Esta pesquisa propôs o desenvolvimento de um sistema de biofiltros submersos, modificados com base na configuração de filtros de pedra, visando o pós-tratamento do efluente de lagoas de estabilização, inicialmente para a remoção de algas. A modificação consiste na variação das alturas da camada filtrante e na colocação de tampa na superfície do BS, evitando o acesso da luz. O esgoto tratado captado na lagoa de maturação foi feito em duas profundidades – a 60 cm de profundidade da superfície da lagoa (denominada zona superficial) e a 180 cm de profundidade da superfície da lagoa (denominada zona intermediárias). O experimento foi composto por 8 BS sendo 4 BS alimentados pelo esgoto captado na zona superficial (60 cm) e outros 4 BS alimentados pela esgoto captado na zona intermediária (180 cm). Foi utilizado, como recheio dos biofiltros submersos, pedra brita nº 3, nas seguintes alturas de camada filtrante: 50 cm, 100 cm, 150 cm e 200 cm, tendo por objetivo avaliar a influência deste fator sobre a eficiência de remoção de algas mediante análise de Clorofila a, e outras 16 variáveis de qualidade associadas neste estudo. Concluiu-se que a extração a partir da zona superficial da lagoa de maturação, e uma profundidade de leito entre 150 cm e 200 cm, foram os parâmetros operacionais que levaram a um melhor desempenho global dos biofiltros submersos modificados, e mais especificamente quanto às seguintes variáveis: Clorofila a, DQO (Demanda Química de Oxigênio), DBO (Demanda Bioquímica de Oxigênio) e sólidos totais. / This research proposed the development of a submerged bio filters system, modified based in rock filters configuration, aiming the post treatment of the effluent of stabilization lagoons, for algae removal first. The modification consists invariance of the heights of the filter layer and the cover placed on the surface of the BS, preventing access of light. The treated sewage captured in the maturation lagoon was made at two depths – at 60cm depth of the lagoon surface (called superficial zone) and at 180cm depth of the lagoon surface (called intermediary zone). The experiment consisted of 8 BS, with 4 BS being fed by sewage captured in the superficial zone (60 cm) and other 4 BS fed by sewage captured in the intermediary zone (180 cm). It was used, as a stuff of submerged biofilters, rock number three, at the following heights of filtering layers: 50 cm, 100 cm, 150 cm e 200 cm, aiming to evaluate the influence of this factor over algae removal efficiency towards chlorophyll a, and other 16 quality variables associated in this study. It was concluded that the collecting from superficial zone of the maturation lagoon, and a layer depth between 150 cm e 200 cm, were the operational parameters that lead to a better overall performance of modified submerged biofilters, and more particularly to the following variables: Chlorophyll a, COD (Chemical Oxygen Demand), BOD (Biochemical Oxygen Demand) and total solids.

Esta pesquisa propõe a análise das práticas políticas que se conformam em torno da problemática que relaciona habitação irregular precária e preservação dos recursos hídricos em São Paulo, a saber, as remoções e os processos de reurbanização/regularização. As práticas são analisadas a partir de pesquisa etnográfica realizada no distrito do Grajaú, região sul da cidade, marcado pelo alto crescimento populacional irregular em áreas de mananciais. Em uma abordagem que se afasta daquelas de avaliação de políticas, busca-se compreender as formas pelas quais a gestão dessas áreas produz e lida com situações que chamo de ingovernáveis. / This research proposes an analysis of political practices on the problem that relates irregular and precarious housing problem and preservation of water resources in São Paulo, namely the removal and the processes of reurbanization / regularization. The practices are analyzed from an ethnographic study in Grajaú, south region of São Paulo, marked by high and irregular population growth in watershed areas. In an approach that takes distance from those of policy evaluation, this work seeks to understand the ways in which the management of these areas produces and deals with situations that are called ungovernable.

O objetivo deste estudo foi avaliar a alteração de temperatura durante preparo cavitário em dentina cariada e hígida e a eficiência na remoção de tecido cariado com Er:YAG. Foram utilizados 30 terceiros molares humanos hígidos, doados pelo Banco de Dentes da FORP-USP, os quais tiveram suas raízes removidas e as coroas seccionadas, obtendo-se 60 fragmentos de 2,5mm de espessura. Os espécimes foram divididos em 2 grupos (n=30): dentina cariada e dentina hígida (controle) e em 3 subgrupos (n=10), de acordo com as freqüências de laser aplicadas (4, 6 e 10Hz). Foi empregada energia constante de 200mJ no modo não-contato, focado e sob refrigeração. A indução das lesões artificiais de cárie foi realizada pelo modelo bacteriano, no qual foram utilizadas cepas de Streptococcus mutans. O registro da temperatura foi realizado antes do inicio da irradiação, após 10 segundos e ao final do preparo. Após este procedimento, os fragmentos foram analisados por DIAGNOdent® e microscopia óptica de luz, utilizando-se o software Axio Vision 4.3 LE, para quantificar a remoção de dentina cariada. Para a análise morfológica, 5 espécimes de cada grupo foram aleatoriamente selecionados e preparados para microscopia eletrônica de varredura. Os dados foram submetidos à Análise de Variância α=5% e, quando apropriado, ao teste de Fisher. Os resultados mostraram que todas as freqüências do laser Er:YAG promoveram aumento gradual e significante da temperatura durante o preparo cavitário, independente do substrato. Com relação às freqüências de laser empregadas, observou-se que apenas a de 10Hz