismuth molybdate oxides were supported in mesoporous silica KIT-6 using the hard-templating method. Different phases of bismuth molybdates were synthesized, characterized and tested for ammoxidation of acrolein to acrylonitrile. The reaction conditions were carefully optimized at different temperatures, flow rates and reactant ratios. The obtained catalysts showed good catalytic activity, selectivity and stability, especially, the samples containing mixed phases of bismuth molybdates. Second, a series of molybdate and antimonate mixtures supported on mesoporous silica using a soft-templating method was also studied. This new soft-templating method was developed based on the evaporation induced self-assembly (EISA) technique and dual surfactants as structure directing agents. The obtained catalysts exhibited high specific surface area and large pore volume. In addition, the catalytic results indicated that molybdates in mixture state play a major role in acrolein ammoxidation. Some of the above catalysts were chosen to study the reaction mechanism of acrolein ammoxidation to acrylonitrile. Because oxygen (air) and ammonia are reactants in this process, the effects of oxygen vacancies and ammonia reduction on catalytic activity were then investigated. The obtained results demonstrated that the catalysts having more oxygen vacancies and being readily reduced by ammonia showed higher catalytic activity. All catalysts containing molybdates showed good catalytic activity and selectivity for acrolein ammoxidation. Thus, a new reaction mechanism was proposed over molybdates oxides as catalysts.

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Wibawanta, Sandra Anni Setyowati. "Catalytic partial oxidation of propylene for acrolein production." Thesis, Curtin University, 2011. http://hdl.handle.net/20.500.11937/584.

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The objective of this thesis, which was to develop a high activity catalyst with 95% selectivity to acrolein at 350oC, was successfully achieved by Mo12Bi1.5Fe0.8Co3.5W0.6K0.04Si1.4P0.7Ox catalyst. The screening tests even when using propylene feed-stocks straight from the refinery by-product without prior purification have proven the consistency in catalytic performance, thereby confirming the reliability of the preparation technique. In trying to make the catalyst more robust, it was physically modified to spheres and pellets and was used successfully in a fixed bed reactor.

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Durant, Stormy R. "In Vitro Exploration of Functional Acrolein Toxicity with Cortical Neuronal Networks." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1157516/.

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Acrolein is produced endogenously after traumatic brain injury (TBI) and is considered a primary mechanism for secondary damage occurring after TBI. We are using frontal cortex networks derived from mouse embryos and grown on microelectrode arrays in vitro to monitor the spontaneous activity of networks and the changes that occur after acrolein application. Networks exposed to acrolein exhibit a biphasic response profile. An initial increase in network activity, followed by a decrease to 100% activity loss in applications ≥ 50 µM. In applications below 50 µM, acrolein was not toxic but generated activity instability with coordinated but irregular population busts lasting for up to 6 days. The increase in activity preceding toxicity may be linked to a decrease in free spermine, a free radical scavenger that modulates Na+, K+, Ca+ channels as well as NMDA, Kainate, and AMPA receptors. Action potential wave shape analysis after 20 and 30 µM acrolein application revealed a concentration-dependent 15-33% increase in peak to peak amplitude within minutes after exposure. For the same concentrations of acrolein (50 µM), the time required to reach 100% activity loss (IT100) was longer in serum-free medium than in medium with 5% serum, in which IT100 values were reduced by a factor of 4. The greater toxicity in the presence of serum may be explained by acrolein adducts on serum proteins. These reaction products have been shown by other labs to be toxic in cell culture. This in vitro system could be used to expand biochemical analyses such as acrolein-induced spermine depletion and may provide an effective platform for investigating cell culture correlates of secondary TBI damage.

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Santos, Regina Claudia Rodrigues dos. "Catalisadores BimetÃlicos de Ãxidos de MoâCu (Ni ou Co) Suportado em Alumina para ConversÃo do Glicerol a IntermediÃrios QuÃmicos." Universidade Federal do CearÃ, 2016. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=16858.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico A viabilidade econÃmica da produÃÃo do biodiesel depende do uso do glicerol, subproduto com estrutura multifuncional, considerado matÃriaâprima bio-renovÃvel, de grande potencial para ser transformado a combustÃveis ou produtos quÃmicos de maior valor agregado. Com o intuito de contribuir para o desenvolvimento dessa linha de pesquisa, foi realizado estudo do potencial catalÃtico da γ-Al2O3 modificada com Ãxido de molibdÃnio e promotores (Cu, Ni ou Co), na reaÃÃo de desidrataÃÃo do glicerol a intermediÃrios quÃmicos com aplicaÃÃo industrial. A estratÃgia foi sintetizar esferas de Al2O3 por mÃtodo hÃbrido, as quais apresentam interessantes propriedades estruturais, texturais e quÃmicas para em seguida impregnar com precursores dos metais via mÃtodo nÃo-convencional (Pechini). A composiÃÃo dos materiais foi escolhida com o objetivo de avaliar o efeito bifuncional causado pela combinaÃÃo das propriedades Ãcido/bÃsicas e redox de catalisadores de molibdÃnio suportado em alumina. Para fins comparativos foi testado catalisador comercial Ni-Mo/Al2O3 com elevada acidez e porosidade. Os catalisadores foram caracterizados por: ICP-OES, FRX, TGA/DTA, DRX, MEV, IV, TPR-H2, TPD-CO2, isotermas de adsorÃÃo/dessorÃÃo de N2, e acidez atravÃs de adsorÃÃo de piridina. O desempenho dos catalisadores foi avaliado na desidrataÃÃo do glicerol, sob fluxo de N2 ou H2, a 1atm e 250ÂC. As mudanÃas na atividade e seletividade devido Ã troca do gÃs de arraste estÃo associadas a alteraÃÃes nas propriedades Ãcido/redox dos catalisadores, como sugerido pelas medidas de acidez e TPR-H2. AcroleÃna foi o principal produto observado para todos os catalisadores, porÃm a amostra contendo cobre (CuMoAl), mostrou maior atividade catalÃtica e superior seletividade a Ãlcool alÃlico, bem como produÃÃo do 1-propanol; o que estÃ associado a transferÃncia de hidrogÃnio. Essa seletividade concorda com resultados de TPR-H2, que mostram maior influÃncia do cobre sobre a reduÃÃo do Ãxido de molibdÃnio, quando comparado aos promotores (Co ou Ni). Ao final sÃo propostos passos reacionais envolvidos na conversÃo do glicerol a Ãlcool alÃlico. The economic viability of biodiesel production depends of the use of glycerol, by-product with multifunctional structure, considered a bio-renewable feedstock of great potential to be transformed to fuel or higher value-added chemicals products. In order to contribute to the development of this research area, study was carried out in order to explore the catalytic potential γ-Al2O3 modified with molybdenum oxide and promoter (Cu, Ni or Co) in the glycerol dehydration reaction to chemical intermediates with industrial application was performed. The strategy was to synthesize Al2O3 spheres by hybrid method with interesting structural, textural and chemical properties for then impregnating with precursors of metals via unconventional method (Pechini). The material composition was chosen with the aim of evaluating the bifunctional effect caused by the combination of acid-base and redox properties of molybdenum catalysts supported on alumina. For comparison was evaluated commercial Ni-Mo/Al2O3 catalyst with high acidity and porosidade. The catalysts were characterized for: ICP-OES, XRF, TGA/DTA, XRD, SEM, IR, H2-TPR, TPD-CO2, N2 adsorption/desorption isotherms, and acidity measurements through pyridine adsorption. The catalytic performance was evaluated in the glycerol dehydration under N2 or H2 flow at atmospheric pressure and 250ÂC. The modification in the activity and selectivity due to the change of carrier gas are attributed to the changes of acid/redox properties of the catalyst, as suggested by acidity measurements and TPR-H2. Acrolein was the main product observed for all catalysts, but the cupper containing catalyst (CuMoAl) showed higher catalytic activity and, and superior selectivity to allyl alcohol, as well as the production of 1-propanol, which is due to the hydrogen transfer. This selectivity agrees with H2-TPR results, which show stronger effect of the copper over the molybdenum oxide reduction, if compared to the others promoter (Co or Ni). At the end it is proposed the reaction steps mechanism for the glycerol conversion to allyl alcohol.

