Gotowa bibliografia na temat „Electroplating Effluent”

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico<br>Os metais pesados sÃo conhecidos por serem altamente tÃxicos em baixÃssimas concentraÃÃes na Ãgua. Sendo assim, numerosos estudos tem sido dedicados à sua remoÃÃo a limites aceitÃveis do ponto de vista ambiental. Tais pesquisas se concentram, principalmente, no desenvolvimento de uma remoÃÃo eficiente e de baixo custo. Muitos mÃtodos tÃm sido propostos para remoÃÃo de metais pesados, por exemplo, precipitaÃÃo, membranas filtrantes, troca iÃnica e adsorÃÃo. A precipitaÃÃo à um dos mÃtodos que mais vem sendo utilizado embora seja um mÃtodo inadequado no que se refere a impactos ambientais por gerar resÃduos. A casca de coco oferece facilidade natural de ser encontrado e manejado, por isso à um dos materiais mais estudados para fins de reaproveitamento. Este trabalho se propÃe a fazer um estudo de adsorÃÃo de Cu+2 utilizando casca de coco modificado como adsorbente. As modificaÃÃes empregadas foram (a) por polimerizaÃÃo do formaldeÃdo em meio sulfÃrico; b) Tratamento com lÃquido iÃnico e c) EsterificaÃÃo por Ãcido multicarboxÃlicos e multifenÃlicos. Os modelos aplicados para o estudo de isotermas foram de Langmuir, Freundlich, Temkin e Dubinin âRaduschevich. Aplicando o modelo de Langmuir no estudo de adsorÃÃo de Cu(II) no adsorbente modificado BCFB a capacidade mÃxima de adsorÃÃo qm e a constante KL foram 125 mg/g e 1,11x10-1 L.mg-1 para o Cu+2 . Para os adsorbentes BC/LI e BCTÃnico o valor de qm foram 64,5 e 99mg.g-1 , respectivamente enquanto o valor de KL foram 5,3x10-2 e 5,6x10-2 , respectivamente . O modelo cinÃtico que melhor se ajustou ao fenÃmeno foi o de segunda ordem. Os resultados obtidos mostraram que a casca de coco quimicamente modificado à um potencial adsorbente para remoÃÃo de Cu+2. O estudo de coluna foi empregado para verificar a desempenho do adsorbente quando se emprega efluente industrial. Nas condiÃÃes empregadas neste estudo a modificaÃÃo com Ãcido tÃnico foi a que teve melhor desempenho de remoÃÃo. Destaca-se tambÃm a capacidade de reutilizaÃÃo do adsorbente que promove uma diminuiÃÃo do custo operacional quando à considerada sua aplicabilidade numa escala industrial.<br>The heavy metals are known to be highly toxic at very low concentrations in water. At this point, numerous studies have been dedicated to their removal to acceptable limits of an environmental point of view. Such researches are focused mainly in developing an efficient removal and low cost. Many methods have been proposed for removing heavy metals, for example, precipitation, membrane filtration, ion exchange and adsorption. The precipitation is one method that has been used more although an inappropriate method regarding the environmental impact for generating residues. The bagasse, coconut offers natural facility to be found and handled, so it is one of the most studied materials for reuse. This paper aims to make a study of adsorption of Cu 2+ using bagasse as adsorbent modified coconut. The modifications were employed (a) by polymerization of formaldehyde in sulfuric acid medium, b) treatment with ionic lÃguido c) Esterification acid and multicarboxÃlicos multifenÃlicos. The models applied to the study of isotherms were Langmuir, Freundlich, Temkin and Dubinin-Raduschevich. Applying the model in the study of Langmuir Adsorption of Cu (II) adsorbent modified BCFB the maximum adsorption capacity qm and kL were contained 125 mg.g-1 and 1.11 x10-2L.mg for Cu +2. For adsorbentes BC / LI and BCTÃnico the qm value were 64.5 and 99mg.g-1 respectively as kL value were 5.3 x10-2 5.6 x10-2 respectively. The kinetic model that best fit the phenomenon was the second order. The results showed that the coconut coir chemically modified is a potential adsorbent for removing Cu2+. The study column was used to verify the performace of the adsorbent when employing industrial effluent. Under the conditions employed in this study was modified with tannic acid that had shown the best removal performance desempenho removal. Also the reusability of the adsorbent is remarkable since it promotes a lowering cost, considering its applicability on an industrial scale.

The aims of the project were twofold. The initial objective of the study, based on previous results, was to develop an economically viable methodology for immobilizing yeast cells for the treatment of heavy metal-laden waste water. The non-viable yeast cross-linked by 13% (w/v) formaldehyde/1N HNO₃ exhibited satisfactory mechanical strength and rigidity in a continuous-flow column operation. No apparent disruption of the biomass after repeated use was observed. The cost of immobilizing 1kg dry yeast pellets was estimated at less than US$I. Zn uptake capacity of FA-cross-linked pellets, on batch trials, remained similar to that of raw yeast, reflecting that the immobilizing procedure did not hinder its metal removing capacity. In column studies, cation metals were effectively removed by the yeast pellets from aqueous solution at natural pHs, and then recovered completely by washing the pellets in situ with O.1M HCl. The recovered metals were concentrated in such small volumes that recycling or precipitation of them was facilitated. The metal uptake capacity of the regenerated biomass remained constant in comparison with cycle 1, indicating that reuse of the yeast would be possible. In the case of Cr⁶⁺, a gradual breakthrough curve of Cr in the column profile was noted, with a simultaneous reduction of Cr⁶⁺ to Cr³⁺. However, Cr⁶⁺ in the effluent can be markedly minimised either by accumulation onto the biomass or reduction to its trivalent form. Desorption of bound Cr⁶⁺ with either alkali or salt could not accomplish the regeneration of the biomass. A combination of reduction and desorption with FA/HNO₃ appeared promising in regeneration of the saturated biomass at 4°C. The metal sorption capacities of the yeast pellets, on a batch or a fixed-bed system are relatively lower than that of documented sorbents. Apparently more of the yeast pellets would be required for treating a certain volume of waste effluent, than with other sorbents. Therefore Azolla filiculoides was examined as a suitable sorbent for this purpose. This constitutes the second part of the project. Azolla filiculoides, a naturally-abundant water fern, was screened for its metal sorption and recovering capacities, mechanical stability, flow-permeability and reusability. The azolla biomass appeared to have fulfilled the required mechanical criteria during the repeated sorption-desorption column operations. It is water-insoluble and appears flexible under pressure when rinsed with water. These characters are of crucial importance in a continuous-flow system since a column can be operated at high flow rates without apparent compact of the biomass and pressure loss. Therefore, immobilization of the biomass can be avoided. The sorption isotherm data, obtained from batch removal of Cr⁶⁺, showed that the sorption process was effective, endothermic and highly pH dependent. Considerable amounts of Cr⁶⁺ were accumulated at the optimum pHs of 2-2.5. Column sorption of Cr⁶⁺ at a low flow rate and pH of 2.5 showed optimum performance with a total Cr uptake of 50.4mg/g at 60% saturation of the