promoveu aumento diferencial de temperatura, sendo observado neste subgrupo o maior acúmulo de calor, em ambos os substratos. A análise por Diagnodent® revelou que a remoção de tecido cariado foi semelhante entre os subgrupos de 4 e 6Hz, e maior no de 10Hz. Contudo, por microscopia óptica de luz, os subgrupos de 6 e 10Hz foram estatisticamente iguais e o de 4Hz apresentou os menores valores de remoção de tecido cariado. A avaliação morfológica da superfície e subsuperfície dos espécimes revelou a presença de tecido dentinário desmineralizado em todos os subgrupos estudados. Contudo, em preparos realizados com 4Hz, foi observado que a dentina cariada remanescente apresentava sua estrutura colágena desnaturada. Assim, conclui-se que o aumento da freqüência do laser Er:YAG promove aumento gradativo e significante da temperatura em função do tempo, independentemente do substrato, não atingindo níveis nocivos ao tecido pulpar e uma ablação mais eficiente do tecido dentinário cariado e que a irradiação do tecido dentinário cariado resulta em uma superfície mais uniforme em relação ao tecido dentinário hígido. / The aim of this study was to evaluate the thermal alterations during cavity preparation with sound and caries dentin and dentin caries removal efficiency using Er:YAG laser. Thirty humans molars, donated by FORP-USP Teeth Bank, had the root removed and the crown sectioned getting sixty fragments with 2.5-mm thick. The fragments were assigned into two groups (n=30): artificial dentin caries and sound dentin (control group) and 3 subgroups (n=10), according to the irradiation frequency used (4, 6, or 10Hz) at a constant energy level of 200mJ, focused-mode and under refrigeration. The artificial caries lesion was obtained by the bacterial model with was used Streptococcus mutans. Before irradiation, a thermocouple, adapted to the tooth fragment, recorded the initial temperature value (°C); then, the temperature was measured at every 10s during irradiation and after finishing irradiation. A caries detection system (DIAGNOdentTM) and a light microscopy software (Axion VisionTM) was employed to evaluate the demineralized dentin removal. The morphologic analyses used 5 fragments randomly selected from each group and processed for the accomplishment scanning electron microscope. Data were analyzed by ANOVA and Fishers tests (α=5%). The results revealed that the temperature increased gradually over time for all groups, independent the type of substrate. Concerning the frequencies it was observed that irradiation with 10Hz promoted the highest temperature values for both substrates and it was statistical different of remaining frequencies. The caries detection system revealed that the caries removal was similar with 4 and 6Hz, and was superior with 10Hz. However with the light microscopy software the frequency the caries removal was similar with 6 and 10Hz and the frequency of 4Hz presented the lowest caries removal values. The surface and subsurface morphologic analyses revealed the presence of demineralized dentin in all frequencies studied. However in the preparation carried through with 4Hz, the remaining dentine beyond demineralized, presented its collagen structure disorganized. It can be concluded by the present study that the Er:YAG laser frequency increase provides a higher temperature increase for sound and caries dentin, however without reaching harmful levels to the dental pulp, as well a greater caries dentin removal and the caries dentin irradiation provides a regular surface compared with sound dentin.

Nessa pesquisa são relatados os resultados da determinação das concentrações de microcistina e de biomassa algal após as várias etapas de tratamento de amostras de água coletadas junto ao reservatório de Barra Bonita-SP visando obtenção de água potável. O tratamento foi realizado em escala de laboratório com e sem aplicação de carvão ativado em pó (CAP) e as etapas foram: coagulação com aplicação de cloreto férrico, sedimentação, filtração em papel de filtro. Foi possível observar que a pré-clarificação desse tipo de água por coagulação seguida de sedimentação requereu dosagens relativamente elevadas de cloreto férrico (80 mg/L), tendo sido verificada eficiência muito baixa de remoção de microcistina nas etapas de tratamento por sedimentação seguida de filtração, quando não foi aplicado CAP. Apenas com a aplicação de CAP a microcistina foi reduzida à níveis que atendessem os padrões de potabilidade previstos na Portaria 518/04 (concentração menor que 1 &#956g/L). A determinação de microcistina pelo método que utiliza Imunoadsorventes Ligados à Enzima (ELISA) mostrou-se uma ferramenta útil e confiável para detectar e quantificar essa toxina, embora ainda apresente custo relativamente elevado. / This report presents the results of the quantification of microcystins and algae biomass concentrations after treatment of water samples taken from the Barra Bonita reservoir, for production of potable water. Bench-scale tests were carried out with and without powdered activated carbon (PAC) and the treatment processes used were: coagulation with ferric chloride (FeCl3), sedimentation and filtration with paper filter. It was determined that pre-clarification followed by sedimentation required substantial dosages of ferric chloride (80 mg/L). The removal of microcystins using sedimentation followed by filtration was ineffective without PAC. The use of PAC is required to produce water that meets current potability standards for microcystins removal as specified in Decree 518/04 (concentration less than 1 &#956g/L). Analysis of microcystins using the Enzime-Linked Immunosorbent Assay Method (ELISA) has proven to be an effective and reliable procedure to detect and quantify this toxin, although relatively expensive.

