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Kamat, Rohit Babli. "Phytoremediation for dye decolorization." Diss., Kansas State University, 2014. http://hdl.handle.net/2097/17548.
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Doctor of PhilosophyDepartment of Biochemistry and Molecular Biophysics
Lawrence C. Davis
Synthetic dyes are capable of producing the whole color spectrum on account of their structural diversity but this diversity poses challenges in the degradation of dyeing wastes. Laccases and peroxidases from bacterial or fungal sources and parts of plants in the presence of hydrogen peroxide (H₂O₂) plus a mediator have been exploited in the bioremediation of synthetic dyes. However, intact plants have not found much favor despite their phytoremediation potential. The goal of this research was to further clarify ways by which whole plants bring about decolorization of different types of synthetic dyes. Hydroponically cultivated plants from two dicot families namely Arabidopsis thaliana and sunflowers (Helianthus annuus) were exposed to representative dyes from several classes: monoazo (Methyl Red and Methyl Orange), disazo (Trypan Blue, Evans Blue and Chicago Blue 6B), and arylmethane (Brilliant Blue G, Bromocresol Green, Malachite Green and Phenol Red). Tests were done in presence or absence of externally added H₂O₂, with or without a free radical mediator, 1-hydroxybenzotriazole, using UV-Visible spectrophotometry. The initial rate of decolorization and the overall percentage decolorization was calculated for each dye in the different treatments. Decolorization of the dyes from different classes varied between plant species and depending on the treatment. Except for Methyl Red, all dyes required added H₂O₂ as well as mediator to achieve rapid decolorization. Added H₂O₂ was found to be the limiting factor since it was degraded by plants within a few hours. Both species were able to slowly decolorize dyes upon daily addition of fresh dye even in the absence of added H₂O₂ and mediator, provided that nutrients were supplied to the plants with the dye. A. thaliana was found to be more effective in dye decolorization per gram tissue than sunflower when treated under similar conditions. Analysis of the residual dye solution by ESI/MS did not reveal any potential by-products following the decolorization treatment with plants, suggesting that the plant roots might be trapping the by-products of dye decolorization and preventing their release into the solution. All these findings support the potential application of whole plants for larger scale remediation.
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Yang, Hanbae. "Zero-Valent Iron Decolorization of the Anthraquinone Dye Reactive Blue 4 and Biodegradation Assessment of its Decolorization Products." Thesis, Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/6920.
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Anthraquinone dyes constitute the second largest class of textile dyes, and are used extensively in the textile industry. A high fraction of the initial reactive dye mass used in the dyeing process remains in the spent dyebath. Reactive dyes are not readily removed by typical wastewater treatment processes and the high salt concentration typical of reactive dyeing further complicates the management of spent reactive dyebaths. Investigation of the reductive transformation of reactive anthraquinone dyes and their decolorization products has been very limited. Additionally, very limited research has been conducted on the decolorization of spent reactive dyebaths.
Research was conducted to investigate the key operational parameters of batch and continuous-flow ZVI decolorization of a reactive anthraquinone dye, Reactive Blue 4 (RB4), under anoxic conditions, as well as the potential for the biodegradation of its decolorization products in a halophilic culture under aerobic conditions. The effect of two operational parameters, such as mixing intensity and initial dye concentration, on the ZVI batch decolorization kinetics indicates that ZVI decolorization of RB4 is a surface-catalyzed, mass transfer-limited process. The high salt and base concentrations enhanced the rate of RB4 decolorization. Based on parameters such as porosity, hydraulic conductivity, pore water velocity, and dispersion coefficient, non-ideal transport characteristics were observed in a continuous-flow ZVI column. The results of a long-term continuous-flow ZVI decolorization kinetics demonstrated that continuous-flow ZVI decolorization is feasible. However, column porosity losses and a shift of reaction kinetics occur in long-term column operation. ZVI decolorization of RB4 was successfully described with a pseudo first-order or a site saturation model. Lastly, the RB4 decolorization products generated by ZVI treatment had no inhibitory effect on the halophilic culture. However, biodegradation and/or mineralization of RB4 decolorization products was not observed after a long-term incubation of the culture.