biomass. Removal of Cr⁶⁺ from an electroplating effluent using an azolla column was deemed reasonably satisfactory, although the uptake declined slightly. Desorption of bound Cr⁶⁺ with various desorbents was incomplete, which resulted in a low regeneration efficiency of about 50%. However, removal and recovery of Cr³⁺ using the azolla column was than that of Cr⁶⁺. Desorption of Cr³⁺ from the spent biomass column was accomplished with the recovery of 80% using O.5N H₂SO₄, The regeneration efficiencies for Cr³⁺ removal were up to 90% and demonstrated that the biomass is reusable. Cation metal uptake capacities of azolla, obtained either from batch or column experiments, are reasonably high in comparison with other sorbents. The uptake of Ni or Zn ions from solution is pH dependent showing the optimum pH of around 6 to 6.5, under the current experimental conditions. The sorption kinetics for cation metals was rapid with about 80% of the bound Ni ions being taken up in the first 10 min. The character of rapid binding is extremely important in a column sorption process, especially on a large scale since it favours an optimum uptake of metals at high flow rates. The Ni or Zn uptakes in column sorption were not markedly affected when the flow rates were increased from 80mllh up to 800ml/h for the 5g biomass used. The cation heavy metals removed from waste effluents were recovered in a concentrated solution of small volume. The desorption of bound Ni and Zn ions from the saturated biomass was accomplished with either O.2N HCl or H₂SO₄ that resulted in recoveries of more than 95%. The metals recovered, in the case of Ni and Zn, are identical to that of plating agents ego nickel sulphate or chloride, so that recycling of the metals is possible. An effluent-free, closed loop of Ni or Zn treatment system was proposed, whereby the Ni or Zn ions can be recycled to the plating bath whilst the purified water is fed back to the rinse tanks. Ca and Mg ions, commonly present in the electroplating effluents, appeared to affect sorption of heavy metals by azolla when metal concentrations were relatively low, presumedly through its competitive binding for the shared sites on surfaces of azolla. The data obtained from column sorption of Ni and Zn follows the BDST model well, enabling the application of the model to predicting design parameters for scale-up of the biosorption column system. It is interesting that the values of metal uptake, expressed in molar quantities, obtained on respective single-metal solutions and the multiple metal system, are similar, implying that the mechanisms involved in the sorption of all metal cations are similar and that the binding sites on surfaces of azolla are probably shared by all cation metals. The surface of the biomass provides sites for metal binding estimated in the range of 0.45-0.57mmol/g, based on the current experiments. The biomass has a surface area of 429 m²/g and water retention of 14.3 ml/g. The functional groups on the surface of azolla were partially identified using chemical modification and metal binding comparison. Among the functional groups examined, carboxyl groups, provided by amino acids and polysaccharides, appeared to play an important role in metal cation binding. The infrared spectra of the samples support this conclusion.

Made available in DSpace on 2017-07-10T18:07:59Z (GMT). No. of bitstreams: 1 Alvaro Cesar Dias Alves.pdf: 1860253 bytes, checksum: fce25e3199fa4e1f2d24f3500c996153 (MD5) Previous issue date: 2012-02-24<br>Conselho Nacional de Desenvolvimento Científico e Tecnológico<br>This study aimed to evaluate the efficiency of the process of coagulation/ flocculation and coagulation/flocculation/adsorption combined process for treatment of liquid effluent from the electroplanting industry. Were used the moringa seed as a natural coagulant agent and moringa bark and string bean as adsorbents. Were evaluated the parameters COD, color, pH, turbidity and the concentration of metal ions Cr, Zn, Cu and Ni. In the stage of coagulation/ flocculation were used several concentrations of moringa in salt solution of NaCl 1 M and 0.1M. In the stage of the combined adsorbents were used moringa bark and string beans to determine which of the adsorbent had a better removal efficiency of metals. Tests were also conducted with different ranges of mass for the best adsorbent and variation of pH of the studied effluent. Tests of coagulation/flocculation showed good removal efficiency for the parameters COD, Color, Turbidity and the metals Cr, Zn, Cu and Ni using MO seed in salt solution 1M, these values being 90.49%, 78.34%, 95.13%, 25.29%, 84.30%, 51.11% and 24.74% respectively. In the tests of coagulation/flocculation/adsorption the maximum removal efficiencies were 91.41% for COD, 90.77% for color, 95.31% for Turbidity, 58.36% for Cr, 98.36% for Zn, 97,58% for Cu and 99.11% for Ni. The research showed that after the combined process the electroplanting effluent did not present the necessary characteristics for the released in to water bodies due to the high remaining concentration of Cr (1907.4 mg/L), Color (860 PtCo/L) and COD (330 mg/L). The research for the treatment process demonstrated great effectiveness for most parameters analyzed, however, its necessary to study complementary technologies for this type of treatment effluent in order to achieve an effluent within the release standards into the water bodies.<br>Este trabalho teve como objetivo avaliar a eficiência do processo de coagulação/floculação e do processo combinado de coagulação/floculação/adsorção para tratamento de efluente liquido da indústria galvânica. Foi utilizada a semente de moringa como coagulante natural e a casca e a vagem de moringa como adsorventes. Foram avaliados os parâmetros DQO, Cor, pH, Turbidez e a concentração dos íons metálicos Cr, Zn, Cu e Ni. Na etapa de coagulação/floculação foram utilizadas várias concentrações de moringa em solução salina de NaCl 1M e 0,1M. Na etapa do processo combinado foram utilizados os adsorventes casca e vagem de moringa para determinação do adsorvente com melhor eficiência de remoção dos metais. Também foram realizados ensaios com variação de massa do melhor adsorvente e variação do pH do efluente estudado. Os ensaios de coagulação/floculação mostraram boa eficiência de remoção dos parâmetros DQO, Cor, Turbidez e dos metais Cr, Zn, Cu e Ni utilizando semente de MO em solução salina 1M, sendo esses valores 90,49%, 78,34%, 95,13%, 25,29%, 84,30%, 51,11% e 24,74%, respectivamente. Nos ensaios de coagulação/floculação/adsorção as eficiências máximas de remoção foram 91,41% para DQO, 90,77% para Cor, 95,31% para Turbidez, 58,36% para Cr, 98,36% para Zn, 97,58% para Cu e 99,11% para Ni. Verificou-se que após o processo combinado o efluente galvânico não apresentou as características necessárias para lançamento em corpos hídricos em função da alta concentração remanescente de Cr (1907,4 mg/L), Cor (860 PtCo/L) e DQO (330 mg/L). Verificou-se que os processos de tratamento estudados demonstraram eficiência para a maioria dos parâmetros analisados, entretanto, fazem-se necessários estudar tecnologias complementares para o tratamento deste tipo de efluente com intuito de obter um efluente dentro dos padrões de lançamentos em corpos receptores.