by So Chi Ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1991. / Includes bibliographical references. / Acknowledgement --- p.i / Abstract --- p.ii / Chapter 1. --- Objectives of the Study --- p.1 / Chapter 2. --- Literature Review --- p.2 / Chapter 2.1 --- Heavy Metals in the Environment --- p.2 / Chapter 2.2 --- Heavy Metal Pollution in Hong Kong --- p.3 / Chapter 2.3 --- Chemistry and Toxicity of Copper in the Environment --- p.6 / Chapter 2.4 --- Conventional and Alternative Methods for Heavy Metal Removal --- p.10 / Chapter 2.5 --- Heavy Metal Removal by Microorganisms --- p.14 / Chapter 2.6 --- Factors Affecting Biosorption of Heavy Metals --- p.27 / Chapter 2.7 --- Applicability of Biosorbent in Heavy Metal Removal --- p.31 / Chapter 3. --- Materials and Methods --- p.36 / Chapter 3.1 --- Screening of Bacteria for Copper Removal Capacity --- p.36 / Chapter 3.1.1 --- Isolation of Bacteria from Activated Sludge --- p.36 / Chapter 3.1.2 --- Selection of Copper Resistant Bacteria from Water Samples --- p.37 / Chapter 3.1.3 --- Pre-screening of Bacteria for Copper Uptake --- p.37 / Chapter 3.1.4 --- Determination of Copper Removal Capacity of Selected Bacteria --- p.37 / Chapter 3.2 --- Effect of Culture Conditions on Copper Removal Capacity of Pseudomonas putida 5-X --- p.39 / Chapter 3.2.1 --- Effect of Nutrient Limitation --- p.39 / Chapter 3.2.2 --- Effect of Incubation Temperature and Culture Age --- p.41 / Chapter 3.3 --- Determination of Copper Uptake Mechanism of Pseudomonas putida 5-X --- p.41 / Chapter 3.3.1 --- Effect of Glucose and Sodium Azide on Copper Removal Capacity --- p.41 / Chapter 3.3.2 --- Transmission Electron Micrograph of Pseudomonas putida 5-X after Copper Uptake --- p.43 / Chapter 3.4 --- Effect of Pretreatment of Cells on Copper Removal Capacity of Pseudomonas putida 5-X --- p.43 / Chapter 3.5 --- Physico-chemical Characterization of Pseudomonas putida 5-X as Biosorbent for Copper Removal --- p.43 / Chapter 3.5.1 --- Determination of Copper Uptake Kinetics --- p.43 / Chapter 3.5.2 --- Determination of Freundlich Isotherm for Copper Uptake --- p.44 / Chapter 3.5.3 --- Effect of pH on Copper Removal Capacity --- p.44 / Chapter 3.5.4 --- Effect of Metal Ions on Copper Removal Capacity --- p.44 / Chapter 3.5.5 --- Effect of Anions on Copper Removal Capacity --- p.45 / Chapter 3.6 --- Copper Removal by Immobilized Cells of Pseudomonas putida 5-X --- p.45 / Chapter 3.6.1 --- Effect of Retention Time on Copper Removal Capacity of Immobilized Cells --- p.47 / Chapter 3.6.2 --- Efficiency of Copper Recovery from Immobilized Cells by Various Eluants --- p.47 / Chapter 3.6.3 --- Performance of Immobilized Cells on Multiple Copper Loading-elution Cycles --- p.48 / Chapter 3.6.4 --- Treatments of Effluent from an Electroplating Factory by Immobilized Cells --- p.48 / Chapter 4. --- Results --- p.49 / Chapter 4.1 --- Screening of Bacteria for Copper Removal Capacity --- p.49 / Chapter 4.2 --- Effect of Culture Conditions on Copper Removal Capacity of Pseudomonas putida 5-X --- p.49 / Chapter 4.2.1 --- Effect of Nutrient Limitation --- p.49 / Chapter 4.2.2 --- Effect of Incubation Temperature and Culture Age --- p.52 / Chapter 4.3 --- Determination of Copper Uptake Mechanism of Pseudomonas putida 5-X --- p.52 / Chapter 4.3.1 --- Effect of Glucose and Sodium Azide on Copper Removal Capacity --- p.52 / Chapter 4.3.2 --- Transmission Electron Micrograph of Pseudomonas putida 5-X after Copper Uptake --- p.52 / Chapter 4.4 --- Effect of Pretreatment of Cells on Copper Removal Capacity of Pseudomonas putida 5-X --- p.56 / Chapter 4.5 --- Physico-chemical Characterization of Pseudomonas putida 5-X as Biosorbent for Copper Removal --- p.56 / Chapter 4.5.1. --- Determination of Copper Uptake Kinetics --- p.56 / Chapter 4.5.2 --- Determination of Freundlich Isotherm for Copper Uptake --- p.56 / Chapter 4.5.3 --- Effect of pH on Copper Removal Capacity --- p.60 / Chapter 4.5.4 --- Effect of Metal Ions on Copper Removal Capacity --- p.60 / Chapter 4.5.5 --- Effect of Anions on Copper Removal Capacity --- p.60 / Chapter 4.6 --- Copper Removal by Immobilized Cells of Pseudomonas putida 5-X --- p.60 / Chapter 4.6.1 --- Copper Removal Capacity of Immobilized Cells and Breakthrough Curve for Copper Removal --- p.60 / Chapter 4.6.2 --- Effect of Retention Time on Copper Removal Capacity of Immobilized Cells --- p.65 / Chapter 4.6.3 --- Efficiency of Copper Recovery from Immobilized Cells by Various Eluants --- p.65 / Chapter 4.6.4 --- Performance of Immobilized Cells on Multiple Copper Loading-elution Cycles --- p.65 / Chapter 4.6.5 --- Treatment of Effluent from an Electroplating Factory by Immobilized Cells --- p.65 / Chapter 5. --- Discussion --- p.72 / Chapter 5.1 --- Screening of Bacteria for Copper Removal Capacity --- p.72 / Chapter 5.2 --- Effect of Culture Conditions on Copper Removal Capacity of Pseudomonas putida 5-X --- p.73 / Chapter 5.2.1 --- Effect of Nutrient Limitation --- p.73 / Chapter 5.2.2 --- Effect of Incubation Temperature