This research demonstrated the feasibility of ZVI decolorization of reactive anthraquinone dyes, which will help in the development of a continuous-flow, dyebath decolorization process and the possible reuse of the renovated dyebath in the dyeing operation. Such a system could lead to substantial reduction of water usage, as well as a decrease of salt and dye discharges.
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Duygulu, Yusuf Bahadir. "Decolorization Of Synthetic Dye Solutions By Using Basaltic Tephra And Clinoptilolite." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605241/index.pdf.
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Discharge of colored effluents without decoloration originated from textile industries may cause serious problems in the receiving environments.
In this study, natural materials that are basaltic tephra and clinoptilolite were used to remove various dyestuffs used in the textile industry. Those materials are cheap and available in large quantities in Turkey. The investigation of adsorption of basic, acidic and reactive dyes on these materials is the objective of this study.
During preliminary experiments it was seen that adsorption equilibrium was reached in about 2 days. In adsorption experiments, in order to obtain adsorption isotherms, a fixed amount of adsorbent and 100 mL dye solutions of different concentrations were placed in glass bottles which were shaken at 200 rpm and 25±2oC for 2 days. Then, samples were filtered and the equilibrium concentrations of dyestuffs in the solutions were determined by using spectrophotometer at appropriate wavelength corresponding to the maximum absorbency. After equilibrium concentrations of the solutions were obtained, Langmuir and Freundlich adsorption isotherm constants were calculated for the adsorbents used in this study. The removal efficiencies for cationic basic dyes are higher than those for anionic acidic and reactive dyes with the natural materials. Therefore, modification of surface properties of natural materials with a cationic surfactant was considered to increase the removal efficiencies of those for anionic dyes. After modification of the surface properties, adsorption capacities of adsorbents for anionic dyes were higher than those of natural materials. Finally, the adsorption capacity of activated carbon for the same dyes was determined to compare with that of natural and modified materials. The results showed that the adsorption of dyes on adsorbents used in this study fitted nicely the Langmuir Isotherm Equations.
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Iseppi, Daniela <1987>. "Chemometric analysis of the photooxidative decolorization of the azo dye Acid Red 97." Master's Degree Thesis, Università Ca' Foscari Venezia, 2012. http://hdl.handle.net/10579/1512.
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Dykstra, Christine M. "Decolorization of an azo and anthraquinone textile dye by a mixture of living and non-living Trametes versicolor fungus." Honors in the Major Thesis, University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/375.
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Wastewater from the textile industry is difficult to treat effectively due to the prevalent use and wide variety of synthetic dyes that are resistant to conventional treatment methods. White-rot fungi, such as Trametes versicolor, have been found to be effective in decolorizing many of these synthetic dyes and current research is focusing on their application to wastewater treatment. Although numerous studies have been conducted on the ability of both living and nonliving Trametes versicolor to separately decolorize textile dyes, no studies were found to have investigated the use of a mixture of live and dead fungus for decolorization. This study explored potential interactions between live and dead, autoclaved Trametes versicolor biomass in a mixed system by utilizing a series of batch tests with two structurally different synthetic textile dyes. Samples were analyzed by spectrophotometer and compared with controls to determine the effect of any interactions on decolorization. The results of this study indicate that an interaction between living and nonliving biomass occurred that affected the specific dye removal for both Reactive Blue 19, an anthraquinone textile dye, and Reactive Orange 16, an azo textile dye. This interaction was seen to improve the specific dye removal during the first 10-46 hours of experimentation but then diminish the specific dye removal after this period. This effect could be due to hydrophobins, which are surface-active proteins excreted by live fungi that may alter hydrophobicity. Additionally, the presence of adsorptive dead biomass could affect dye contact with degrading enzymes released from the live fungus. By expanding current knowledge of the interactions that take place in a fungal bioreactor and their effect on textile dye decolorization, this research aims to inspire more effective and less costly bioreactor designs for the treatment of textile wastewater.B.S.Env.E.