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Mohammad, Amjad Basha. "Density functional studies of acrolein hydrogenation on silver surfaces." kostenfrei, 2008. http://mediatum2.ub.tum.de/doc/650535/650535.pdf.

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Belcher, Jason Lamar Walker Robert Harold. "Acrolein (2-propenal) a potential alternative to methyl bromide /." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SUMMER/Agronomy_and_Soils/Dissertation/Belcher_Jason_27.pdf.

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Slott, Valerie L. "Regulation of the teratogenicity of acrolein in the rat." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74022.

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Simmons, Lee Julian Rodríguez-Kábana R. "Developing alternatives to methyl bromide a focus on acrolein (2-propenal) /." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SPRING/Entomology_and_Plant_Pathology/Dissertation/Simmons_Lee_19.pdf.

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Fansuri, Hamzah. "Catalytic partial oxidation of propylene to acrolein: the catalyst structure, reaction mechanisms and kinetics." Thesis, Curtin University, 2005. http://hdl.handle.net/20.500.11937/2280.

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Bismuth molybdates have long been known as active catalysts for selective oxidation of olefins. There are several phases of bismuth molybdates but only three of them are known to be active for partial oxidation of propylene to acrolein, namely, α, β, and γ bismuth molybdates. A significant amount of work has been carried out and reported in the literature, aiming to understand the reaction mechanisms so as to control the reaction process. It has been revealed that the oxidation reaction follows the redox mechanisms and lattice oxygen plays a key role as the main oxygen source for the reaction and controls the catalyst performance. The properties of the lattice oxygen are influenced by the bulk crystalline structure of the catalyst. Therefore, it is possible that the crystal structure influences the performance of the catalyst in promoting the partial oxidation reaction. However, there appears to be a lack of detailed reports in the literature on the relationship between the bulk crystal structure and the activity and selectivity of the catalyst for the partial oxidation reaction. The work reported in this thesis has been designed to achieve an improved understanding of the catalyst structure in relation to the activity and selectivity of the catalyst for the partial oxidation of propylene to acrolein.In order to fulfil the objectives of this study, several investigation steps have been taken, namely 1) acquiring and analysing the catalyst structural parameters under real reaction conditions as well as at room temperature by means of neutron diffraction and X-ray diffraction, 2) obtaining kinetics from experimentation using a packed-bed reactor operating under differential reactor mode so as to eliminate the mass diffusion effect, and 3) developing and proposing reaction mechanisms which contain events that occur on the crystalline structure of the catalysts, particularly lattice oxygen, during the reaction. Characterisation of the structure of the catalysts has been carried out by means of In-situ neutron diffraction, which has the ability to probe the crystal structure at atomic level. The structure is characterised under simulated reaction conditions to investigate the dynamics of the crystal structure, particularly lattice oxygen, during the reaction. The In-situ diffraction studies have uncovered the relationship between the crystal structure of bismuth molybdates and their selectivity and activity towards the catalytic partial oxidation of propylene to acrolein. The possible active lattice oxygen in the bismuth molybdate structures has been identified. The active lattice oxygen ions are responsible for maintaining redox balance in the crystal lattice and thus control the catalyst activity and selectivity. Mobile oxygen ions in the three bismuth molybdate crystal phases are different. The mobile oxygen ions are O(1), O(11), and O(12) in the α phase; O(3), O(11), O(16), and O(18) in the β phase; and O(1) and O(5) in the γ phase.The mobile lattice oxygen ions are proposed to be the source of the oxidising oxygen responsible for the selective oxidation of propylene to acrolein. One common feature of all mobile oxygen ions, from a catalyst crystal structure point of view, is that they are all related to molybdenum ions rather than bismuth ions in the lattice. By modifying the physical and chemical environment of the molybdenum oxide polyhedra, it is possible to modify the catalyst selectivity and activity. The diffraction diagnoses have also shown that molybdenum oxide polyhedra in all bismuth molybdate are unsaturated. In contrast, the bismuth oxide polyhedra are over charged. The co-existence of molybdenum ions that are co-ordinately unsaturated with bismuth ions that are over valence-charged promote the formation of allyl radical such as those found in the partial oxidation of propylene to acrolein. The molybdenum ions become propylene-adsorbing sites while the bismuth ions are the active sites to attract hydrogen from the adsorbed propylene, leading to the formation of the allyl intermediate. Oxygen ions from the mobile lattice oxygen are a more moderate oxidant than molecular oxygen. With their mild activity, the partially oxidised products are the main products such as acrolein and formaldehyde when oxygen ions react with the allyl intermediate while more complete combustion products such as carbon oxides and organic acids become the side products.Investigation into the kinetics and reaction mechanisms has revealed the aforementioned evidence to support the role of the mobile lattice oxygen ions in the partial oxidation of propylene to acrolein. The kinetic experiments have employed the power rate law to model the kinetic data. The model shows that the reaction orders in propylene and oxygen concentrations are a function of the reaction temperature. The reaction order in propylene increases with reaction temperature, from 0.6 at 300°C to 1.0 at 450°C for all the bismuth molybdate catalysts, while the reaction order in oxygen decreases from 0.6 at 300°C to 0 at 450°C. The activation energies are 99.7, 173, and 97.7 kJ.mol-1 for α-Bi2Mo3O12, β-Bi2Mo2O9, and γ-Bi2MoO6, respectively. The changes in reaction orders with respect to propylene and oxygen indicate that the reaction occurs through the redox mechanisms, using the mobile lattice oxygen. The structural dynamics identified earlier explains the decrease in the acrolein selectivity at high temperatures (ca above 390°C). At these temperatures, the mobile oxygen becomes more mobile and more active. As a result, as the mobility of the oxygen ions increase, their reactivity also increases. The increase in the oxygen reactivity leads to unselective, complete oxidation reaction, forming the complete oxidation products CO2 and H2O. The reduction-reoxidation of bismuth molybdate is controlled by the diffusion of oxygen ions in the lattice, because the reduction sites do not have to be adjacent to the oxidation sites. The oxygen diffusion rate is in turn controlled by how mobile the lattice oxygen ions are.Hence, the mobile oxygen ions discussed earlier control the catalyst activity in catalysing the reaction of propylene partial oxidation. The examination of several reaction mechanism models has given further evidence that the propylene partial oxidation to acrolein occurs via the redox mechanism. In this mechanism, the rate of acrolein formation depends on the degree of fully oxidised sites in the bismuth molybdate. The oxidised sites affect the apparent reaction orders in propylene and oxygen and thus control the kinetics of partial oxidation of propylene to acrolein. The more easily the reduced catalysts are reoxidised, the more active the catalysts in converting propylene to acrolein. A set of reaction steps has been proposed, which adequately reassembles the reaction mechanism. Side product reactions are also identified and included in the mechanisms. The present thesis has revealed a much detailed insight into the role of lattice oxygen in the catalytic partial oxidation of propylene to acrolein over bismuth molybdates and established the relationship between structure and activity and selectivity of the catalyst. This work has laid a foundation for future catalyst design to be based on structural knowledge of the catalysts.

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25

Liebig, Carsten. "Indirect ammoxidation of glycerol in to acrylonitrile via the intermediate acrolein." Thesis, Lille 1, 2012. http://www.theses.fr/2012LIL10065.