and Culture Age --- p.74 / Chapter 5.3 --- Determination of Copper Uptake Mechanism of Pseudomonas putida 5-X --- p.75 / Chapter 5.3.1 --- Effect of Glucose and Sodium Azide on Copper Removal Capacity --- p.75 / Chapter 5.3.2 --- Transmission Electron Micrograph of Pseudomonas putida 5-X after Copper Uptake --- p.75 / Chapter 5.4 --- Effect of Pretreatment of Cells on Copper Removal Capacity of Pseudomonas putida 5-X --- p.76 / Chapter 5.5 --- Physico-chemical Characterization of Pseudomonas putida 5-X as Biosorbent for Copper Removal --- p.77 / Chapter 5.5.1 --- Copper Uptake Kinetics --- p.77 / Chapter 5.5.2 --- Freundlich Isotherm for Copper Uptake --- p.78 / Chapter 5.5.3 --- Effect of pH on Copper Removal Capacity --- p.78 / Chapter 5.5.4 --- Effect of Metal Ions on Copper Removal Capacity --- p.79 / Chapter 5.5.5 --- Effect of Anions on Copper Removal Capacity --- p.80 / Chapter 5.6 --- Copper Removal by Immobilized Cells of Pseudomonas putida 5-X --- p.80 / Chapter 5.6.1 --- Copper Removal Capacity of Immobilized Cells and Breakthrough Curve for Copper Removal --- p.80 / Chapter 5.6.2 --- Effect of Retention Time on Copper Removal Capacity of Immobilized Cells --- p.82 / Chapter 5.6.3 --- Efficiency of Copper Recovery from Immobilized Cells by Various Eluants --- p.82 / Chapter 5.6.4 --- Performance of Immobilized Cells on Multiple Copper Loading-elution Cycles 的 --- p.83 / Chapter 5.6.5 --- Treatment of Effluent from an Electroplating Factory by Immobilized Cells --- p.84 / Chapter 6. --- Conclusion --- p.85 / Chapter 7. --- Summary --- p.87 / Chapter 8. --- References --- p.89

by Stephen, Man-yuen Cheng. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 124-141). / Abstract also in Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / List of Figures --- p.iv / List of Tables --- p.ix / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- The development of dyes --- p.1 / Chapter 1.2 --- The chemistry of azo dyes --- p.2 / Chapter 1.3 --- "Evaluation of dyes submitted under the ""Toxic Substances Control Act"" new chemicals programme" --- p.6 / Chapter 1.4 --- Environmental concerns of dyes --- p.7 / Chapter 1.5 --- Decolorization techniques --- p.11 / Chapter 1.5.1 --- Activated sludge process --- p.11 / Chapter 1.5.2 --- Chlorination --- p.12 / Chapter 1.5.3 --- Fenton's reaction --- p.13 / Chapter 1.5.4 --- Ozonation --- p.13 / Chapter 1.5.5 --- Adsorption by activated carbon --- p.13 / Chapter 1.5.6 --- Chemical flocculation --- p.14 / Chapter 1.5.7 --- Coagulation --- p.14 / Chapter 1.5.8 --- Advance Oxidation Process --- p.15 / Chapter 1.5.8a --- Photocatalytic activation --- p.17 / Chapter 1.5.8b --- Enhancement of reaction rates of photocatalytic reaction --- p.21 / Chapter 1.5.9 --- Biosorption of azo dyes by Pseudomonas sp. K-l --- p.23 / Chapter 1.6 --- Water pollution in Hong Kong --- p.24 / Chapter 1.7 --- Purpose of study --- p.24 / Chapter 2 --- Objectives --- p.27 / Chapter 3 --- Materials and Methods --- p.28 / Chapter 3.1 --- Materials --- p.28 / Chapter 3.1.1 --- Azo dyes --- p.28 / Chapter 3.1.2 --- Biosorbent --- p.28 / Chapter 3.1.3 --- Chemicals --- p.28 / Chapter 3.2 --- Photocatalytic reactor --- p.31 / Chapter 3.3 --- Determination of the peak absorbance of five azo dyes at different pH --- p.31 / Chapter 3.4 --- Determination of dye concentration by measuring at peak absorbance --- p.37 / Chapter 3.5 --- Determination of pseudo-first-order rate constant --- p.37 / Chapter 3.6 --- Effect of initial concentration of procion red MX-5B on photocatalytic degradation --- p.39 / Chapter 3.7 --- Effect of initial concentration of hydrogen peroxide on photocatalytic degradation of procion red MX-5B --- p.40 / Chapter 3.8 --- Effect of initial pH on the photocatalytic degradation of procion red MX-5B --- p.40 / Chapter 3.9 --- Effect of initial temperature on the photocatalytic degradation of procion red MX-5B --- p.40 / Chapter 3.10 --- Effect of titanium dioxide on the photocatalytic degradation of procion red MX-5B --- p.40 / Chapter 3.11 --- Effect of UV intensity in the photocatalytic degradation of procion red MX-5B --- p.41 / Chapter 3.12 --- Degradation kinetics of different dyes --- p.41 / Chapter 3.13 --- Degradation of 40 mg/L of procion red MX-5B under optimized conditions --- p.41 / Chapter 3.14 --- "Degradation of 1,000 mg/L of procion red MX-5B under optimized conditions" --- p.42 / Chapter 3.15 --- Temporal change of the concentration of procion red MX-5B in calcium alginate beads --- p.42 / Chapter 3.16 --- "Temporal change of the concentration of procion red MX-5B in alginate beads of 5,000 mg/L of Ti02" --- p.43 / Chapter 3.17 --- "Temporal change of the concentration of procion red MX-5B in alginate beads of 10,000 mg/L of Ti02" --- p.43 / Chapter 3.18 --- Effect of the concentration of titanium dioxide in alginate beads in the photocatalytic degradation of procion red MX-5B --- p.45 / Chapter 3.19 --- "Effect of hydrogen peroxide in the photocatalytic degradation of procion red MX-5B in 5,000 