Bachelors
Engineering and Computer Science
Environmental Engineering
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Ribeiro, Jefferson Pereira. "Estudo da OtimizaÃÃo do Processo H2O2/UV para degradaÃÃo do Corante Remazol Vermelho RB 133%." Universidade Federal do CearÃ, 2011. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=6525.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoAs atividades industriais que consomem excesso de Ãgua no seu processo industrial, geralmente geram um elevado volume de efluentes, onde a indÃstria tÃxtil à um exemplo tÃpico. A oxidaÃÃo quÃmica à um dos processos alternativos para o tratamento de efluentes contendo corantes tÃxteis, entre eles destacam-se os POAs que sÃo baseados na geraÃÃo de radicais hidroxilas (.OH) no qual sÃo altamente oxidantes, podendo decompor compostos de maneira rÃpida e nÃo-seletiva, conduzindo a mineralizaÃÃo parcial ou completa do contaminante. O presente trabalho estudou o uso de processo oxidativo avanÃado para a degradaÃÃo do corante Remazol Vermelho RB 133%. Os estudos foram realizados em duas etapas. Na primeira etapa, no reator com 710 mL de volume Ãtil, foram realizados estudos de otimizaÃÃo dos parÃmetros: cinÃtica de descoloraÃÃo, dosagem do perÃxido de hidrogÃnio, pH, temperatura, adiÃÃo de perÃxido de hidrogÃnio em linha. A cinÃtica de descoloraÃÃo, e o efeito inibitÃrio de Ãnions tambÃm foram estudados. O estudo de cinÃtica mostrou que em 250 minutos houve uma descoloraÃÃo completa da soluÃÃo usando uma dosagem de perÃxido de hidrogÃnio de 1% H2O2 mediante o uso da radiaÃÃo UV. Nestas condiÃÃes houve uma remoÃÃo de 78,41% na DQO. O pH nÃo influenciou no processo de descoloraÃÃo da soluÃÃo, em contraste, para valores de pH iniciais 8 e 10 houve uma maior remoÃÃo na DQO. O estudo do efeito da temperatura do sistema mostrou que com o aumento temperatura a velocidade de descoloraÃÃo à pouco influenciada, ao passo que o aumento da temperatura (80ÂC) diminuiu a eficiÃncia do processo de remoÃÃo da DQO. A adiÃÃo de H2O2 em linha do processo aumentou a eficiÃncia na remoÃÃo de DQO. Os resultados das eficiÃncias de remoÃÃo ao final do processo indicaram que nÃo houve diferenÃa entre os tratamentos na presenÃa dos Ãnions na concentraÃÃo estudada (10 mM) quando comparada a degradaÃÃo sem a presenÃa desses Ãnions, pois ao final de todos os tratamentos a soluÃÃo ficou incolor. Na segunda etapa, no reator com 520 mL de volume Ãtil, foram realizados estudos de vazÃo e potÃncia de radiaÃÃo UV. O estudo mostrou que para as vazÃes estudadas 1,0; 2,0 e 3,0 L/min nÃo houve uma X diferenÃa significativa no processo de descoloraÃÃo. As concentraÃÃes da matÃria orgÃnica ao final de 480 minutos de experimento para as trÃs vazÃes foram 36,63%; 51,08% e 48,35%, respectivamente. O aumento da potÃncia de radiaÃÃo UV proporcionou um aumento na eficiÃncia do processo de descoloraÃÃo e degradaÃÃo da matÃria orgÃnica. O estudo com efluente real mostrou uma baixa eficiÃncia na reduÃÃo de cor e de demanda quÃmica de oxigÃnio.