碩士<br>朝陽科技大學<br>環境工程與管理系碩士班<br>96<br>Electroplating industry has contributed to a lot to the economic development in Taiwan. However, agricultural land, groundwater, and agricultural crops are contaminated with the heavy metals due to the improper treatment and discharge of electroplating waster. This study aims to investigate the manufacturing process and characteristics of effluent of seven electroplating factories in central Taiwan. The influent and effluent were sampled and analyzed. The measured parameters are pH, ORP, EC, SAR and metals (Ca, Mg, K, Na, Cd, Cr, Cu, Ni, Pb, Zn, Al, Co, Fe, Mo, Si, W). Results show that pH(1factory) and Cd (5 factories) exceed the discharge standard. Compared to the irrigation standards, the effluent levels appear to exceed them with Cd (6 factories), Cr (6 factories), Ni (2 factories), Mo (4 factories), pH (1 factories), SAR (5 factories). These results indicate that the effluent, though coinciding with discharge standard, still show a higher levels than irrigation standard. SAR is found higher possibly due to the use of NaOH in the flushing of grease and oil attached in the metal surface. Compared to the irrigation standard, technical treatment and discharge standard of electroplating wastewater may need further evaluation and improvement to prevent the potential of soil, groundwater and agricultural crops contamination.

by Tsui Wai-chu.<br>Thesis (M.Phil.)--Chinese University of Hong Kong, 2000.<br>Includes bibliographical references (leaves 161-171).<br>Abstracts in English and Chinese.<br>Acknowledgements --- p.i<br>Abstract --- p.ii<br>Abbreviations --- p.vii<br>Contents --- p.ix<br>Chapter 1. --- Introduction --- p.1<br>Chapter 1.1 --- Literature review --- p.1<br>Chapter 1.1.1 --- Metal pollution in Hong Kong --- p.1<br>Chapter 1.1.2 --- Methods for removal of metal ions from industrial effluent --- p.4<br>Chapter A. --- Physico-chemical methods --- p.4<br>Chapter B. --- Biosorption --- p.7<br>Chapter 1.1.3 --- Chitin and chitosan --- p.11<br>Chapter A. --- History of chitin and chitosan --- p.11<br>Chapter B. --- Structures and sources of chitin and chitosan --- p.12<br>Chapter C. --- Characterization of chitin and chitosan --- p.17<br>Chapter D. --- Applications of chitin and chitosan --- p.19<br>Chapter 1.1.4 --- Factors affecting biosorption --- p.22<br>Chapter A. --- Solution pH --- p.22<br>Chapter B. --- Concentration of biosorbent --- p.24<br>Chapter C. --- Retention time --- p.25<br>Chapter D. --- Initial metal ion concentration --- p.26<br>Chapter E. --- Presence of other cations --- p.26<br>Chapter F. --- Presence of anions --- p.28<br>Chapter 1.1.5 --- Regeneration of metal ion-laden biosorbent --- p.28<br>Chapter 1.1.6 --- Modeling of biosorption --- p.29<br>Chapter A. --- Adsorption equilibria and adsorption isotherm --- p.29<br>Chapter B. --- Langmuir isotherm --- p.33<br>Chapter C. --- Freundlich isotherm --- p.34<br>Chapter 1.2 --- Objectives of the present study --- p.36<br>Chapter 2. --- Materials and methods --- p.37<br>Chapter 2.1 --- Biosorbents --- p.37<br>Chapter 2.1.1 --- Production of biosorbents --- p.37<br>Chapter 2.1.2 --- Pretreatment of biosorbents --- p.39<br>Chapter 2.2 --- Characterization of biosorbents --- p.39<br>Chapter 2.2.1 --- Chitin assay --- p.39<br>Chapter 2.2.2 --- Protein assay --- p.40<br>Chapter 2.2.3 --- Metal analysis --- p.41<br>Chapter 2.2.4 --- Degree of N-deacetylation analysis --- p.43<br>Chapter A. --- Diffuse reflectance Fourier transform infra-red spectroscopy --- p.43<br>Chapter B. --- Elemental analysis --- p.43<br>Chapter 2.3 --- Batch biosorption experiment --- p.44<br>Chapter 2.4 --- Selection of biosorbent for metal ion removal --- p.45<br>Chapter 2.4.1 --- Effects of pretreatments of biosorbents on adsorption of Cu --- p.45<br>Chapter A. --- Washing --- p.45<br>Chapter B. --- Pre-swelling --- p.46<br>Chapter 2.4.2 --- "Comparison of Cu2+, Ni2+ and Zn2+ removal capacities among three biosorbents" --- p.46<br>Chapter 2.4.3 --- Comparison of Cu2+ removal capacity of chitins with various degrees of N-deacetylation --- p.46<br>Chapter 2.5 --- "Effects of physico-chemical conditions on Cu2+, Ni2+ and Zn2+ adsorption by chitin A" --- p.48<br>Chapter 2.5.1 --- Solution pH and concentration of biosorbent --- p.48<br>Chapter 2.5.2 --- Retention time --- p.48<br>Chapter 2.5.3 --- Initial metal ion concentration --- p.49<br>Chapter 2.5.4 --- Presence of other cations --- p.49<br>Chapter 2.5.5 --- Presence of anions --- p.51<br>Chapter 2.6 --- Optimization of Cu2+，Ni2+ and Zn2+ removal efficiencies --- p.53<br>Chapter 2.7 --- "Recovery of Cu2+, Ni2+ and Zn2+ from metal ion-laden chitin A" --- p.53<br>Chapter 2.7.1 --- Performances of various eluents on metal ion recovery --- p.53<br>Chapter 2.7.2 --- Multiple adsorption and desorption cycle of metal ions --- p.54<br>Chapter 2.8 --- Treatment of electroplating effluent by chitin A --- p.54<br>Chapter 2.8.1 --- "Removal and recovery of Cu2+, Ni2+ and Zn2+ from electroplating effluent collected from rinsing