mg/L of Ti02-alginate beads" --- p.47 / Chapter 3.20 --- "Temporal change of the concentration of procion red MX-5B in alginate beads with 5,000 mg/L of Ti02" --- p.47 / Chapter 3.21 --- "Effect of biomass of Pseudomonas sp. K1 on the photocatalytic degradation of procion red MX-5B in alginate beads with 5,000 mg/L of Ti02" --- p.48 / Chapter 3.22 --- Diffuse reflectance-IR spectroscopic analysis of degradation product(s) --- p.49 / Chapter 3.23 --- Nuclear magnetic resonance (NMR) spectroscopic analysis of degradation products --- p.49 / Chapter 3.24 --- Toxicological evaluation of degradation products using Microtox® test --- p.51 / Chapter 4 --- Result --- p.54 / Chapter 4.1 --- Biosorption of dyes by Pseudomonas sp. K1 --- p.54 / Chapter 4.2 --- UV intensities of the eight Cole-Parmer UV lamps at 365 nm --- p.54 / Chapter 4.3 --- Determination of the peak absorbance of five azo dyes at different pH using scanning spectrophotometer --- p.54 / Chapter 4.4 --- Determination of dye concentration by measuring at peak absorbance --- p.66 / Chapter 4.5 --- Effect of initial concentration of procion red MX-5Bin photocatalytic degradation rate --- p.66 / Chapter 4.6 --- Effect of initial concentration of hydrogen peroxide on the photocatalytic degradation of procion red MX-5B --- p.73 / Chapter 4.7 --- Effect of initial pH on photocatalytic degradation of procion red MX-5B --- p.73 / Chapter 4.8 --- Effect of initial temperature on photocatalytic degradation of procion red MX-5B --- p.73 / Chapter 4.9 --- Effect of titanium dioxide on photocatalytic degradation of procion red MX-5B --- p.77 / Chapter 4.10 --- Effect of UV intensity on photocatalytic degradation of procion red MX-5B --- p.77 / Chapter 4.11 --- Photocatalytic degradation kinetics of different azo dyes --- p.77 / Chapter 4.12 --- Photocatalytic degradation of 40 mg/L of reactive red241 under optimized conditions --- p.77 / Chapter 4.13 --- Photocatalytic degradation of 40 mg/L procion red MX-5B under optimized conditions --- p.81 / Chapter 4.14 --- "Photocatalytic degradation of 1,000 mg/L of procion red MX-5B under optimized conditions" --- p.81 / Chapter 4.15 --- Temporal change of the concentration of procion red MX-5B in calcium alginate beads --- p.81 / Chapter 4.16 --- "Temporal changes of the concentration of procion red MX-5B in 5,000 mg/L of Ti02-alginate beads" --- p.85 / Chapter 4.17 --- "Temporal change of the concentration of procion red MX-5B in 10,000 mg/L of Ti02-alginate beads" --- p.85 / Chapter 4.18 --- Effect of the concentration of titanium dioxide in alginate beads in the photocatalytic degradation of procion red MX-5B --- p.89 / Chapter 4.19 --- "Effect of hydrogen peroxide in the photocatalytic degradation of procion red MX-5B in 5,000 mg/L of Ti02-alginate beads" --- p.89 / Chapter 4.20 --- "Temporal change of the concentration of procion red MX-5Bin alginate beads with 5,000 mg/L of Ti02" --- p.89 / Chapter 4.21 --- "Effect ofbiomass of Pseudomonas sp. K1 on the photocatalytic degradation of procion red MX-5B in 5,000 mg/L of Ti02-alginate beads" --- p.93 / Chapter 4.22 --- Degradation products analysis using diffuse reflectance-IR spectroscopy --- p.93 / Chapter 4.23 --- Degradation products analysis using nuclear magnetic resonance (NMR) --- p.101 / Chapter 4.24 --- Toxicological evaluation of degradation products using Microtox® test --- p.101 / Chapter 5 --- Discussion --- p.104 / Chapter 5.1 --- Biosorption of azo dyes in Pseudomonas sp. K-l --- p.104 / Chapter 5.2 --- Optimization of photocatalytic degradation of azo dyes --- p.105 / Chapter 5.2.1 --- Effect of initial concentration of procion red MX-5B on the photocatalytic degradation --- p.105 / Chapter 5.2.2 --- Effect of initial concentration of hydrogen peroxide on the photocatalytic degradation --- p.106 / Chapter 5.2.3 --- Effect of initial pH on the photocatalytic degradation --- p.107 / Chapter 5.2.4 --- Effect of initial temperature on the photocatalytic degradation --- p.108 / Chapter 5.2.5 --- Effect of titanium dioxide on the photocatalytic degradation --- p.109 / Chapter 5.2.6 --- Effect of UV intensity on the photocatalytic degradation --- p.110 / Chapter 5.2.7 --- Degradation kinetics of different dyes --- p.111 / Chapter 5.2.8 --- Optimized conditions for PCO of reactive red 241 and procion red --- p.112 / Chapter 5.3 --- Immobilization of titanium dioxide and Pseudomonas sp. K-l in alginate beads --- p.113 / Chapter 5.3.1 --- Temporal changes of the concentration of dye in alginate beads --- p.113 / Chapter 5.3.2 --- Effect of titanium dioxide in alginate beads in PCO --- p.114 / Chapter 5.3.3 --- Effect of hydrogen peroxide in alginate beads in PCO --- p.115 / Chapter 5.3.4 --- "Temporal change of dye concentration in alginate beads of 5,000 mg/L" --- p.115 / Chapter 5.3.5 --- Effect of biomass of Pseudomonas sp. K-l in alginate beads on the PCO of dye --- p.115 / Chapter 5.4 --- Diffuse reflectance IR spectroscopic analysis of degradation products --- p.116 / Chapter 5.5 --- 1HNMR analysis of degradation products --- p.119 / Chapter 5.6 --- Toxicological evaluation of degradation products using Microtox® test --- p.120 / Chapter 5.7 --- Application --- p.121 / Chapter 6 --- Conclusion --- p.122 / Chapter 7 --- References --- p.124 / Appendix 1 --- p.142 / Appendix 2 --- p.143