Industrial processes that consume excess of water, typically generates a high volume of effluent, where the textile industry is a typical example. The oxidation chemistry is one of the alternative processes for the textile dyes treatment. In this context, the Advanced Oxidation Processes (AOPs) are based on the generation of hydroxyl radicals (.OH) on which are highly oxidizing compounds can decompose quickly and non-selective contaminant solutes, for a partial or complete mineralization. This study investigated the use of advanced oxidation process for degradation of the dye Remazol Red RB 133%. The studies were conducted in two stages. For first step, in the reactor with 710 mL of working volume , were studies the parameters: kinetic effect, hydrogen peroxide dosage, temperature, pH, addition of hydrogen peroxide in the line. The kinetics study decolorization and the inhibitory effect of anions were also studied. The study of kinetic showed that in 250 minutes there was a complete decolorization of the solution using a H2O2 dose of 1% (v/v) through the use of UV radiation, and a 78.41% removal in Chemical Oxygen Demand (COD) was observed. The pH effect not influenced in the decolorization process; however has been influenced in removal of COD. The study of temperature effect showed that for an increase in temperature the decolorization rate increases, but a small improvement in the efficiency of COD removal. The addition of H2O2 during the process increased the efficiency of COD removal. The results of the efficiencies of the end of the process indicated that there was no difference between treatments in the presence of anions in the studied concentration (10 mM) when compared to degradation without the presence of these anions, since the end of all treatments, the solution was colorless. In the second stage, was carried in the reactor with 520 mL of working volume flow studies were performed and power of UV radiation. The studies of flow rate showed that for flow rate of 1.0; 2.0 and 3.0 L/min there was no significant difference in the process decolorization process. The of organic matter concentrations at 480 minutes of experiment for the three flow rates were 36.63%, 51.08% and 48.35% respectively. The increased power of UV radiation caused an increase in the XII efficiency of discolouration and degradation of organic matter. The study showed a real effluent with low efficiency to reduce color and chemical oxygen demand.
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Mezohegyi, Gergo. "Catalytic azo dye reduction in advanced anaerobic bioreactors." Doctoral thesis, Universitat Rovira i Virgili, 2010. http://hdl.handle.net/10803/8593.
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En un reactor anaeróbico de lecho empacado y de flujo ascendente con carbón activado (AC) biológico se obtuvieron altas velocidades de conversión del colorante azoico Acid Orange 7 a tiempos espaciales muy cortos, hasta 99% en 2.0 min. Tanto el área superficial específica como la conductividad electrónica del AC contribuyeron a las mayores velocidades de reducción. La agitación en el lecho de carbón produjo un incremento de la bioconversión del colorante. Se estableció un modelo cinético de decoloración que implica catálisis heterogénea y bioreducción. La biodegradabilidad anaeróbica de un colorante azoico en el sistema reactivo agitado pudo ser predicha a partir de su potencial de reducción. Las velocidades de decoloración fueron significativamente influenciadas por las propiedades texturales del AC y moderadamente afectadas por su química superficial. Este bioreactor catalítico parece ser una alternativa atractiva para la mejora económica de las tecnologías de tratamiento de aguas residuales textiles y de colorantes.In an anaerobic upflow packed-bed reactor with biological activated carbon (AC), high azo dye Acid Orange 7 conversion rates were achieved during very short space times up to 99% in 2.0 min. Both electron conductivity and specific surface area of AC contributed to higher reduction rates. The application of stirring in the carbon bed resulted in an increase of dye bioconversion. A decolourisation model was developed involving both heterogeneous catalysis and bioreduction. The anaerobic biodegradability of an azo dye could be predicted by its reduction potential in the stirred reactor system. The decolourisation rates were found to be significantly influenced by the textural properties of AC and moderately affected by its surface chemistry. This catalytic bioreactor system seems to be an attractive alternative for economically improving textile/dye wastewater technologies.
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Yang, Fangfang. "Targeted supported laccase based hybrid catalyst for continuous flow catalysis." Electronic Thesis or Diss., Ecole centrale de Marseille, 2021. http://www.theses.fr/2021ECDM0009.