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Suite au caractère fini des réserves de charbon, pétrole et gaz, nous sommes obligés de trouver des alternatives renouvelables pour substituer les ressources fossiles comme source d’énergie et matière première pour l’industrie chimique. Parmi les nombreuses exemples ou la biomasse est déjà utilisé comme alternative aux ressources fossiles, on peut notamment citer le biodiésel. Ce dernier est produit à grande échelle par la transesterification de l’huile végétale. Cependant, le glycérol est formé comme sous-produit inévitable qui doit être valorisé pour augmenter la compétitivité du procédé. Parmi les différentes possibilités de valorisation, la déshydratation pour donner l’acroléine est le plus prometteur. Ce dernier peut ensuite être converti en acrylonitrile par ammoxidation catalytique. Dans ce projet, les deux réactions – déshydratation et ammoxidation – ont d’abord été étudiés séparément puis ensuite combinés en utilisant un réacteur de type tandem. Pour l’étape de déshydratation, un catalyseur à base de WO3/TiO2 été utilisé. Pour l’ammoxidation, les catalyseurs ont été choisis parmi les oxydes métalliques à base d’antimoine, de fer, de vanadium et de molybdène. Notamment le catalyseur à base de Sb-Fe-O montre des bonnes performances, c’est pourquoi le ratio Sb/Fe été étudié plus en détail. La présence de la phase FeSbO4 est directement corrélée à la sélectivité en acrylonitrile. De plus, on constate une augmentation de la sélectivité en cours de la réaction, ce qui s’explique avec la formation de FeSbO4 in operando. Après l’optimisation des paramètres clefs à l’aide d’un plan d’expérience, les deux réactions ont été combinées. Le rendement maximal obtenu est de 40% Due to the depleting reserves of coal, oil and natural gas, we are forced to find renewable alternatives to replace the fossil feedstock for the production of energy and chemical products. An example where renewables are already used to substitute fossil feedstocks is biodiesel. The latter is produced by transesterification of vegetable oils and fats whereby glycerol is formed as a by-product. Due to the large amounts produced, the glycerol needs to be valorized to increase the economical viability of the overall process. One very promising use of glycerol is the dehydration of glycerol into acrolein, which can then be further converted to acrylonitrile. The corresponding ammoxidation is catalyzed by metal oxides.In the present project, both reaction steps were studied separately at first - with focus on the ammoxidation of acrolein - and then connected in a tandem reactor setup finally.For the dehydration of glycerol to acrolein WO3/TiO2 catalysts were used, while oxide catalysts containing antimony, iron, vanadium and molybdenum were developed for the ammoxidation step. Especially, the Sb-Fe-O catalysts were found highly selective and the influence of Sb/Fe ratio was subsequently studied. The presence of a FeSbO4 mixed phase was correlated to a high selectivity to acrylonitrile. Further, an increase in selectivity to acrylonitrile with the reaction time was observed, which was explained by the progressive formation of additional amounts of FeSbO4 over the catalysts during the reaction. After optimizing the key reaction parameter within a design of experiments, both reaction steps were connected in a tandem reactor. A maximum yield in acrylonitrile of 40 % was obtained

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26

Yan, Wei. "Gas phase conversion of sugars to valuable C3 chemicals." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/5504.

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Thesis (Ph. D.)--University of Missouri-Columbia, 2008. The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on July 31, 2009) Includes bibliographical references.

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27

Liebig, Carsten [Verfasser]. "Indirect ammoxidation of glycerol into acrylonitrile via the intermediate acrolein / Carsten Liebig." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2013. http://d-nb.info/103860317X/34.

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28

Schulz, Kirk H. "The partial oxidation of propene to acrolein over single-crystal Cu₂O." Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/37413.

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29

Borowiec, Anita. "New acrolein production route starting from alcohols mixtures over FeMo-based catalysts." Thesis, Lille 1, 2016. http://www.theses.fr/2016LIL10153/document.

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L'acroléine est le plus simple des aldéhydes insaturés, qui - en raison de sa réactivité élevée - trouve des applications comme produit intermédiaire dans l'industrie chimique (par exemple pour la synthèse d'acide acrylique et la production de méthionine (i.e. acide aminé essentiel)). Récemment, on a observé une augmentation de la demande mondiale de produits dérivés de l'acroléine, qui devrait croître de façon continue au cours des prochaines années. De nos jours, l’acroléine est obtenue par oxydation du propylène, et donc ce procédé est basé sur des ressources fossiles qui ne cessent de décroitre. Ce travail propose une nouvelle méthode de production d'acroléine à partir de matières premières renouvelables – un mélange d’alcools formé de méthanol et d'éthanol. Cette réaction a été étudiée et optimisée en travaillant sur : les conditions de réaction via l’établissement d’un plan d’expériences afin de minimiser le nombre de tests catalytiques à réaliser, les modifications de la formulation catalytique FeMoOx (i.e. différents rapports Mo / Fe, température de calcination, et l’ajout d’éléments basiques (e.g. La, Ce) pendant la synthèse) et enfin l’utilisation d’un second catalyseur pour balancer les propriétés acides-bases nécessaires à l’obtention de notre molécule cible Acrolein is the simplest unsaturated aldehyde, which - due to its high reactivity - finds applications as an intermediate in the chemical industry (e.g., for acrylic acid and methionine production). Recently, a worldwide demand increase of acrolein derivatives was observed, which is expected to continuously grow within the next years. However, nowadays acrolein is commercially obtained by propylene oxidation, where the raw material comes from fossil resources. This work proposes a new method of acrolein production starting from renewable feedstock – methanol and ethanol mixture. This reaction was approached by reaction conditions optimization (i.e. Design of Experiment method do decrease the number of catalytic tests and save time), FeMoOx modifications (e.g. various Mo/Fe ratios, calcination temperature, and basic elements addition) and a second catalyst utilization (e.g. single commercial oxides and silica-based materials) in order to balance the acid base properties

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30

Tonelli, Matteo. "Design of new catalysts for the mild oxidation of propene to acrolein." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10325.

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31

Van, Vuuren Peter. "Selective oxidation of propene to acrolein on α-Bi₂Mo₃O₁₂ nano-particles". Thesis, Stellenbosch : University of Stellenbosch, 2005. http://hdl.handle.net/10019.1/2972.

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Thesis (MScEng (Process Engineering))--University of Stellenbosch, 2005. Although selective oxidation catalysts are widely used and extensively studied for their industrial and academic value, their complex mechanisms are, to a large extent, still unclear. The field of so-called allylic (amm)oxidations reactions was chosen for further investigation, in particular the simplistic selective oxidation of propene to acrolein over an α-Bi2Mo3O12 catalyst. One of the most important approaches in selective oxidation is to try to correlate the physicochemical properties of catalysts with their catalytic performance (activity and selectivity). The most interesting, and seemingly most widely invoked parameter, is lattice oxygen mobility. The problem, however, is the difficulty encountered in measuring oxygen mobility. It is hypothesised that the depth of oxygen utilisation and lattice oxygen mobility of bismuth molybdate during the partial oxidation of propene to acrolein may be determined by measuring the rate of acrolein formation and lattice oxygen usage over a range of discrete particle sizes that could be synthesised using reverse micelle technology. Catalyst Preparation A preliminary investigation into the reverse micelle technique showed that discrete nanosized particles could be synthesised, but that there was no size control over the outcome and that, in most cases there were some degree of particle agglomeration. It was also found that nanorod formation occurred due to adsorbtion of surfactant. More in-depth investigation had to be done in order to achieve particle size control and the liberation of the calcined α-Bi2Mo3O12 catalyst particles required for kinetic experiments. Simple precipitation methods, the catalyst calcination step, and the formation and stability of reverse micelles were investigated. A simple precipitation method to prepare α-Bi2Mo3O12, suitable to be integrated into the reverse micelle technique was found by buffering the mixture of bismuth nitrate and ammonium molybdate solutions with an excess of molybdate. This prevented the pH from decreasing below a critical value of 1.3 (at which β-Bi2Mo2O9 forms as an impurity). The excess molybdenum caused the formation of MoO3 in the calcined product, which was selectively and successfully removed using a warm ammonium wash followed by a water rinse and a recalcination step. XRD of a temperature range calcination shows that the calcination starts at temperatures as low as 200°C and almost complete calcination of the catalyst at 280°C. DSC analyses show a 47.15 J/g crystal formation peak only at 351°C. The Mo18O56(H2O)8 4- anion or its double, Mo36O112(H2O)16 8-, is responsible for the formation of α-Bi2Mo3O12 in the precipitation calcination reaction. Reverse micelles were investigated using a Malvern Zetasizer and showed a complex dynamic system in which the reverse micelle sizes and size distributions change over time as a function of surfactant and aqueous concentrations, the salt used and aqueous phase salinity. Although much was accomplished in this study, more investigations into the constituent steps of the reverse micelle technique are needed to develop a method to synthesise the range of discrete catalyst particle sizes required for kinetic studies. Kinetic Studies For the purpose of kinetic experiments a metal reactor was found to be superior to that of a glass reactor. The reactor rig was adequate for these kinetic studies but do not meet the requirements for detailed reaction order experiments. The analysing apparatus could not measure CO2 formation accurately and it had to be calculated using a carbon balance. Only the model proposed by Keulks and Krenzke [1980a] was able to describe the kinetic result, but the model parameter describing the oxidative state of the catalyst surface could not be calculated due to the lack compatibility between published data. Values were awarded to this parameter so to give an Arrhenius plot which corresponded to published data. The parameter describing the oxidative state vs. temperature took on a function that was consistant with the reasoning of Keulks and Krenzke [1980a]. Comprehensive preliminary kinetic studies are needed, both in catalyst reduction and reoxidation, in order to determine the reaction conditions, explore more advanced kinetic models and investigate model parameters that are theoretically and/or empirically obtainable and quantifiable.