by Chan Chui Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 83-94). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / 摘要 --- p.iii / Contents --- p.iv / List of Figures --- p.ix / List of Plates --- p.xi / List of Tables --- p.xii / List of Abbreviations --- p.xiv / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Di(2-ethylhexyl)phthalate (DEHP) --- p.1 / Chapter 1.1.1 --- The chemical class of DEHP: Phthalate ester --- p.1 / Chapter 1.1.2 --- Characteristics of DEHP --- p.3 / Chapter 1.1.3 --- Sources of releases and environmental concentration --- p.4 / Chapter 1.1.4 --- Persistence of DEHP --- p.5 / Chapter 1.1.5 --- Routes of exposure --- p.6 / Chapter 1.1.6 --- Toxicity of DEHP --- p.7 / Chapter 1.1.6.1 --- Acute toxicity --- p.7 / Chapter 1.1.6.2 --- Chronic toxicity --- p.8 / Chapter 1.1.6.2.1 --- Adverse effects on reproduction system --- p.8 / Chapter 1.1.6.2.2 --- Carcinogenicity --- p.9 / Chapter 1.1.6.2.3 --- Developmental toxicity --- p.9 / Chapter 1.1.6.2.4 --- Endocrine disruption --- p.10 / Chapter 1.1.6.2.5 --- Hepatotoxicity --- p.10 / Chapter 1.1.7 --- Regulations --- p.10 / Chapter 1.2 --- Treatment of DEHP --- p.11 / Chapter 1.2.1 --- Conventional treatment technologies --- p.11 / Chapter 1.2.1.1 --- Physical method --- p.11 / Chapter 1.2.1.1.1 --- Adsorption --- p.11 / Chapter 1.2.1.1.2 --- Sonolysis --- p.12 / Chapter 1.2.1.2 --- Photochemical method --- p.13 / Chapter 1.2.1.2.1 --- Photocatalytic oxidation (PCO) --- p.13 / Chapter 1.2.1.3 --- Biological method --- p.13 / Chapter 1.2.1.3.1 --- Biodegradation --- p.13 / Chapter 1.2.1.3.2 --- Sewage treatment process --- p.14 / Chapter 1.2.2 --- Integrated treatment method in the present study --- p.15 / Chapter 1.2.2.1 --- Biosorption --- p.15 / Chapter 1.2.2.1.1 --- Definition of biosorption --- p.15 / Chapter 1.2.2.1.2 --- Advantages of biosorption --- p.16 / Chapter 1.2.2.1.3 --- Chitinous materials as biosorbents --- p.16 / Chapter 1.2.2.1.4 --- Advantages of using chitinous materials as biosorbents --- p.17 / Chapter 1.2.2.1.5 --- Modeling of biosorption --- p.19 / Chapter 1.2.2.2 --- PCO --- p.21 / Chapter 1.2.2.2.1 --- Definition of PCO --- p.21 / Chapter 1.2.2.2.2 --- Mechanism of PCO --- p.23 / Chapter 1.2.2.2.3 --- Advantages of PCO --- p.25 / Chapter 2 --- Objectives --- p.27 / Chapter 3 --- Materials and methods --- p.28 / Chapter 3.1 --- Materials --- p.28 / Chapter 3.1.1 --- Adsorbate --- p.28 / Chapter 3.1.2 --- Biosorbents --- p.28 / Chapter 3.1.2.1 --- Pretreatment of biosorbents --- p.29 / Chapter 3.1.3 --- Photocatalytic reactor --- p.29 / Chapter 3.1.4 --- Photocatalyst --- p.30 / Chapter 3.1.5 --- Electron scavenger --- p.31 / Chapter 3.2 --- Methods --- p.31 / Chapter 3.2.1 --- Determination of DEHP concentration --- p.31 / Chapter 3.2.2 --- Batch biosorption experiment --- p.32 / Chapter 3.2.2.1 --- Screening of biosorbents --- p.33 / Chapter 3.2.2.2 --- Optimization of biosorption conditions --- p.33 / Chapter 3.2.2.2.1 --- Effect of biosorbent concentration --- p.33 / Chapter 3.2.2.2.2 --- Effect of initial pH --- p.33 / Chapter 3.2.2.2.3 --- Effect of biosorption time --- p.34 / Chapter 3.2.2.2.4 --- Effect of temperature --- p.34 / Chapter 3.2.2.2.5 --- Effect of agitation rate --- p.34 / Chapter 3.2.2.2.6 --- Effect of initial DEHP concentration --- p.34 / Chapter 3.2.2.2.7 --- "Combinational effect of initial pH, chitin A concentration and initial DEHP concentration" --- p.35 / Chapter 3.2.3 --- Extraction of adsorbed DEHP from chitin A --- p.35 / Chapter 3.2.3.1 --- Screening of extraction agents --- p.36 / Chapter 3.2.3.2 --- Determination of extraction time --- p.36 / Chapter 3.2.4 --- Batch PCO experiment --- p.36 / Chapter 3.2.4.1 --- Optimization of PCO conditions --- p.38 / Chapter 3.2.4.1.1 --- Effect of reaction time --- p.38 / Chapter 3.2.4.1.2 --- Effect of UV-A intensity --- p.38 / Chapter 3.2.4.1.3 --- Effect of TiO2 concentration --- p.38 / Chapter 3.2.4.1.4 --- Effect of H2O2 concentration --- p.38 / Chapter 3.2.4.1.5 --- Effect of initial pH --- p.39 / Chapter 3.2.4.1.6 --- Combinational effect of H2O2 concentration and initial pH --- p.39 / Chapter 3.2.4.1.7 --- Effect of concentration factor --- p.39 / Chapter 3.2.4.2 --- Identification of intermediates/products of DEHP --- p.39 / Chapter 3.2.4.3 --- Evaluation for the toxicity of DEHP and the intermediates/products by the Microtox® test --- p.40 / Chapter 4 --- Results --- p.42 / Chapter 4.1 --- Batch biosorption experiment --- p.42 / Chapter 4.1.1 --- Screening of biosorbents --- p.42 / Chapter 4.1.2 --- Optimization of biosorption conditions --- p.42 / Chapter 4.1.2.1 --- Effect of biosorbent concentration --- p.42 / Chapter 4.1.2.2 --- Effect of initial pH --- p.42 / Chapter 