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Les catalyseurs hétérogènes sont aujourd’hui'hui largement développés afin d'obtenir une meilleure stabilité, une meilleure réutilisation ainsi qu'une meilleure localisation. Dans cette optique, nous avons d'abord préparé des catalyseurs hétérogènes à base d'enzymes par l'immobilisation d’une laccase d'origine fongique contenant seulement deux lysines de surface spatialement proches (K40, K71) ainsi que deux de ses variants contenant une lysine unique -une située à proximité du site d'oxydation du substrat (K157) et une à l'opposé de ce site d'oxydation (K71)- dans des mousses de silice de type Si(HIPE) à porosités contrôlées. L'immobilisation a été réalisée par liaison covalente entre l'enzyme et la mousse activée à faible teneur en glutaraldéhyde. En testant la décoloration de colorants dans un réacteur à flux continu, nous montrons que l'activité du catalyseur hétérogène est comparable à son homologue homogène. Son activité opérationnelle reste aussi élevée que 60 % après douze cycles de décoloration consécutifs et un an de stockage. Plus important encore, en comparant les activités sur différents substrats pour des catalyseurs orientés différemment, nous montrons une discrimination double pour l'ABTS par rapport à l'ascorbate. Par ailleurs, les métalloenzymes artificielles peuvent utiliser les avantages des catalyseurs métalliques et enzymatiques pour réaliser une oxydation aérobie de manière durable. Nous avons donc immobilisé un complexe Pd(II) à base de biquinoline et une laccase dans des monolithes de silice pour l'oxydation de l'alcool veratrylique. Afin de contrôler la réactivité, trois méthodes d'immobilisation ont été utilisées pour la construction de ces catalyseurs hybrides hétérogènes. Les catalyseurs hybrides immobilisés présentent une activité améliorée par rapport au complexe de Pd immobilisé seul pour chaque méthode testée, attestant de la synergie entre le Pd et la laccase. En modulant l'orientation de l'enzyme vers le complexe de Pd(II) et la mousse de silice, nous montrons que l'activité de l'hybride de Pd(II)/UNIK157 est en moyenne deux fois plus importante que celle de Pd(II)/UNIK71. Une bonne stabilité et réutilisation est observée quel que soit l'orientation de l'enzyme. Cette étude donne un aperçu de l'utilisation de supports solides qui au-delà de permettre la stabilité et la réutilisation deviennent des partenaires synergiques dans le processus catalytiqueHeterogeneous catalysts are now widely developed to obtain improved stability, reusability, and localization. In this view, we first prepared the enzyme-based heterogeneous catalysts by the immobilization of a fungal laccase containing only two spatially close surface lysines (K40, K71) and its variants containing a unique lysine -one located in the vicinity of the substrate oxidation site (K157) and one at the opposite side of this oxidation site (K71)- into Si(HIPE) type silica foams bearing controlled porosities. Immobilization was achieved by a covalent bond forming reaction between the enzyme and the low glutaraldehyde activated foam. Testing dye decolorization in a continuous flow reactor, we show that the activity of the heterogeneous catalyst is comparable to its homogeneous counterpart. Its operational activity remains as high as 60 % after twelve consecutive decolorization cycles and one-year storage. More importantly, comparing activities on different substrates for differentially oriented catalysts, we show a two-fold discrimination for ABTS relative to ascorbate. In addition, artificial metalloenzymes can use the advantages of both metallic and enzymatic catalysts to perform aerobic oxidation in a sustainable fashion. We thus co-immobilized a biquinoline-based-Pd(II) complex and laccase into silica monoliths for veratryl alcohol oxidation. To address the control of reactivity, three methods of immobilization were used for the construction of the heterogeneous hybrid catalysts. The immobilized hybrid catalysts show an improved activity compared to the immobilized Pd complex alone for each tested method, attesting for the synergy between Pd and laccase. By tuning enzyme orientation towards Pd(II) complex and silica foam, we show that the activity of the Pd(II)/UNIK157 hybrid exhibits an averaged two-fold increase compared to Pd(II)/UNIK71. A good stability and reusability is observed for both enzyme orientations. This study provides insights into the use of solid supports that beyond allowing stability and reusability becomes synergistic partners in the catalytic process
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Matthews, Rosalyn D. "Transformation and decolorization of reactive phthalocyanine." Diss., Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04062004-164728/unrestricted/matthews%5Frosalyn%5Fd%5F200312%5Fphd.pdf.
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Thesis (Ph. D.)--School of Civil and Environmental Engineering, Georgia Institute of Technology, 2004. Directed by Spyros G. Pavlostathis.Vita. Includes bibliographical references (leaves 381-393).
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Beydilli, Mumtaz Inan. "Reductive biotransformation and decolorization of reactive azo dyes." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/21451.
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Lee, Young H. "Reductive biotransformation and decolorization of reactive anthraquinone dyes." Diss., Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04062004-164708/unrestricted/lee%5Fyoung%5Fh%5F200312%5Fphd.pdf.
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Thesis (Ph. D.)--School of Electrical and Computer Engineering, Georgia Institute of Technology, 2004. Directed by Spyros G. Pavlostathis.Vita. Includes bibliographical references (leaves 332-345).
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Fontenot, Eric John. "Decolorization of selective reactive blue dyes under methanogenic conditions." Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/21697.