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32

Kawanishi, Masanobu. "Molecular mechanisms of mutations induced by environmental pollutants, 3-nitrobenzanthrone, crotonaldehyde and acrolein." Kyoto University, 1998. http://hdl.handle.net/2433/157051.

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本文データは平成22年度国立国会図書館の学位論文(博士)のデジタル化実施により作成された画像ファイルを基にpdf変換したものである Kyoto University (京都大学) 0048 新制・課程博士 博士(工学) 甲第7521号 工博第1762号 新制||工||1124(附属図書館) UT51-98-W265 京都大学大学院工学研究科環境地球工学専攻 (主査)教授松井三郎, 教授森澤眞輔, 教授齋藤烈 学位規則第4条第1項該当

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33

Li, Xin. "Selective oxidation of propylene to acrolein over vanadium and niobium doped bismuth molybdates." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 131 p, 2009. http://proquest.umi.com/pqdweb?did=1654493551&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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34

Bauer, Robert. "The Role of Src Kinase Activation in Lung Epithelial Alterations in Response to the a,b-Unsaturated Aldehyde Acrolein." ScholarWorks @ UVM, 2016. http://scholarworks.uvm.edu/graddis/597.

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Cigarette smoke (CS) exposure is the leading cause of preventable death in the United States contributing to over 480,000 deaths a year with over 300 billion dollars in CS related costs spent per year. While the dangers of CS exposure have been studied and characterized for decades being largely attributed to reactive oxygen species and oxidative stress, increasing evidence suggests that reactive aldehydes in CS, specifically the α,β-unsaturated aldehyde acrolein, are responsible for many of the negative pathologies associated CS exposure. Previous work has shown that acrolein can bind directly to a number of cellular proteins containing redox sensitive cysteine residues. The non-receptor tyrosine kinase Src contains nine cysteine residues and is known to be activated in response to CS and oxidative stress. Despite being the first characterized and one of the most widely studied oncogenes, the exact mechanism for Src activation remains unclear. In the current studies we examined the effects of acrolein on Src activation and the resulting outcomes on the lung epithelium in an effort to better understand how reactive electrophiles in CS contribute to the development of lung disease. To determine the effects of acrolein on Src activation, we first exposed NCI-H292 cells to acrolein and measured activity by western blot. We observed an increase in Src activity detected by an increase in Src phosphorylation at Y416 and an increase in phosphorylation of Src target proteins Caveolin1 and p120. Interestingly the increase in activation occurred without dephosphorylation of the inhibitory phosphorylated tyrosine Y527. Using biochemical-labeling strategies we identified Src as a direct target of acrolein adduction in vitro and in vivo, and we used mass spectrometry to confirm acrolein adduction to cysteine residues C245, C277 and C487, all which have been implicated in a redox dependent Src activation mechanism. Furthermore, increased Src activity following acrolein exposure was confirmed using an in vitro kinase activity assay and recombinant Src in a cell free system. To study the effects of acute acrolein exposure on lung epithelial function we exposed cultured mouse tracheal epithelial cells (MTECs) to acrolein and show impaired epithelial barrier function, measured by a decrease in trans epithelial resistance (TER) and increased epithelial permeability to FITC-dextran, which could be prevented using the Src inhibitor PP2. Src inhibition also attenuated acrolein-induced loss of E-cadherin and ZO-1. Acute exposure of C57BL/6 mice to acrolein (5 ppm for 4 hrs) led to increased epithelial permeability, measured by enhanced leakage of i.v. injected FITC-dextran into the airspaces, and induction of HO-1 in the lung while chronic acrolein exposure resulted features of epithelial to mesenchymal transition including a reduction of E-cadherin, increased vimentin, increased expression of MMP9 and increased collagen deposition. Chronic acrolein exposure in vitro resulted in a reduction of E-cadherin that could be prevented using the Src inhibitor AZD0530. Together our studies demonstrate that Src is a direct target for acrolein and plays an important role in epithelial alterations due to acrolein exposure. This work provides further insight into a potential mechanism involved in the development of cigarette smoke related disease and could provide a potential target for novel therapeutics.

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35

Deshmukh, Hitesh S. "Role of Matrix Metalloproteinases in Acrolein-Induced Mucin 5 (Subtype A and C) Increase." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1141149563.

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36

Fansuri, Hamzah. "Catalytic partial oxidation of propylene to acrolein : the catalyst structure, reaction mechanisms and kinetics /." Curtin University of Technology, Department of Chemical Engineering, 2005. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=16386.