4.1.2.3 --- Effect of biosorption time --- p.46 / Chapter 4.1.2.4 --- Effect of temperature --- p.46 / Chapter 4.1.2.5 --- Effect of agitation rate --- p.46 / Chapter 4.1.2.6 --- Effect of initial DEHP concentration --- p.46 / Chapter 4.1.2.7 --- "Combinational effect of initial pH, chitin A concentration and initial DEHP concentration" --- p.51 / Chapter 4.1.2.8 --- Summary of biosorption conditions before and after optimization --- p.54 / Chapter 4.2 --- Extraction of adsorbed DEHP from chitin A --- p.54 / Chapter 4.2.1 --- Screening of extraction agents --- p.54 / Chapter 4.2.2 --- Determination of extraction time --- p.55 / Chapter 4.3 --- Batch PCO experiment --- p.56 / Chapter 4.3.1 --- Optimization of PCO conditions --- p.56 / Chapter 4.3.1.1 --- Effect of reaction time --- p.56 / Chapter 4.3.1.2 --- Effect of UV-A intensity --- p.57 / Chapter 4.3.1.3 --- Effect of TiO2 concentration --- p.59 / Chapter 4.3.1.4 --- Effect of H2O2 concentration --- p.60 / Chapter 4.3.1.5 --- Effect of initial pH --- p.61 / Chapter 4.3.1.6 --- Combinational effect of H2O2 concentration and initial pH --- p.62 / Chapter 4.3.1.7 --- Effect of CF --- p.63 / Chapter 4.3.1.8 --- Summary of PCO conditions before and after optimization --- p.63 / Chapter 4.3.2 --- Identification of intermediates/products of DEHP --- p.64 / Chapter 4.3.3 --- Evaluation for the toxicity of DEHP and the intermediates/products by the Microtox® test --- p.66 / Chapter 5 --- Discussion --- p.68 / Chapter 5.1 --- Batch biosorption experiment --- p.68 / Chapter 5.1.1 --- Screening of biosorbents --- p.68 / Chapter 5.1.2 --- Optimization of biosorption conditions --- p.69 / Chapter 5.1.2.1 --- Effect of biosorbent concentration --- p.69 / Chapter 5.1.2.2 --- Effect of initial pH --- p.69 / Chapter 5.1.2.3 --- Effect of biosorption time --- p.70 / Chapter 5.1.2.4 --- Effect of temperature --- p.71 / Chapter 5.1.2.5 --- Effect of agitation rate --- p.71 / Chapter 5.1.2.6 --- Effect of initial DEHP concentration --- p.71 / Chapter 5.1.2.7 --- "Combinational effect of initial pH, chitin A concentration and initial DEHP concentration" --- p.73 / Chapter 5.2 --- Extraction of adsorbed DEHP from chitin A --- p.74 / Chapter 5.2.1 --- Screening of extraction agents --- p.74 / Chapter 5.2.2. --- Determination of extraction time --- p.74 / Chapter 5.3 --- Batch PCO experiment --- p.74 / Chapter 5.3.1 --- Optimization of PCO conditions --- p.74 / Chapter 5.3.1.1 --- Effect of reaction time --- p.74 / Chapter 5.3.1.2 --- Effect of UV-A intensity --- p.74 / Chapter 5.3.1.3 --- Effect of TiO2 concentration --- p.75 / Chapter 5.3.1.4 --- Effect of H2O2 concentration --- p.75 / Chapter 5.3.1.5 --- Effect of initial pH --- p.76 / Chapter 5.3.1.6 --- Combinational effect of H2O2 concentration and initial pH --- p.77 / Chapter 5.3.1.7 --- Effect of CF --- p.77 / Chapter 5.3.2 --- Identification of intermediates/products of DEHP --- p.78 / Chapter 5.3.3 --- Evaluation for the toxicity of DEHP and the intermediates/products by the Microtox test --- p.79 / Chapter 6 --- Conclusions --- p.80 / Chapter 7 --- References --- p.83

Penicillium ochro-chloron (ATCC strain # 36741), a filamentous fungus with the capability for removing copper ions from aqueous solutions, was studied as a possible biological trap (biotrap) for remediation of heavy metal contaminants in industrial wastewaters. This research demonstrated that in shake flasks the fungus removed copper from surrogate wastewater with 100mg/L copper contamination by as much as 99%. These results did not translate to the bioreactor configuration of a packed bed column, as channeling occurred through the bed, shown by conductivity tracer studies. A fluidized bed configuration was studied and resulted in copper removal of 97%, with a capacity of 149 mg[Cu]/g dry weight biomass, under the conditions of 50% dissolved oxygen. For dissolved oxygen concentrations below the critical oxygen concentration for the fungus (20% saturation) there was minimal copper removal. Mixing studies in the fluidized bed reactor showed that the system was diffusion limited. Mathematical modeling using first order kinetics associated with diffusion limited reactions resulted in rate constants for Cu 2+ uptake of approximately 0.031 h -1 , which were dependent on the dissolved oxygen concentration. Modeling of the reaction with a second order kinetic equation showed that there are possibly factors regulating copper uptake besides oxygen. Electron microscopy showed that in some instances the copper removed was retained as large porous spherical extracellular precipitates. Energy Dispersive X-ray (EDX) analysis has shown similar complexes to be copper phosphate precipitates (Crusberg, 1994). Removal of heavy metal contaminants from wastewater discharge is a necessity for many industries, due to environmental concerns and federal regulations. The use of a biological system for the removal and recycling of heavy metals could prove more economical than currently used physio-chemical processes.