baths" --- p.54<br>Chapter 2.8.2 --- "Removal and recovery of Cu2+, Ni2+ and Zn2+ from electroplating effluent collected from final collecting tank" --- p.55<br>Chapter 2.9 --- Data analysis --- p.56<br>Chapter 3. --- Results --- p.58<br>Chapter 3.1 --- Characterization of biosorbents --- p.58<br>Chapter 3.1.1 --- Chitin assay --- p.58<br>Chapter 3.1.2 --- Protein assay --- p.58<br>Chapter 3.1.3 --- Metal analysis --- p.58<br>Chapter 3.1.4 --- Degree of N-deacetylation analysis --- p.62<br>Chapter A. --- Diffuse reflectance Fourier transform infra-red spectroscopy --- p.62<br>Chapter B. --- Elemental analysis --- p.62<br>Chapter 3.2 --- Selection of biosorbent for metal ion removal --- p.67<br>Chapter 3.2.1 --- Effects of pretreatments of biosorbents on adsorption of Cu2+ --- p.67<br>Chapter A. --- Washing --- p.67<br>Chapter B. --- Pre-swelling --- p.67<br>Chapter 3.2.2 --- "Comparison of Cu2+, Ni2+ and Zn2+ removal capacities among three biosorbents" --- p.67<br>Chapter 3.2.3 --- Comparison of Cu2+ removal capacity of chitins with various degrees of N-deacetylation --- p.70<br>Chapter 3.3 --- "Effects of physico-chemical conditions on Cu2+, Ni2+ and Zn2+ adsorption by chitin A" --- p.70<br>Chapter 3.3.1 --- Solution pH and concentration of biosorbent --- p.70<br>Chapter 3.3.2 --- Retention time --- p.78<br>Chapter 3.3.3 --- Initial metal ion concentration --- p.80<br>Chapter 3.3.4 --- Presence of other cations --- p.93<br>Chapter 3.3.5 --- Presence of anions --- p.93<br>Chapter 3.4 --- "Optimization of Cu2+, Ni2+ and Zn2+ removal efficiencies" --- p.104<br>Chapter 3.5 --- "Recovery of Cu2+, Ni2+ and Zn2+ from metal ion-laden chitin A" --- p.104<br>Chapter 3.5.1 --- Performances of various eluents on metal ion recovery --- p.104<br>Chapter 3.5.2 --- Multiple adsorption and desorption cycle of metal ions --- p.109<br>Chapter 3.6 --- Treatment of electroplating effluent by chitin A --- p.117<br>Chapter 3.6.1 --- "Removal and recovery of Cu2+, Ni2+ and Zn2+ from electroplating effluent collected from rinsing baths" --- p.117<br>Chapter 3.6.2 --- "Removal and recovery of Cu2+, Ni2+ and Zn2+ from electroplating effluent collected from final collecting tank" --- p.121<br>Chapter 4. --- Discussion --- p.128<br>Chapter 4.1 --- Characterization of biosorbents --- p.128<br>Chapter 4.1.1 --- Chitin assay --- p.128<br>Chapter 4.1.2 --- Protein assay --- p.129<br>Chapter 4.1.3 --- Metal analysis --- p.129<br>Chapter 4.1.4 --- Degree of N-deacetylation analysis --- p.130<br>Chapter A. --- Diffuse reflectance Fourier transform infra-red spectroscopy --- p.130<br>Chapter B. --- Elemental analysis --- p.132<br>Chapter 4.2 --- Selection of biosorbent for metal ion removal --- p.133<br>Chapter 4.2.1 --- Effects of pretreatments of biosorbents on adsorption of Cu2+ --- p.133<br>Chapter A. --- Washing --- p.133<br>Chapter B. --- Pre-swelling --- p.133<br>Chapter 4.2.2 --- "Comparison of Cu2+, Ni2+ and Zn2+ removal capacities among three biosorbents" --- p.134<br>Chapter 4.2.3 --- Comparison of Cu2+ removal capacity of chitins with various degrees of N-deacetylation --- p.136<br>Chapter 4.3 --- "Effects of physico-chemical conditions on Cu2+, Ni2+ and Zn2+ adsorption by chitin A" --- p.137<br>Chapter 4.3.1 --- Solution pH and concentration of biosorbent --- p.137<br>Chapter 4.3.2 --- Retention time --- p.138<br>Chapter 4.3.3 --- Initial metal ion concentration --- p.139<br>Chapter 4.3.4 --- Presence of other cations --- p.141<br>Chapter 4.3.5 --- Presence of anions --- p.143<br>Chapter 4.4 --- "Optimization of Cu2+, Ni2+ and Zn2+ removal efficiencies" --- p.147<br>Chapter 4.5 --- "Recovery of Cu2+, Ni2+and Zn2+ from metal ion-laden chitin A" --- p.148<br>Chapter 4.5.1 --- Performances of various eluents on metal ion recovery --- p.148<br>Chapter 4.5.2 --- Multiple adsorption and desorption cycle of metal ions --- p.149<br>Chapter 4.6 --- Treatment of electroplating effluent by chitin A --- p.150<br>Chapter 4.6.1 --- "Removal and recovery of Cu2+, Ni2+ and Zn2+ from electroplating effluent collected from rinsing baths" --- p.150<br>Chapter 4.6.2 --- "Removal and recovery of Cu2+, Ni2+ and Zn2+ from electroplating effluent collected from final collecting tank" --- p.152<br>Chapter 5. --- Conclusion --- p.154<br>Chapter 6. --- Further studies --- p.156<br>Chapter 7. --- Summary --- p.158<br>Chapter 8. --- References --- p.161