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Yoo, Eui Sun. "Biological and chemical mechanisms of reductive decolorization of azo dyes." [S.l.] : [s.n.], 2000. http://edocs.tu-berlin.de/diss/2000/yoo_eui.pdf.
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Supaka, Nuttapun. "Microbial decolorization of reactive dyes in an anaerobic : aerobic treatment system." Toulouse, INPT, 2003. http://www.theses.fr/2003INPT031G.
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Dans ce travail, des souches bactériennes isolées d'unitéss de traitement d'effluents de l'industrie textile, ont été étudiées pour leur aptitude à dégrader des colorants. Une culture mixte A5-S1 s'est révélée la plus efficace sur des colorants de type azoi͏̈que et anthraquinone. Les souches ont été identifiées, elles appartiennent au genre Paenibacillus. Les conditions expérimentales ont été définies, cuivre et nitrates se sont avérés inhibiteurs. L'anthraquinone-2,6-disulfonate accélère la décoloration par la souche A5. Cette quinone est réduite enzymatiquement en hydroquinone qui ensuite réduit chimiquement le colorant azoi͏̈que hors de la cellule. Il a été suggéré un rôle actif de la NADH quinone oxydoréductase membranaire dans cette réduction. Un réacteur à lit fluidisé mettant en oeuvre des cellules immobilisées dans des billes d'alginate a été utilisé en réacteur batch séquentiel : la décoloration s'effectue en anaérobiose suivie de l'abattement de la DCO en aérobiose.
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Silva, Michelle Reis da. "Estudo da enzima Horseradish peroxidase (HRP) no descoramento dos corantes têxteis Azul Drimaren X-3LR, Azul Drimaren X-BLN, Rubinol Drimaren X-3LR e Azul Drimaren CL-R." Universidade do Estado do Rio de Janeiro, 2008. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=2757.
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O presente trabalho avaliou o potencial da enzima HRP no descoramento dos corantes têxteis: Azul Drimaren X-3LR (DMBLR), Azul Drimaren X-BLN (DMBBLN), Rubinol Drimaren X-3LR (DMR) e Azul Drimaren CL-R (RBBR). Parâmetros como concentração do corante, temperatura, concentração de peróxido de hidrogênio (H2O2) e tempo de reação foram otimizados. Os ensaios de descoramento dos corantes foram realizados a partir desses resultados. As melhores condições reacionais determinadas para os corantes estudados foram: concentração do corante = 120 mg L-1, temperatura = 35C, concentração de H2O2 = 0,55 mM e tempo de reação = 1 hora. Os percentuais de descoramento dos corantes DMBLR, DMBBLN, DMR e RBBR, após o tratamento enzimático foi de 99, 77, 94 e 97%, respectivamente. O tempo reacional de 5 minutos foi suficiente para os corantes DMBLR e RBBR apresentarem elevada porcentagem de descoramento, 96% para ambos. Já os corantes DMBBLN e DMR só apresentaram elevado grau de descoramento após 1 hora de reação, sendo o corante DMBBLN o mais recalcitrante, apresentando uma melhora de 10% na porcentagem de descoramento, após 24 horas de reação. Além do grau de descoramento, também foi avaliada a toxicidade dos corantes antes e após o tratamento enzimático utilizando Daphnia pulex e Artemia salina como bioindicadores de toxicidade. Resultados toxicológicos utilizando Daphnia pulex não foram conclusivos, indicando que esse bioindicador não foi adequado para avaliar a toxicidade dos corantes estudados no meio reacional utilizado. Com o uso da Artemia salina na avaliação toxicológica foi observado uma redução da toxicidade para os corantes DMBLR, DMR e RBBR após tratamento enzimático, e um aumento da toxicidade não significativo para o corante DMBBLN. Os resultados obtidos no trabalho ressaltam a eficiência da enzima HRP no descoramento dos corantes têxteis estudados, sem a geração de produtos tóxicos e prejudiciais ao meio ambienteThe aim of the present study was to evaluate the potential of the Horseradish peroxidase (HRP) enzyme in the