Discharge of metal containing effluents into water has been a cause of major concern. Traditional treatment methods are proving to be ineffective and expensive. Chitosan was studied as a potential biosorbent due to its positive charge and relatively low cost. The study involves evaluating the metal binding performance of chitosan in a polymer enhanced diafiltration (PEDF) system which uses an ultrafiltration membrane to retain the chitosan which, in turn, binds the metal, thereby preventing passage into the permeate stream. Conditions for binding such as pH, concentration of polymer and chromium were studied. Optimal performance was obtained when the system was operated at pH values lower then the pKa of chitosan i.e. 6.3. Using 6 g/L chitosan at pH 4.0, chromium concentration was reduced to less than 1mg/L from a feed concentration of 20 mg/L. Equilibrium dialysis experiments were done to study the kinetics of binding and the uptake of metal per gram of polymer. Rheological measurements demonstrated that in the presence of 1-100 mM chromate, chitosan was found to be slightly shear-thickening at low concentrations such as 4 g/L and 6 g/L whereas it was slightly shear-thinning at higher concentrations like 12 g/L and 20 g/L This suggests that neutralization of chromium anions is due to the interaction of multiple chitosan molecules. This result is consistent with the relatively stiff nature of the polysaccharide. Overall, this study suggests that some modification of the native polymer would be required to improve uptake and make it an industrially workable process.

The application of biotechnologies in the mining sector has intensified over the last 30 years, driven by the increasing demand for metals associated with the rise in energy costs and the awareness for environmentally responsible mining practices. Acidophilic prokaryotes play an important role in biohydrometallurgy, facilitating the solubilisation and recovery of base metals from ores and waste materials. The potential of novel acidophiles of the phylum Firmicutes for applications in biohydrometallurgical processes is examined in this thesis. Eight strains of extremely acidophilic bacteria were studied and shown to belong to the proposed novel genus “Acidibacillus”. These had been isolated previously from several distinct global locations and were shown to be obligately heterotrophic bacteria with potential to carry out tasks critical to biomining such as regenerating ferric iron (by catalysing the dissimilatory oxidation of ferrous iron), generating sulfuric acid (by the oxidation of zero-valent sulfur and tetrathionate; two strains only), and removing potentially inhibitory dissolved organic carbon. These isolates also demonstrated the ability to catalyse the dissimilatory reduction of ferric iron in anaerobic conditions. Results obtained during this study provide the basis for future research to assess their potential roles in microbial consortia applied in the bio-processing of metal ores. A novel obligately anaerobic acidophilic Firmicute (strain I2511) isolated from sediment obtained from an abandoned copper mine, was characterised in terms of its phylogeny and physiology. This isolate formed a separated clade within the Firmicutes, and was considered to represent a novel candidate genus. It also displayed a unique set of physiological traits, distinct from currently validated species of acidophilic Firmicutes. The isolate was an obligate anaerobe that grew via zero-valent sulfur (ZVS) respiration, generating H2S over a wide pH range (1.8 - 5.0), and also catalysed the dissimilatory reduction of ferric iron. Strains of acidophilic sulfatereducing bacteria (aSRB), also Firmicutes, were shown to reduce ZVS at pH as low as 3. These aSRB, together with isolate I2511, populated a novel variant of a low pH sulfidogenic bioreactor. The “hybrid sulfidogenic bioreactor” (HSB) operated using both sulfate and ZVS as electron acceptors, and glycerol as electron donor. The bioreactor successfully remediated and recovered zinc from circum-neutral pH mine-impacted waters with distinct chemical composition collected from two abandoned lead/zinc mines in the U.K. The microbial consortium used in this system proved to be robust, in which the HSB generated H2S consistently under a wide pH range (2 – 7). Experiments demonstrated that H2S could also be generated abiotically in a non-inoculated low pH reactor, by the chemical reaction of ZVS and zero-valent iron to form iron sulfide, and the consequent acid dissolution of the latter. Operational costs and the advantages of biogenic and abiotic generation of H2S for recovery of transition metals from mine waters are discussed.