by Fung King-yuen Debera.<br>On t.p., "2+" is superscript.<br>Thesis (M.Phil.)--Chinese University of Hong Kong, 1994.<br>Includes bibliographical references (leaves 102-112).<br>Acknowledgement --- p.i<br>Abstract --- p.ii<br>Table of Content --- p.iv<br>Chapter 1. --- Introduction --- p.1<br>Chapter 1.1 --- Literature review --- p.1<br>Chapter 1.1.1 --- Problems of heavy metals in the environment --- p.1<br>Chapter 1.1.2 --- Methods of removal of heavy metal from industrial effluent --- p.5<br>Chapter 1.1.3 --- The properties of magnetites --- p.10<br>Chapter 1.1.4 --- Role of magnetites in water treatment --- p.12<br>Chapter 1.1.5 --- The advantages of using magnetites and further application of magnetites --- p.16<br>Chapter 1.2 --- Objectives of the study --- p.21<br>Chapter 2. --- Materials and methods --- p.23<br>Chapter 2.1 --- Selection of the organisms --- p.23<br>Chapter 2.2 --- Culture media and chemicals --- p.23<br>Chapter 2.3 --- Growth of the bacterial cells --- p.25<br>Chapter 2.4 --- Immobilization of the bacterial cells on magnetites --- p.27<br>Chapter 2.4.1 --- Effects of chemical and physical factors on the immobilization of the bacterial cells on magnetites --- p.27<br>Chapter 2.4.2 --- Effect of pH on the desorption of cells from magnetites --- p.28<br>Chapter 2.5 --- Nickel ion uptake experiments --- p.28<br>Chapter 2.6 --- Effects of operational conditions on the nickel removal capacity of the magnetite-immobilized bacterial cells --- p.29<br>Chapter 2 .6.1 --- Effect of physical factors --- p.29<br>Chapter 2.6.2 --- Effect of chemical factors --- p.30<br>Chapter 2.7 --- Optimization of the nickel removal efficiency --- p.30<br>Chapter 2.8 --- Nickel adsorption isotherm of the magnetite- immobilized cells of Enterobacter sp4-2 --- p.30<br>Chapter 2.9 --- Recovery of adsorbed Ni2+ from the magnetite- immobilized cells of Enterobacter sp4-2 --- p.31<br>Chapter 2.9.1 --- Multiple adsorption-desorption cycles of Ni2+ by using citrate buffer --- p.32<br>Chapter 2.9.2 --- Multiple adsorption-desorption cycles of Ni2+ by using ethylenediaminetetraacetic acid (EDTA) --- p.33<br>Chapter 2.10 --- Effect of acidic treatment --- p.33<br>Chapter 2.10.1 --- Effect of acidic treatment on the nickel removal capacity of the magnetites and the magnetite- immobilized cells of Enterobacter sp4-2 --- p.33<br>Chapter 2.10.2 --- Effect of acidic treatment on the recovery of the adsorbed Ni2+ from magnetites and the magnetite- immobilized cells Enterobacter sp4-2 --- p.34<br>Chapter 2.11 --- Removal and recovery of Ni2+ from the electroplating effluent --- p.34<br>Chapter 3. --- Results --- p.36<br>Chapter 3.1 --- Effects of chemical and physical factors on the immobilization of the bacterial cells on magnetites --- p.36<br>Chapter 3.1.1 --- Effect of pH --- p.36<br>Chapter 3.1.2 --- Effect of cells to magnetites ratio --- p.36<br>Chapter 3.1.3 --- Effect of temperature --- p.39<br>Chapter 3.2 --- Effect of pH on the desorption of cells from magnetites --- p.39<br>Chapter 3.3 --- Nickel ion uptake experiments --- p.44<br>Chapter 3.4 --- Effects of operational conditions on the nickel removal capacity of the magnetite-immobilized bacterial cells --- p.44<br>Chapter 3.4.1 --- Effect of reaction temperature --- p.44<br>Chapter 3.4.2 --- Effect of retention time --- p.44<br>Chapter 3.4.3 --- Effect of pH --- p.47<br>Chapter 3.4.4 --- Effect of the presence of cations --- p.50<br>Chapter 3.4.5 --- Effect of the presence of anions --- p.50<br>Chapter 3.5 --- Optimization of the nickel removal efficiency --- p.55<br>Chapter 3.6 --- Nickel adsorption isotherm of the magnetite- immobilized cells of Enterobacter sp4-2 --- p.55<br>Chapter 3.7 --- Recovery of adsorbed Ni2+ from the magnetite- immobilized cells of Enterobacter sp4-2 --- p.59<br>Chapter 3.7.1 --- Multiple adsorption-desorption cycles of Ni2+ by using citrate buffer --- p.59<br>Chapter 3.7.2 --- Multiple adsorption-desorption cycles of Ni2+ by using ethylenediaminetetraacetic acid (EDTA) --- p.63<br>Chapter 3.8 --- Effect of acidic treatment --- p.63<br>Chapter 3.8.1 --- Effect of acidic treatment on the nickel removal capacity of the magnetites and the magnetite-immobilized cells of Enterobacter sp4-2 --- p.63<br>Chapter 3.8.2 --- Effect of acidic treatment on the recovery of the adsorbed Ni2+ from the magnetites and the magnetite-immobilized cells of Enterobacter sp4-2 --- p.66<br>Chapter 3.9 --- Removal and recovery of Ni2+ from the electroplating effluent --- p.69<br>Chapter 4. --- Discussion --- p.72<br>Chapter 4.1 --- Selection of the organisms --- p.72<br>Chapter 4.2 --- Effects of chemical and physical factors on the immobilization of the bacterial cells on magnetites --- p.72<br>Chapter 4.2.1 --- Effect of pH --- p.72<br>Chapter 4.2.2 --- Effect of cells to magnetites ratio --- p.74<br>Chapter 4.2.3 --- Effect of temperature --- p.75<br>Chapter 4.2.4 --- Effect of pH on the desorption of cells from magnetites --- p.76<br>Chapter 4.3 --- Nickel ion uptake experiments --- p.78<br>Chapter 4.4 --- Effects of operational conditions on the nickel removal capacity of the magnetite-immobilized bacterial cells --- p.80<br>Chapter 4.4.1 --- Effect of reaction temperature --- p.80<br>Chapter 4.4.2 --- Effect of retention time --- p.81<br>Chapter 4.4.3 --- Effect of pH --- p.82<br>Chapter 4.4.4 --- Effect of the presence of cations --- p.83<br>Chapter 4.4.5 --- Effect of the presence of anions --- p.84<br>Chapter 4.5 --- Optimization of the nickel removal efficiency --- p.85<br>Chapter 4.6 --- Nickel adsorption isotherm of the magnetite- immobilized cells of Enterobacter sp4-2 --- p.86<br>Chapter 4.7 --- Recovery of adsorbed Ni2+ from the magnetite- immobilized cells of Enterobacter sp4-2 --- p.87<br>Chapter 4.7.1 --- Multiple adsorption-desorption of Ni2+ --- p.89<br>Chapter 4.7.2 --- Effect of acidic treatment on the nickel removal capacity and recovery --- p.91<br>Chapter 4.8 --- Removal and recovery of Ni2+ from the electroplating effluent --- p.93<br>Chapter 5. --- Conclusion --- p.96<br>Chapter 6. --- Summary --- p.99<br>Chapter 7. --- References --- p.102