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Bismuth molybdates have long been known as active catalysts for selective oxidation of olefins. There are several phases of bismuth molybdates but only three of them are known to be active for partial oxidation of propylene to acrolein, namely, α, β, and γ bismuth molybdates. A significant amount of work has been carried out and reported in the literature, aiming to understand the reaction mechanisms so as to control the reaction process. It has been revealed that the oxidation reaction follows the redox mechanisms and lattice oxygen plays a key role as the main oxygen source for the reaction and controls the catalyst performance. The properties of the lattice oxygen are influenced by the bulk crystalline structure of the catalyst. Therefore, it is possible that the crystal structure influences the performance of the catalyst in promoting the partial oxidation reaction. However, there appears to be a lack of detailed reports in the literature on the relationship between the bulk crystal structure and the activity and selectivity of the catalyst for the partial oxidation reaction. The work reported in this thesis has been designed to achieve an improved understanding of the catalyst structure in relation to the activity and selectivity of the catalyst for the partial oxidation of propylene to acrolein. In order to fulfil the objectives of this study, several investigation steps have been taken, namely 1) acquiring and analysing the catalyst structural parameters under real reaction conditions as well as at room temperature by means of neutron diffraction and X-ray diffraction, 2) obtaining kinetics from experimentation using a packed-bed reactor operating under differential reactor mode so as to eliminate the mass diffusion effect, and 3) developing and proposing reaction mechanisms which contain events that occur on the crystalline structure of the catalysts, particularly lattice oxygen, during the reaction. Characterisation of the structure of the catalysts has been carried out by means of In-situ neutron diffraction, which has the ability to probe the crystal structure at atomic level. The structure is characterised under simulated reaction conditions to investigate the dynamics of the crystal structure, particularly lattice oxygen, during the reaction. The In-situ diffraction studies have uncovered the relationship between the crystal structure of bismuth molybdates and their selectivity and activity towards the catalytic partial oxidation of propylene to acrolein. The possible active lattice oxygen in the bismuth molybdate structures has been identified. The active lattice oxygen ions are responsible for maintaining redox balance in the crystal lattice and thus control the catalyst activity and selectivity. Mobile oxygen ions in the three bismuth molybdate crystal phases are different. The mobile oxygen ions are O(1), O(11), and O(12) in the α phase; O(3), O(11), O(16), and O(18) in the β phase; and O(1) and O(5) in the γ phase. The mobile lattice oxygen ions are proposed to be the source of the oxidising oxygen responsible for the selective oxidation of propylene to acrolein. One common feature of all mobile oxygen ions, from a catalyst crystal structure point of view, is that they are all related to molybdenum ions rather than bismuth ions in the lattice. By modifying the physical and chemical environment of the molybdenum oxide polyhedra, it is possible to modify the catalyst selectivity and activity. The diffraction diagnoses have also shown that molybdenum oxide polyhedra in all bismuth molybdate are unsaturated. In contrast, the bismuth oxide polyhedra are over charged. The co-existence of molybdenum ions that are co-ordinately unsaturated with bismuth ions that are over valence-charged promote the formation of allyl radical such as those found in the partial oxidation of propylene to acrolein. The molybdenum ions become propylene-adsorbing sites while the bismuth ions are the active sites to attract hydrogen from the adsorbed propylene, leading to the formation of the allyl intermediate. Oxygen ions from the mobile lattice oxygen are a more moderate oxidant than molecular oxygen. With their mild activity, the partially oxidised products are the main products such as acrolein and formaldehyde when oxygen ions react with the allyl intermediate while more complete combustion products such as carbon oxides and organic acids become the side products. Investigation into the kinetics and reaction mechanisms has revealed the aforementioned evidence to support the role of the mobile lattice oxygen ions in the partial oxidation of propylene to acrolein. The kinetic experiments have employed the power rate law to model the kinetic data. The model shows that the reaction orders in propylene and oxygen concentrations are a function of the reaction temperature. The reaction order in propylene increases with reaction temperature, from 0.6 at 300°C to 1.0 at 450°C for all the bismuth molybdate catalysts, while the reaction order in oxygen decreases from 0.6 at 300°C to 0 at 450°C. The activation energies are 99.7, 173, and 97.7 kJ.mol-1 for α-Bi2Mo3O12, β-Bi2Mo2O9, and γ-Bi2MoO6, respectively. The changes in reaction orders with respect to propylene and oxygen indicate that the reaction occurs through the redox mechanisms, using the mobile lattice oxygen. The structural dynamics identified earlier explains the decrease in the acrolein selectivity at high temperatures (ca above 390°C). At these temperatures, the mobile oxygen becomes more mobile and more active. As a result, as the mobility of the oxygen ions increase, their reactivity also increases. The increase in the oxygen reactivity leads to unselective, complete oxidation reaction, forming the complete oxidation products CO2 and H2O. The reduction-reoxidation of bismuth molybdate is controlled by the diffusion of oxygen ions in the lattice, because the reduction sites do not have to be adjacent to the oxidation sites. The oxygen diffusion rate is in turn controlled by how mobile the lattice oxygen ions are. Hence, the mobile oxygen ions discussed earlier control the catalyst activity in catalysing the reaction of propylene partial oxidation. The examination of several reaction mechanism models has given further evidence that the propylene partial oxidation to acrolein occurs via the redox mechanism. In this mechanism, the rate of acrolein formation depends on the degree of fully oxidised sites in the bismuth molybdate. The oxidised sites affect the apparent reaction orders in propylene and oxygen and thus control the kinetics of partial oxidation of propylene to acrolein. The more easily the reduced catalysts are reoxidised, the more active the catalysts in converting propylene to acrolein. A set of reaction steps has been proposed, which adequately reassembles the reaction mechanism. Side product reactions are also identified and included in the mechanisms. The present thesis has revealed a much detailed insight into the role of lattice oxygen in the catalytic partial oxidation of propylene to acrolein over bismuth molybdates and established the relationship between structure and activity and selectivity of the catalyst. This work has laid a foundation for future catalyst design to be based on structural knowledge of the catalysts.

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37

Watzek, Nico Verfasser], Elke [Akademischer Betreuer] Richling, and Gerhard [Akademischer Betreuer] [Eisenbrand. "Acrylamid und Acrolein: Toxikokinetik hitzeinduzierter Kontaminanten in Lebensmitteln / Nico Watzek. Betreuer: Elke Richling ; Gerhard Eisenbrand." Kaiserslautern : Universitätsbibliothek Kaiserslautern, 2012. http://d-nb.info/1022850598/34.

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38

Oehmke, Sebastian [Verfasser], and Martin [Akademischer Betreuer] Kaltschmitt. "Prozessentwicklung zur biotechnologischen Produktion von Acrolein aus Nebenprodukten der Bioethanolherstellung / Sebastian Oehmke. Betreuer: Martin Kaltschmitt." Hamburg-Harburg : Universitätsbibliothek der Technischen Universität Hamburg-Harburg, 2014. http://d-nb.info/1051373824/34.

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39

Watzek, Nico [Verfasser], Elke Akademischer Betreuer] Richling, and Gerhard [Akademischer Betreuer] [Eisenbrand. "Acrylamid und Acrolein: Toxikokinetik hitzeinduzierter Kontaminanten in Lebensmitteln / Nico Watzek. Betreuer: Elke Richling ; Gerhard Eisenbrand." Kaiserslautern : Universitätsbibliothek Kaiserslautern, 2012. http://nbn-resolving.de/urn:nbn:de:hbz:386-kluedo-31102.

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40

Rünz, Meike [Verfasser], and Elke [Akademischer Betreuer] Richling. "Untersuchungen zur Acrylamid- und Acrolein-Exposition mittels Lebensmittel- und Humanbiomonitoring / Meike Rünz ; Betreuer: Elke Richling." Kaiserslautern : Technische Universität Kaiserslautern, 2018. http://d-nb.info/1155166213/34.

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41

Coffey, Chelsea M. "ANALYTICAL METHOD DEVELOPMENT FOR THE DETECTION AND ANALYSIS OF PROTEIN CARBONYLS." VCU Scholars Compass, 2015. http://scholarscompass.vcu.edu/etd/3737.

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Oxidative stress can result in changes to many biomolecules and also affect their activities. We are interested in protein carbonylation, a type of unnatural oxidation which has been associated with numerous degenerative disease states and is also a consequence of the natural aging process. Protein carbonyls are stable species, but countless analytical barriers exist in terms of their identification. Thus, the main goal of this work was to develop and optimize analytical methods that could be used to help us better understand which, where, and how proteins are being carbonylated. Initial studies involved method validation for carbonylating, tagging, and enriching the model protein human serum albumin (HSA). We have developed a reproducible method of producing carbonylated protein in vitro in which HSA is treated with acrolein to carbonylate cysteines, histidines, and lysines. Protein carbonyls are compatible with various affinity labels and enrichment techniques. We strived to learn more about the efficiencies of various biotin affinity labels and avidin enrichment techniques using quantitative assays and mass spectrometry. Results showed a preference for different affinity labels based on their chemical properties and suggested that monomeric columns are selective for particular peptides. Most recently, method development and validation work was done involving a cleavable biotin tag that enables both enrichment and identification of protein carbonylation modification sites. This affinity tag offered the highest labeling efficiency of all tags tested in the past and greater coverage of modification sites than biotin hydrazide reagents. We applied our analytical methods to two sets of human blood samples. The first sample set was plasma taken from chronic kidney disease (CKD) patients. No carbonylation patterns were elucidated, but this project marked the beginning of blood analyses in which existing protocols were adapted to blood samples. The second sample set was serum/plasma taken from patients with traumatic injuries. We effectively applied our analytical methods to these sample sets and were able to visualize and quantitate temporal protein carbonylation patterns via Western blotting and iTRAQ-based mass spectrometry experiments. ProteoMiner experiments proved successful in that we were able to identify a larger and more diverse amount of carbonylated proteins via mass spectrometry.

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Santos, Maurício Brandão. "Síntese, caracterização e aplicação catalítica do zeólito ferrierita na desidratação de glicerol à acroleína em fase gasosa." Instituto de Química, 2015. http://repositorio.ufba.br/ri/handle/ri/19175.