decolorization of textile dyes Drimaren Blue X-3LR (DMBLR), Drimaren Blue X-BLN (DMBBLN), Drimaren Rubinol X-3LR (DMR) and Drimaren Blue CL-R (RBBR). Parameters such as concentration of the dye, temperature, concentration of hydrogen peroxide (H2O2) and reaction time were optimized. The optimum reaction conditions determined for the studied dyes were: concentration of the dye = 120 mg L-1, temperature = 35 C, concentration of H2O2 = 0.55 mM and reaction time = 1 h. The decolorization percentage of dyes DMBLR, DMBBLN, DMR and RBBR after enzymatic treatment was 99, 77, 94 and 97%, respectively. The reaction time of only 5 minutes presented high decolorization percentage for both dyes DMBLR and RBBR, about 96 %. However dyes DMBBLN and DMR showed high decolorization degree in 1 h of reaction and the dye DMBBLN, being the most recalcitrant, exhibited an improvement of 10% in the decolorization percentage after 24 h of reaction. Besides the decolorization degree, the toxicity of the studied dyes was also evaluated before and after enzymatic treatment using Daphnia pulex and Artemia salina as bioindicators. The toxicological results using Daphnia pulex were not conclusive, indicating that it was not an appropriate bioindicator to evaluate the toxicity of the tested dyes. Meanwhile when using Artemia salina for toxicological evaluation it was observed a reduction of toxicity for dyes DMBLR, DMR and RBBR after enzymatic treatment, and a not significant increase in toxicity for the dye DMBBLN. In conclusion, the obtained results emphasize the efficiency of the HRP enzyme in the decolorization of the studied textile dyes, without the generation of toxic and harmful products to the environment
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Liaw, Woei-Deng, and 廖偉登. "Photocatalytic Decolorization of Dye Wastewater." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/60094022415874169283.
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碩士國立中山大學
環境工程與科學系
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Near-UV illuminated slurries of titanium dioxide were used to invesgated decolori-zation of Methylene blue in aqueous solution in a isotherm batch reactor. The results show that the optimal conditions are pH=3 and TiO2=0.5g/L. As a result, the color removal of 98.2% could be achieved in 60min, with initial concentration of 10 μ M. The Kinetics of photocatalytic decolorization of Methylene blue follw a pseudo-first order reaction, with an observed reaction constant Kobs of 0.067 min^(-1). The reaction rates of decolorization are signifantly increased in the present of 5mM H2O2. The reaction rate of decolorization decrease as the concentrations of inorganic additives (e.g. Na2CO3, NaCl, Na2SO4) increases. Moreover, The rates of decolorization and TOC removal increase as the temperatures increase. The activation energy for the reaction of decolorization is 14.45 kJ/mole, and it would reduce to 12.1 kJ/mold after added5mM H2O2 in aqueous solution. The decolorization of Direct Blue 1 with far-UV/H2O2 system were investigated in a isotherm batch reactor. The results show that the optimal condition are pH=3 and H2O2=0.833 g/L. As a result, the color removal of 98.6% could be achieved in 180 min with initial concentration of 50mg/L. The kinetics of photocatalytic decolorization of Direct Blue 1 follow a pseudo-first order reaction, with an observed reaction constant Kobs of 0.024 min^(-1). The rates of decolorization decrease as the concentration of inorganic additives increase. The rates of decolorization increase slightly as the temperatureincrease. However, the concentration of total organic carbon would decreaseobviously after treatment in the period of 180min.
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Yang, Meng-Yi, and 楊孟怡. "Decolorization of Dye Wastewater withRecycled Alum Coagulant." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/79562933155637172063.