by Wong Suk Ying.<br>Thesis submitted in: November 2001.<br>Thesis (M.Phil.)--Chinese University of Hong Kong, 2002.<br>Includes bibliographical references (leaves 144-157).<br>Text in English; abstracts in English and Chinese.<br>by Wong Suk Ying.<br>Acknowledgments --- p.i<br>Abstract --- p.ii<br>Contents --- p.v<br>List of Figures --- p.x<br>List of Tables --- p.xvi<br>Chapter 1. --- INTRODUCTION --- p.1<br>Chapter 1.1 --- Electroplating Industry in Hong Kong --- p.1<br>Chapter 1.1.1 --- Typical stages in electroplating process --- p.1<br>Chapter 1.1.1.1 --- Pre-treatment --- p.1<br>Chapter 1.1.1.2 --- Electroplating --- p.3<br>Chapter 1.1.1.3 --- Post-treatment --- p.3<br>Chapter 1.1.2 --- Typical characteristics of wastestreams from electroplating industry --- p.3<br>Chapter 1.2 --- Chemical Specific Approach against Toxicity Based Approach --- p.6<br>Chapter 1.3 --- Ecotoxicological Study on Electroplating Effluent --- p.7<br>Chapter 1.4 --- Toxicity Identification Evaluation --- p.8<br>Chapter 1.4.1 --- Phase I: Toxicity Characterization --- p.9<br>Chapter 1.4.2 --- Phase II: Toxicity Identification --- p.10<br>Chapter 1.4.3 --- Phase III: Toxicity Confirmation --- p.12<br>Chapter 1.5 --- Toxicity Identification Evaluation on Electroplating Effluent --- p.14<br>Chapter 1.6 --- Selection of Organisms for Bioassays --- p.15<br>Chapter 1.6.1 --- Organism used for toxicity identification evaluation --- p.17<br>Chapter 2. --- OBJECTIVES --- p.20<br>Chapter 3. --- MATERIALS AND METHODS --- p.21<br>Chapter 3.1 --- Source of Samples --- p.21<br>Chapter 3.2 --- Toxicity Identification Evaluation: Phase I Baseline Toxicity Test --- p.21<br>Chapter 3.2.1 --- Microtox® test --- p.23<br>Chapter 3.2.2 --- Growth inhibition test of a marine unicellular microalga Chlorella pyrenoidosa CU-2 --- p.25<br>Chapter 3.2.3 --- Survival test of a marine amphipod Hylae crassicornis --- p.28<br>Chapter 3.2.4 --- Survival test of a marine shrimp juvenile Metapenaeus ensis --- p.31<br>Chapter 3.3 --- Toxicity Identification Evaluation: Phase I Toxicity Characterization --- p.34<br>Chapter 3.3.1 --- pH adjustment filtration test --- p.35<br>Chapter 3.3.2 --- Aeration test --- p.36<br>Chapter 3.3.3 --- C18 solid phase extraction test --- p.37<br>Chapter 3.3.4 --- EDTA chelation test --- p.38<br>Chapter 3.3.5 --- Graduated pH test --- p.40<br>Chapter 3.4 --- Toxicity Identification Evaluation: Phase II Toxicity Identification --- p.41<br>Chapter 3.4.1 --- Filter extraction test --- p.41<br>Chapter 3.4.2 --- Total metal content analysis --- p.42<br>Chapter 3.5 --- Toxicity Identification Evaluation: Phase III Toxicity Confirmation --- p.43<br>Chapter 3.5.1 --- Chemicals --- p.44<br>Chapter 3.5.2 --- Mass balance test --- p.44<br>Chapter 3.5.3 --- Spiking test --- p.44<br>Chapter 4. --- RESULTS --- p.46<br>Chapter 4.1 --- Chemical Characteristics of the Electroplating Effluent Samples --- p.46<br>Chapter 4.2 --- Toxicity Identification Evaluation: Phase I Baseline Toxicity --- p.46<br>Chapter 4.2.1 --- Toxicity of electroplating effluent samples on Microtox® test --- p.46<br>Chapter 4.2.2 --- Toxicity of electroplating effluent samples on growth inhibition test of microalga Chlorella pyrenoidosa CU-2 --- p.46<br>Chapter 4.2.3 --- Toxicity of electroplating effluent samples on survival test of amphipod Hyale crassicornis --- p.52<br>Chapter 4.2.4 --- Toxicity of electroplating effluent samples on survival test of shrimp juvenile Metapenaeus ensis --- p.52<br>Chapter 4.3 --- Toxicity Identification Evaluation: Phase I Toxicity Characterization --- p.52<br>Chapter 4.3.1 --- Toxicity Characterization of electroplating effluent samples using Microtox® test --- p.56<br>Chapter 4.3.2 --- Toxicity Characterization of electroplating effluent samples using microalgal growth inhibition test of Chlorella pyrenoidosa CU-2 --- p.59<br>Chapter 4.3.3 --- Toxicity Characterization of electroplating effluent samples using survival test of amphipod Hyale crassicornis --- p.65<br>Chapter 4.3.4 --- Toxicity Characterization of electroplating effluent samples using survival test of shrimp juvenile Metapenaeus ensis --- p.68<br>Chapter 4.4 --- Toxicity Identification Evaluation: Phase II Toxicity Identification --- p.73<br>Chapter 4.4.1 --- Metal analysis on the electroplating effluents --- p.75<br>Chapter 4.4.2 --- Effect of filter extraction test on toxicity recovery of the electroplating effluent samples --- p.75<br>Chapter 4.4.2.1 --- Microtox® test --- p.75<br>Chapter 4.4.2.2 --- Growth inhibition test of microalga Chlorella pyrenoidosa CU-2 --- p.75<br>Chapter 4.4.2.3 --- Survival test of amphipod Hyale crassicornis --- p.81<br>Chapter 4.4.2.4 --- Survival test of shrimp juvenile Metapenaeus ensis --- p.90<br>Chapter 4.4.3 --- Effect of filter extraction test on metal ions recovery of the electroplating effluent samples --- p.90<br>Chapter 4.5 --- Toxicity Identification Evaluation: Phase III Toxicity Confirmation --- p.96<br>Chapter 4.5.1 --- Mass balance test results on Microtox® test --- p.96<br>Chapter 4.5.2 --- Mass balance test results on survival test of amphipod Hyale crassicornis --- p.104<br>Chapter 4.5.3 --- Spiking test results on Microtox® test --- p.106<br>Chapter 4.5.4 --- Spiking test results on survival test of amphipod Hyale crassicornis --- p.113<br>Chapter 5. --- DISCUSSION --- p.118<br>Chapter 5.1 --- Toxicity Identification Evaluation: Phase I Baseline Toxicity --- p.118<br>Chapter 5.2 --- Toxicity Identification Evaluation: Phase I Toxicity Characterization --- p.119<br>Chapter 5.2.1 --- pH adjustment filtration test --- p.119<br>Chapter 5.2.2 --- Aeration test --- p.120<br>Chapter 5.2.3 --- C18 solid phase extraction test --- p.120<br>Chapter 5.2.4 --- EDTA chelation test --- p.120<br>Chapter 5.2.5 --- Graduated pH test --- p.121<br>Chapter 5.3 --- Toxicity Identification Evaluation: Phase II Toxicity Identification --- p.122<br>Chapter 5.3.1 --- Metal analysis on the electroplating effluents --- p.122<br>Chapter 5.3.2 --- Effect of filter extraction test on toxicity and metal ions recovery of the electroplating effluent samples --- p.123<br>Chapter 5.3.3 --- Comparison between the concentrations of the metal ions in the electroplating effluent samples with the Technical Memorandum on standards for effluent discharged --- p.124<br>Chapter 5.3.4 --- Comparison between the concentrations of the metal ions in the electroplating effluent samples with the toxicity of the metal ions reported in the literature --- p.124<br>Chapter 5.3.4.1 --- Microtox® test --- p.126<br>Chapter 5.3.4.2 --- Microalga --- p.126<br>Chapter 5.3.4.3 --- Amphipod --- p.126<br>Chapter 5.3.4.4 --- Shrimp --- p.126<br>Chapter 5.4 --- Toxicity Identification Evaluation: Phase III Toxicity Confirmation --- p.131<br>Chapter 5.4.1 --- Mass balance test on Microtox® test --- p.132<br>Chapter 5.4.2 --- Mass balance test on survival test of amphipod Hyale crassicornis --- p.133<br>Chapter 5.4.3 --- Spiking test on Microtox® test --- p.133<br>Chapter 5.4.4 --- Spiking test on survival test of amphipod Hyale crassicornis --- p.134<br>Chapter 5.5 --- Toxicity of the Metal Ions Identified as the Toxicants in the Electroplating Effluent --- p.135<br>Chapter 5.5.1 --- Copper --- p.135<br>Chapter 5.5.2 --- Nickel --- p.137<br>Chapter 5.5.3 --- Zinc --- p.138<br>Chapter 5.6 --- Summary --- p.140<br>Chapter 6. --- CONCLUSIONS --- p.142<br>Chapter 7. --- REFERENCES --- p.144<br>Chapter 7.1 --- APPENDIXES --- p.158

by Sze Kwok Fung Calvin.<br>Thesis (M.Phil.)--Chinese University of Hong Kong, 1996.<br>Includes bibliographical references (leaves 118-130).<br>Acknowledgement --- p.i<br>Abstract --- p.ii<br>Content --- p.iv<br>Chapter 1. --- Introduction --- p.1<br>Chapter 1.1 --- Literature review --- p.1<br>Chapter 1.1.1 --- Heavy metals in the environment --- p.1<br>Chapter 1.1.2 --- Heavy metal pollution in Hong Kong --- p.2<br>Chapter 1.1.3 --- Electroplating industry in Hong Kong --- p.6<br>Chapter 1.1.4 --- Chemistry and toxicity of copper in the environment --- p.7<br>Chapter 1.1.5 --- Methods of removal of heavy metal from industrial effluent --- p.9<br>Chapter A. --- Physico-chemical methods --- p.9<br>Chapter B. --- Biological methods --- p.9<br>Chapter 1.1.6 --- Methods of recovery of heavy metal from metal-loaded biosorbent --- p.17<br>Chapter 1.1.7 --- The physico-chemical properties of magnetites --- p.18<br>Chapter 1.1.8 --- Magnetites for water and wastewater treatment --- p.19<br>Chapter 1.1.9 --- Immobilized cell technology --- p.24<br>Chapter 1.1.10 --- Stirrer-tank bioreactor --- p.26<br>Chapter 1.2 --- Objectives of the present study --- p.28<br>Chapter 2. --- Materials and Methods --- p.30<br>Chapter 2.1 --- Selection of copper-resistant bacteria --- p.30<br>Chapter 2.2 --- Culture media and chemicals --- p.30<br>Chapter 2.3 --- Growth of the bacterial cells --- p.32<br>Chapter 2.4 --- Immobilization of the bacterial cells on magnetites --- p.32<br>Chapter 2.4.1 --- Effects of physical and chemical factors on the immobilization of the bacterial cells on magnetites --- p.34<br>Chapter 2.4.2 --- Effects of pH on the desorption of bacterial cells from magnetites --- p.34<br>Chapter 2.5 --- Copper ion uptake experiments --- p.35<br>Chapter 2.6 --- Effects of physico-chemical and operational factors on the Cu2+ removal capacity of the magnetite-immobilized bacterial cells --- p.35<br>Chapter 2.7 --- Transmission electron micrograph and scanning electron micrograph of Pseudomonas putida 5-X loaded with Cu2+ --- p.36<br>Chapter 2.7.1 --- Transmission electron micrograph --- p.36<br>Chapter 2.7.2 --- Scanning electron micrograph --- p.37<br>Chapter 2.8 --- Copper ion adsorption isotherm of the magnetite-immobilized cells of Pseudomonas putida 5-X --- p.37<br>Chapter 2.9 --- Recovery of adsorbed Cu2+ from the magnetite-immobilized cells of Pseudomonas putida 5-X --- p.38<br>Chapter 2.9.1 --- Effects of eluents on the Cu2+ removal and recovery capacity of the magnetite-immobilized cells --- p.38<br>Chapter 2.9.2 --- Batch type multiple adsorption-desorption cycles of Cu2+ using ethylenediaminetetra-acetic acid (EDTA) --- p.39<br>Chapter 2.10 --- Removal and recovery of Cu2+ from the electroplating effluent by a bioreactor --- p.39<br>Chapter 2.10.1 --- Batch type multiple adsorption-desorption cycles using the copper solution and electroplating effluent --- p.39<br>Chapter 2.10.2 --- Continuous type bioreactor to remove and recover Cu2+ from copper solution and electroplating effluent --- p.40<br>Chapter 2.11 --- Statistical analysis of data --- p.43<br>Chapter 3. --- Results --- p.44<br>Chapter 3.1 --- Effects of physical and chemical factors on the immobilization of the bacterial cells on magnetites --- p.44<br>Chapter 3.1.1 --- Effects of cells to magnetites ratio --- p.44<br>Chapter 3.1.2 --- Effects of pH --- p.44<br>Chapter 3.1.3 --- Effects of temperature --- p.44<br>Chapter 3.2 --- Effects of pH on the desorption of bacterial cells from magnetites --- p.49<br>Chapter 3.3 --- Copper ion uptake experiments --- p.49<br>Chapter 3.4 --- Effects of physico-chemical and operational factors on the Cu2+ removal capacity of the magnetite-immobilized bacterial cells --- p.49<br>Chapter 3.4.1 --- Effects of pH --- p.49<br>Chapter 3.4.2 --- Effects of temperature --- p.53<br>Chapter 3.4.3 --- Effects of retention time --- p.53<br>Chapter 3.4.4 --- Effects of cations --- p.53<br>Chapter 3.4.5 --- Effects of anions --- p.57<br>Chapter 3.5 --- Transmission electron micrograph of Pseudomonas putida 5-X loaded with Cu2+ --- p.62<br>Chapter 3.6 --- Scanning electron micrograph of Pseudomonas putida 5-X loaded with Cu2+ --- p.62<br>Chapter 3.7 --- Copper ion adsorption isotherm of the magnetite-immobilized cells of Pseudomonas putida 5-X --- p.68<br>Chapter 3.8 --- Recovery of adsorbed Cu2+ from the magnetite-immobilized cells of Pseudomonas putida 5-X --- p.68<br>Chapter 3.8.1 --- Effects of eluents on the Cu2+ removal and recovery capacity of the magnetite-immobilized cells --- p.68<br>Chapter 3.8.2 --- Batch type multiple adsorption-desorption cycles of Cu2+ using ethylenediaminetetra-acetic acid (EDTA) --- p.74<br>Chapter 3.9 --- Removal and recovery of Cu2+ from the electroplating effluent by a bioreactor --- p.74<br>Chapter 3.9.1 --- Batch type multiple adsorption-desorption cycles using the copper solution and electroplating effluent --- p.74<br>Chapter 3.9.2 --- Continuous type bioreactor to remove and recover Cu2+ from copper solution and electroplating effluent --- p.81<br>Chapter 4. --- Discussion --- p.89<br>Chapter 4.1 --- Selection of copper-resistant bacteria --- p.89<br>Chapter 4.2 --- Effects of physical and chemical factors on the immobilization of the bacterial cells on magnetites --- p.89<br>Chapter 4.2.1 --- Effects of cells to magnetites ratio --- p.89<br>Chapter 4.2.2 --- Effects of pH --- p.90<br>Chapter 4.2.3 --- Effects of temperature --- p.91<br>Chapter 4.2.4 --- Effects of pH on the desorption of bacterial cells from magnetites --- p.92<br>Chapter 4.3 --- Copper ion uptake experiments --- p.93<br>Chapter 4.4 --- Effects of physico-chemical and operational factors on the Cu2+ removal capacity of the magnetite-immobilized bacterial cells --- p.94<br>Chapter 4.4.1 --- Effects of pH --- p.95<br>Chapter 4.4.2 --- Effects of temperature --- p.96<br>Chapter 4.4.3 --- Effects of retention time --- p.97<br>Chapter 4.4.4 --- Effects of cations --- p.98<br>Chapter 4.4.5 --- Effects of anions --- p.101<br>Chapter 4.5 --- Transmission electron micrograph of Pseudomonas putida 5-X loaded with Cu2+ --- p.101<br>Chapter 4.6 --- Scanning electron micrograph of Pseudomonas putida 5-X loaded with Cu2+ --- p.102<br>Chapter 4.7 --- Copper ion adsorption isotherm of the magnetite-immobilized cells of Pseudomonas putida 5-X --- p.103<br>Chapter 4.8 --- Recovery of adsorbed Cu2+ from the magnetite-immobilized cells of Pseudomonas putida 5-X --- p.104<br>Chapter 4.8.1 --- Effects of eluents on the Cu2+ removal and recovery capacity of the magnetite-immobilized cells --- p.104<br>Chapter 4.8.2 --- Batch type multiple adsorption-desorption cycles of Cu2+ using ethylenediaminetetra-acetic acid (EDTA) --- p.105<br>Chapter 4.9 --- Removal and recovery of Cu2+ from the electroplating effluent by a bioreactor --- p.107<br>Chapter 4.9.1 --- Batch type multiple adsorption-desorption cycles using the copper solution and electroplating effluent --- p.107<br>Chapter 4.9.2 --- Continuous type bioreactor to remove and recover Cu2+ from copper solution and electroplating effluent --- p.108<br>Chapter 5. --- Conclusion --- p.110<br>Chapter 6. --- Summary --- p.112<br>Chapter 7. --- References --- p.115