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Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-04-29T15:57:07Z No. of bitstreams: 1 Dissertação Maurício Brandão dos Santos.pdf: 3641159 bytes, checksum: 88e0cb2e8aa02b484840cb026ee24d5f (MD5) Approved for entry into archive by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-05-12T16:07:25Z (GMT) No. of bitstreams: 1 Dissertação Maurício Brandão dos Santos.pdf: 3641159 bytes, checksum: 88e0cb2e8aa02b484840cb026ee24d5f (MD5) Made available in DSpace on 2016-05-12T16:07:25Z (GMT). No. of bitstreams: 1 Dissertação Maurício Brandão dos Santos.pdf: 3641159 bytes, checksum: 88e0cb2e8aa02b484840cb026ee24d5f (MD5) CAPES A produção de biodiesel no Brasil é hoje uma realidade, mas para que o processo seja economicamente viável faz-se necessário o aproveitamento do glicerol obtido como coproduto. Produtos mais rentáveis podem ser obtidos por diversas rotas catalíticas. A acroleína que é um intermediário químico na produção de ácido acrílico e seus polímeros pode ser obtida pela desidratação de glicerol, em fase gasosa. Esta reação é favorecida sobre catalisadores ácidos, especialmente os zeólitos. Estes materiais são aluminossilicatos microporosos, com estrutura tridimensional e acidez que pode ser ajustada pela razão molar SiO2/Al2O3. A depender da estrutura do zeólito, de sua acidez e propriedades texturais, podem ser obtidas altas conversões e seletividades na desidratação do glicerol a acroleína, em fase gasosa, mas geralmente observa-se rápida desativação pela deposição de coque. Os melhores resultados de conversão de glicerol na literatura foram obtidos com o zeólito H-β e o H-ZSM-5. Porém, apesar do zeólito ferrierita apresentar baixa conversão e da não existência de estudos exploratórios dessa topologia na literatura Kim e colaboradores apontam melhores seletividades a acroleína para o zeólito ferrieita. O zeólito ferrierita (FER) é composto estruturalmente por canais com anéis de dez membros intersectados perpendicularmente a canais formados por anéis de oito membros. A síntese hidrotérmica estática deste zeólito pode ser realizada em meio hidróxido ou fluoreto. Ademais, diferentes composições de gel de síntese são encontradas na literatura utilizando diferentes agentes direcionadores de estrutura. Neste trabalho a síntese do zeólito ferrierita foi realizada utilizando etilenodiamina, em meio hidróxido e piridina e/ou n-butilamina para o meio fluoreto, com diferentes razões molares SiO2/Al2O3. Os materiais foram caracterizados e avaliados cataliticamente na desidratação do glicerol a acroleína em fase gasosa. A utilização de ar sintético como gás de arraste, regenera sítios ácidos coqueados nas primeiras horas de teste catalítico e, mantém a conversão de glicerol e a seletividade a acroleína praticamente constantes nas demais horas de reação. A medida que aumenta a razão SiO2/Al2O3 maior a fração de sítios ácidos moderados e melhor o desempenho catalítico. A temperatura de 300ºC foi a que conduziu melhores atividades para os zeólitos obtidos nos dois meios. A medida que se aumenta o tempo espacial, maior a seletividade a acroleína. A variação da razão H2O/glicerol indicou que, mesmo com o aumento da concentração de glicerol para 50%, se obteve resultados de conversão e seletividades próxima àquelas da solução 36,6%, o que é de extrema importância no aproveitamento de glicerol. Os catalisadores obtidos em meio fluoreto apresentaram ativos na desidratação do glicerol, mesmo apresentando menor densidade total de sítios ácidos. Além disso, estes catalisadores após teste catalítico apresentam baixa desativação e pouca percentagem de coque deposita Biodiesel production in Brazil is a reality, but that the process is economically viable it is necessary the use of glycerol obtained as co-product. Various catalytic routes can obtain most profitable products. The acrolein, which is a chemical intermediate in the production of acrylic acid and its polymers, can be obtained by dehydration of glycerol in the gas phase. This reaction is favored over acid catalysts, especially zeolites. These materials are microporous aluminosilicates with three dimensional structure and acidity can be adjusted by the SiO2/Al2O3 molar ratio. Depending on the zeolite structure, acidity and textural properties can be obtained in high conversions and selectivities dehydration of glycerol to acrolein in the gas phase, but typically observed rapid deactivation by coking. The best conversion of glycerol results in the literature have been obtained with H-β zeolite and H-ZSM-5. However, despite the ferrierite zeolite have low conversion and lack of exploratory studies of this topology in literature Kim et al. point out best selectivities for acrolein ferrieita zeolite. The zeolite ferrierite (FER) consists structurally by channels with rings ten members intersected perpendicularly to channels formed by rings of eight members. The static hydrothermal synthesis of the zeolite can be performed in the middle hydroxide or fluoride. Furthermore, different synthesis gel compositions are found in the literature using different drivers agents structure. In this paper the synthesis of zeolite ferrierite as performed using ethylenediamine in the middle hydroxide and pyridine and/ or n- butylamine in fluoride medium with different SiO2/Al2O3 molar ratios. The materials were characterized and evaluated in the catalytic dehydration of glycerol to acrolein in the gas phase. The use of synthetic air as carrier gas, regenerates the coque in the acid sites in the early hours of catalytic test and keeping the conversion of glycerol and the selectivity to acrolein nearly constant in the remaining hours of reaction. As increases the SiO2/Al2O3 higher the fraction of moderate acid sites and the best catalytic performance. The temperature was 300°C led to the best activities for the zeolites obtained in two ways. As one increases the space time, the higher the selectivity to acrolein. The variation of the ratio H2O/glycerol indicated that even with increasing glycerol concentration for 50% conversion was obtained results and those of the next solution selectivity 36.6%, which is extremely important in the use of glycerol. The catalysts obtained in medium fluoride had assets in glycerol dehydration, even with lower total density of acid sites. Further, these catalysts after the catalytic test and deactivation have low low percentage of deposited coke.

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Harand, Kristina Marie. "Assessment of Acrolein-induced Toxicity Using In-vitro Modeling to Evaluate the Role of PARP Inhibitors in Reducing Cytotoxicity." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6091.

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Acrolein is an electrophilic α, β-unsaturated aldehyde. Additionally, acrolein is a metabolite of the antineoplastic alkylating agent cyclophosphamide and is implicated in off-target effects, including to bladder hemorrhagic cystitis and cyclophosphamide-induced cardiotoxicity, both of which have led to serious secondary iatrogenic injury during and following chemotherapy. At low concentrations acrolein inhibits cell proliferation without inducing apoptosis, while at high concentrations may result in secondary apoptosis promotion. This investigation assessed the role of the enzyme poly (ADP-ribose) polymerase (PARP) in acrolein induced toxicity using the established toxicological H9c2 (2-1) cardiomyoblast in vitro model. H9c2 (2-1) cells were plated in 24-well plates at 75,000 cells per well three days prior to testing, followed by acrolein dosing at concentrations between 10 µM and 1000µM for either 30 or 55 minutes. PARP activity was quantitatively measured in total cell lysates using a biotin-avidin-conjugated horseradish peroxidase-TMB reporter system in a 96-well microplate formate. The lowest effective dose of toxicity at 30 minute dosing was found at 25 μM (PARP Activity 1.65-fold control) which returned to baseline at 100 μM; concentrations at or above 250 μM results in significant PARP activity reductions (≤ 0.46-fold control). Biomarkers were further characterized for cytotoxicity (AST presence), and viability (MTT reduction) in order to facilitate mechanistic characterization of PARP-mediated acrolein cardiotoxicity. Investigation of a PARP inhibitor was assessed to explore the intervention for acrolein induced cardiac tissue damage.

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Brinkerhoff, Alexis I. "Assessment of the Role of Poly (ADP-Ribose) Polymerase in Drug-Induced Cardiomyopathy." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6067.

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Drug-induced cardiotoxicity has resulted in a thorough evaluation of patient doses, treatments, and rehabilitation. One of the most commonly prescribed chemotherapeutic agents is cyclophosphamide. The active metabolite, acrolein, is one of the most potent inducers of cardiomyopathy. In this study, research was conducted on the H9c2 (2-1) cardiomyocyte cell line derived from the embryonic myocardium of rattus norvegicus to assess its competency for evaluation of the change in poly (ADP-ribose) polymerase (PARP) activity. The application of this model to study the effects of acrolein on PARP activation was chosen as an ideal determinant of cell damage produced by nitrogen mustards. To verify the legitimacy of this model, cardiomyocytes were exposed to acrolein in varying concentrations and time durations with a subsequent protein concentration measurement determined through the BCA Protein Assay. After the normalization of samples through volume adjustments and verification of sufficient protein, other aliquots were subjected to a PARP Assay in order to measure PARP activity. PARP was activated at exposure concentrations of 75 μM in all trials, with an average detection of 0.00569 ± 0.001 mU/200ng protein. Other concentrations showed varying degrees of PARP activation, verifying the model’s competency. PARP activation implies the potential use of this model for further research into targeted molecular therapy of PARP inhibition. Therefore, this model has the ability to be used as an assessment tool for the combined use of PARP inhibitors and chemotherapeutic agents; it can be useful for future research investigating the use and efficacy of PARP inhibitors in reducing drug-induced cardiotoxicity.

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Coyle, Jayme. "The Influence of Oxygen Tension and Glycolytic and Citric Acid Cycle Substrates in Acrolein-induced Cellular Injury in the Differentiated H9c2 Cardiac Cell Model." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6487.

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Most in vitro systems employ the standard cell culture maintenance conditions of 95 % air with 5 % CO2 to balance medium pH, which translates to culture oxygen tensions of approximately 20 % - above the typical ≤ 6 % found in most tissues. The current investigation, therefore, aims to characterize the effect of maintenance and toxicant exposure with a particular focus on the α,β-unsaturated aldehyde, acrolein, in the presence of physiologically relevant oxygen tension using a differentiated H9c2 cardiomyoblast subclone. H9c2 cells were maintained separately in 20.1 and 5 % oxygen, after which cells were differentiated for five days, and then exposed to acrolein in media containing varying concentrations of tricarboxylic acid and glycolytic substrates. Cells were then assessed for viability and metabolism via the MTT conversion assay. H9c2 cells were assessed for mechanistic elucidation to characterize contributors to cellular death, including mitochondrial membrane potential (ΔΨm) reductions (JC-1), intracellular calcium influx (Fluo-4), and PARP activation. Exposure to acrolein in differing oxygen tensions revealed that standard culture cells are particularly sensitive to acrolein, but cells cultured in 5 % oxygen, depending on the medium pyruvate concentration, can be rescued significantly. Further, reductions in ΔΨm were reversed by co-exposure of 5-10 mM EGTA for both culture conditions, while intracellular calcium transients were noted only for standard cultures. The results demonstrate significant metabolic reprogramming which desensitizes differentiated H9c2 to acrolein-induced cytotoxicity. Further, PARP and extracellular calcium contribute to the fate of these cells exposed to acrolein, though clotrimazole-associated TRPM2 channels may not be significantly involved. Conclusively, significant alteration of toxicogenic response was noted in this cell line when cultured under physiologically relevant conditions, and may have a substantial impact on the reliability and predictive power and interpretive application of in vitro-based toxicity models cultured under standard culture conditions, depending on the parent tissue.

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Hong, Hea Jin. "Acrolein Modification of Human Apolipoprotein A-I Impairs Binding to Phosphatidylglycerol and Lipopolysaccharide of Gram-Negative Bacteria." Thesis, California State University, Long Beach, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10604454.

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Human apolipoprotein A-I (apoA-I) has been shown to exhibit antimicrobial activity by neutralizing lipopolysaccharides and destabilizing inner membranes of gram-negative bacteria. Previous studies showed that acrolein, a highly reactive αβ unsaturated aldehyde an environmental pollutant and an endogenously generated lipid peroxidation product, modifies ϵ-amino groups of lysine residues in apoA-I. The current study investigated the effect of acrolein exposure on the structure and antimicrobial activity of apoA-I. Acrolein modification was evident by the appearance of apoA-I oligomers due to intermolecular crosslinking, as well as reactivity with an antibody specific for acrolein. Increase of the acrolein to protein ratio resulted in heavily cross-linked apoA-I. Circular dichroism analysis showed that the α-helical content of acrolein-modified apoA-I was decreased but the protein retained α-helicity. The stability of modified proteins was increased. Phosphatidylglycerol binding was strongly affected when apoA-I was modified with acrolein. Lipopolysaccharide binding experiments showed that the binding of acrolein modified apoA-I became weaker than unmodified apoA-I. These results suggest that apoA-I modification by acrolein leads to decreased binding of apoA-I to bacterial membranes making it less potent as an antimicrobial protein.

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Akatsuka, Shinya. "Contrasting genome-wide distribution of 8-hydroxyguanine and acrolein-modified adenine during oxidative stress-induced renal carcinogenesis." Kyoto University, 2007. http://hdl.handle.net/2433/135700.

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Bittencourt, Leonardo da Silva. "Avaliação do potencial do extrato comercial de guaraná (Paullinia cupana) como alternativa preventiva frente à toxicidade induzida em ratos wistar por compostos carbonílicos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/150208.

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Os compostos carbonílicos (CC) são compostos altamente tóxicos. A exposição humana aos CC ocorre a partir da inalação de seus vapores, contato com a pele e ingestão através dos alimentos e geração endógena. Dentre estes CCs, podemos citar, acroleína (ACR), Glioxal (GO), Metil-Glioxal (MGO). O 2-propenal, também conhecido como acroleína (ACR). Este composto é um aldeído eletrofílico, α-β insaturado altamente reativo, incolor, que está presente no ambiente (presente no ar e na água devido à combustão incompleta de madeira, petróleo, carvão, plásticos, tabaco), em alimentos (frituras, bebidas alcoólicas), e ainda é um composto produzido endogenamente (ação de mieloperoxidases na degradação de treonina, degradação de drogas anti-câncer, lipoperoxidação de ácidos graxos poli-insaturados, especialmente no Sistema Nervoso Central- SNC). Fortes evidências (tanto in vitro quanto in vivo) tem mostrado que a ACR gera forte estresse oxidativo (principalmente por depleção de glutationa - GSH), exercendo assim forte influência no início e progressão de doenças crônicas relacionadas ao estresse oxidativo, tais como câncer, doenças neurodegenerativas, aterosclerose, diabetes. Dado a relevância do tema, recentemente a atenção da comunidade científica tem sido focada em entender como a ACR altera o estado-redox celular e principalmente procurar alternativas farmacológicas para atenuar a sua toxicidade. Dentre estas alternativas, estão os compostos com atividade antioxidante e os compostos com atividade diretamente quelante da acroleína, como compostos ricos em grupamentos tióis (SH), compostos nitrogenados (amino compostos) e compostos de ocorrência natural (ácido ascórbico, tocoferol e polifenóis). O uso de plantas medicinais pela população mundial é muito significativo e neste cenário se encaixa o guaraná amazônico (Paullinia cupana, var. Sorbilis). O seu uso tem se disseminado mundialmente principalmente nas bebidas energéticas. Adicionalmente vários estudos produzidos independentemente por diversos grupos de pesquisa sugerem ter o guaraná ação: cardiotônica e cardioprotetora, energética, atividade anti-bacteriana, antioxidante, efeito anti-obesidade, termogênico, atividade contra lesões gástricas, quimiopreventivo, anti-depressivo e anti-mutagênico. Nesta tese demonstramos pela primeira vez que: 1- o extrato de guaraná amazônico possui forte atividade antioxidante frente a várias espécies reativas; 2- atenua o decréscimo de viabilidade induzida por compostos carbonílicos (ACR, GO e MGO) aumentando a viabilidade celular e diminuindo o estresse oxidativo em experimentos com culturas de células SH-SY5Y; 3 – Exerce efeitos antioxidantes no soro de ratos sem exercer efeitos pro-oxidantes no sistema nervoso central e fígado quando administrado sozinho; 4 – Atenua de forma significativa a toxicidade e dano oxidativo induzidos pela acroleína em ratos, se mostrando como uma possível alternativa preventiva promissora para atenuar o dano oxidativo induzido compostos carbonílicos reativos. The carbonyl compounds (CC) are highly toxic compounds. Human exposure to CC occurs from inhalation of vapors, skin contact and ingestion through food and endogenous generation. Among these CCs, such as, acrolein (ACR), Glyoxal (GO), Methyl Glyoxal (MGO). The 2-propenal, also known as acrolein (ACR) is an electrophilic, α-β unsaturated, highly, reactive aldehyde, which is present in the enviroment (in the air and the water due to the incomplete combustion of wood, petroleum, coal, plastics, tobacco), in foods (fried foods, alcoholic beverages), and produced endogenously (myeloperoxidase-induced degradation threonine, degradation of anti-cancer drugs, lipid peroxidation of polyunsaturated fatty acids, especially in the nervous system Central- CNS). Strong evidence (both in vitro and in vivo) has shown that the ACR generates marked oxidative stress (mainly depletion of glutathione - GSH), thereby exerting strong influence on the onset and progression of chronic diseases associated with oxidative stress, such as cancer, neuro-degenerative diseases, atherosclerosis, diabetes. Regarding the relevance, recently the attention of the scientific community has been focused on understanding how the ACR changes the cellular redox-state and mainly seek for pharmacological alternatives to mitigate its toxicity. Among these alternatives are compounds with antioxidant activity and compounds which can directly scavenge acrolein such as thiol (SH), nitrogen compounds (amino compounds) and naturally-occurring compounds (ascorbic acid, tocopherol and polyphenols). The use of medicinal plants for the world's population is very significant, in this scenario we have the Amazon guarana (Paullinia cupana var. Sorbilis). Its use has spread worldwide mainly in energy drinks. Additionally several independente studies suggest guarana’s action: cardiotonic and cardioprotective, energy, anti-bacterial activity, antioxidant, anti-obesity effect thermogenic, activity against gastric lesions, chemopreventive, anti depressant and anti-mutagenic. In this study, we demonstrated for the first time: 1. Amazon guarana has strong antioxidant activity against several reactive species; 2 attenuates the decrease in cabonyl compounds-induced cell viability (ACR, GO, MGO) increasing cell viability and reducing oxidative stress; 3 - exerts antioxidant effects in the serum of rats without exerting pro-oxidant effects in the central nervous system and liver when administered alone; 4 - significantly attenuates the toxicity and oxidative damage induced by acrolein in rats showing a promising preventive alternative to alleviate the oxidative damage induced by reactive carbonyls.

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Osório, Vanessa Moreira. "Desenvolvimento de método para análise de acroleína-DNPH em alimento, ar expirado e ar ambiente utilizando SPME-GC/MS." Universidade Federal de Minas Gerais, 2012. http://hdl.handle.net/1843/SFSA-8YBTTT.

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The carbonyl compounds (CC) are highly toxic compounds. Human exposure to CC occurs from vapors inhalation, dermal absorption and through food ingestion. Therefore, knowledge of the concentration levels of carbonyl compounds is extremely important for the evaluation of environmental contamination and exposure nevertheless in most cases, it is limited to the concentration of formaldehyde and, sometimes, acetaldehyde, neglecting other pollutants no less harmful to human health. A growing concern has been focused to the population that spends most of the day indoors, for instance, houses, offices, shops and leisure environments. Exposure to these environments becomes more critical due to the longer exposure time and high concentrations of pollutants emitted from various sources. This study describes the developemt and validation of gas chromatography methods for determination of acrolein in samples of exhaled air, ambient air and foods fried with different types of oil. For the analysis of exhaled air analytical curve was built with a standard gas generation system through a permeation method. The analyses were carried out by gas chromatography with mass spectrometry detector using the technique of solid phase microextraction (SPME) with polyacrilate fiber (PA). To analyze the breath acrolein has been used a method permeation a system for generating pattern gaseous acrolein to construct the calibration curve. The samples were analyzed by gas chromatography with mass spectrometry detector using the technique of solid phase microextraction (SPME). Two derivatization methods with 2,4-DNPH were developed, one using derivation in solution, for food analyses and another using derivation on PA fiber the analyses of breath and ambient air. The developed methods were validated and applied to real samples of exhaled air from two groups of individuals, smokers and non-smokers. The results showed no statistically significant difference for the groups of smokers and nonsmokers. Average concentration of acrolein in exhaled air of non-smokers was lower when compared to that of smokers. In ambient air, the concentrations of acrolein were greater in parking lots due to emission of acrolein by burning fuels. The methodology developed allowed quantitative analyses of acrolein-DNPH; in various foods (potatoes, cassava, and sausage) fried in different types of oils. The values found in this study were smaller than the maximum established by the World Health Organization (WHO)-2002, which specifies that the concentration of acrolein in food does not exceed 40 g/g. The concentration of acrolein was lower at potatoes fried in soybean oil, due to the lowest content of unsaturated fatty acids present in this oil. In cassava and sausage the concentration of acrolein introduced using corn oil were similar indicating that the oil absorption is independent of the food. The SPME method used for sampling and extraction of acrolein in different matrices showed appropriate, considering the simplicity and rapidity in the analytical process. Gas chromatography with mass spectrometry provided the selectivity, accuracy, sensitivity, and reliability required for the studies. All results found for these parameters were appropriate for the purpose of study Os compostos carbonílicos (CC) são compostos altamente tóxicos. A exposição humana aos CC ocorre a partir da inalação de seus vapores, contato com a pele e ingestão através dos alimentos. Portanto, o conhecimento dos níveis de concentração dos compostos carbonílicos é de extrema importância para avaliações ambientais de contaminação e exposição, porém limita-se na maioria das vezes, apenas a concentração de formaldeído e, algumas vezes, de acetaldeído, deixando de lados outros poluentes não menos nocivos à saúde humana. Uma crescente preocupação tem sido em relação à exposição da população que passa a maior parte do dia em recintos fechados como, por exemplo, casas, escritórios, lojas e ambientes de lazer aos compostos carbonílicos. A exposição nestes ambientes torna-se mais crítica devido ao maior tempo de exposição e às elevadas concentrações de poluentes emitidas por diversas fontes. Neste trabalho, foi desenvolvido e validado um método de cromatografia gasosa para determinação de acroleína, um composto carbonílico tóxico, em amostras de ar expirado, ar ambiente e em alimentos fritos com diferentes tipos de óleo. Para a análise do ar expirado a curva analítica foi construída com um sistema de geração de padrão gasoso de acroleína através de um método de permeação . As análises foram efetuadas por cromatografia gasosa com detector de espectrometria de massas utilizando a técnica de microextração em fase sólida (SPME) com fibra de poliacrilato (PA). Foram desenvolvidos dois métodos de derivatização com 2,4-dinitrodenilhidrazina (2,4-DNPH) para a quantificação de acroleína por SPMEGC/MS, para a análise de alimentos a derivatização foi feita na solução de 2,4-DNPH e para as análises do ar expirado e do ar ambiente a derivatização foi feita na fibra de PA. As metodologias desenvolvidas foram validadas e aplicadas em amostras reais de ar expirado de dois grupos de indivíduos, fumantes e não fumantes. Os resultados obtidos apresentaram diferença estatisticamente significativa para os grupos de indivíduos fumantes e não fumantes. Em média a concentração de acroleína no ar expirado de indivíduos não fumantes foi menor quando comparada à dos indivíduos fumantes. No ar ambiente a concentração de acroleína foi maior nos estacionamentos devido à emissão de acroleína pela queima de combustíveis. A metodologia desenvolvida permitiu uma análise quantitativa de acroleína-DNPH em vários alimentos (batata, mandioca e lingüiça) fritos em diferentes tipos de óleos. Os valores encontrados neste estudo foram menores que o limite máximo estabelecido pela Organização Mundial de Saúde (OMS) - 2002, que especifica que a concentração de acroleína em alimentos não ultrapasse 40 µg/g. A concentração de acroleína foi menor em batata frita em óleo de soja, devido o menor teor de ácidos graxos insaturados presente neste óleo. Em mandioca e lingüiça a concentração de acroleína utilizando óleo de milho apresentou valores próximos indicando que a absorção do óleo independe do tipo de alimento. O método de microextração em fase sólida utilizado para amostragem e extração de acroleína nas diferentes matrizes mostrou-se adequada, considerando a simplicidade e rapidez no processo de análise. A cromatografia gasosa com espectrometria de massas proporcionou a seletividade, precisão, sensibilidade e confiabilidade exigidas para os estudos. Todos os resultados encontrados para estes parâmetros mostraram-se adequados para o propósito de estudo

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Giebeler, Lars [Verfasser]. "Einfluss von Wolfram als Dotierelement auf die Eigenschaften von V2Mo8WxOy-Katalysatoren zur Selektivoxidation von Acrolein zu Acrylsäure / Lars Giebeler." Aachen : Shaker, 2007. http://d-nb.info/1164339982/34.

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Dissertations / Theses on the topic 'Acroleina'

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