Full textAbstract:
碩士淡江大學
水資源及環境工程學系
91
In this research, Polyaluminum Chloride(PAC) coagulation of synthetic textile wastewater was investigated. The effects of operating variables including pH and dosage on the efficiency of coagulation were studied in the jar-test. Sludge produced from PAC coagulation of synthetic textile wastewater was either acid-treated or base-treated to compare the performance of Alum recovery. The feasibility of applying recovered alum as a coagulant for color removal in coagulations of synthetic textile wastewater was evaluated. Coagulation was assessed principally in terms of color removal, colloid surface charge (zeta potential) and Al residual. Acid-treated and Based-treated sludge have been assessed in terms of Al recovery, dissolved color, and reductions of sludge volume and sludge weight. The results indicate that the optimum pH is 6 and recommended dose is 10 ~ 20 mg/L Al for PAC coagulation. The addition of flocculant has no influence to color removal, but is helpful to the precipitation of sludge by mechanism of particle bridging. Acid-treated and base-treated processes are both able to dissolve aluminum and color from sludge. At pH 2 the acid-treated sludge recovers 91.7％ Alum from original sludge, while the base-treated sludge at pH 12 recovers only 10.2％ Alum from original sludge. In terms of the amount of alum recovered per mg of acid or base added, the acid-treated process at pH 2 performed better than the based-treated process at pH 12. The effects of pH and dosage on color removal efficiency, Zeta Potential, Alum residual, sludge volume and sludge weight by coagulation using recovered Al is similar to that using fresh Al where the efficiency of color removal using recovered Al is about 97% of that using fresh Al at dosage of 5.5 mg/L and pH 3 ~ 8. Whereas, the residual color after treated with recovered Al is still high, so coagulation using combination of fresh Al and recovered Al is tested. Comparing the residual color, coagulation using combination of fresh Al and recovered Al performed better than that using recovered Al alone. At Al dosage of 10 mg/L, up to 50% of dose can replaced with recovered Al without impeding the performance of color removal. Due to the color residual after coagulation treatment using recovered Al is higher than using fresh Al, it’s recommended that the dose of fresh Al should be higher than that of recovered Al when recovered Al and fresh Al are used in combination for coagulation of dye waste.
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Huang, Wen Tsung, and 黃文聰. "Studies on decolorization of dye by microbiol." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/62386878395869054307.
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Jin-Yen, Ho, and 何俊穎. "Analysis of metabolites from microbial azo dye decolorization." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/98203670416186128972.
Full textAbstract:
碩士逢甲大學
化學工程學系
88
The biotechnology was one of the most efficient methods in the decolorization of wastewater. The decolorization mechanisms of a reactive azo dye (C.I. Reactive Red 22) from wide-type Pseudomonas luteola strain and recombinant Escherichia coli strain (E. coli NO3) were investigated. The concentration of bacterial cell and Reactive Red 22 was obtained from the ultraviolet-visible photospectrometer. The decolorization products was first separated by reserved phase column of HPLC, then identified by mass spectrometry. It was also found that the time required for complete decolarization of Reactive Red 22 (200ppm) was shorten around 6-7 h with the addition of the metabolites from decolorization of high concentration of Reactive Red 22 (2000ppm) with E. coli NO3.
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Lin, Yu-Chih, and 林毓智. "Bioreactor Operation Strategies for Microbial Azo Dye Decolorization." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/21743674303457519800.
Full textAbstract:
碩士逢甲大學
化學工程學系
87
Abstract This study utilized Pseudomonas luteola as the biocatalyst and reactive red 22 as the model substrate to investigate microbial decolorization of azo dye in shake-flask and 5 L fermenter. The effect of medium composition on the decolorization of reactive red 22 by P. luteola was studied in shake-flask mode. The results show that yeast extract and tryptone stimulated the efficiency of decolorization, achieving a specific decolorization rate of up to 18 mg dye/g cell/h and a conversion of 95Vo or higher. The yield coefficient of yeast extract relative to dye decolorization was about 1.1957 g/g. The decolorization terminated as the yeast extract concentration was below a critical value of around 0.05@0. Despite being an efficient carbon source for the growth of P. luteola, glucose strongly inhibited the decolorization of reactive red 22, probably due to the effect of catabolic repression that could hinder the expression of azoreductase. Bioaccumulation of the dye on the biomass of P. luteola was clearly observed when glucose was presence in the reaction mixture. For decolorization bioreactor studies, repeated-batch and fed-batch operations were conducted. Optimal feeding policy and operation conditions for the decolorization bioreactor were approached by investigating a variety of operation factors, including dye feeding concentration, agitation and aeration speed, dye and medium feeding strategies, initial culture volume, etc.. With repeated-batch operation, the best decolorization rate was 107.9 mg dye/g cell/h at a feeding concentration of 300 mg/L. As the agitation speed was higher than 200 rpm, the color removal rate was significantly decreased due to a higher dissolved oxygen level. Consequently, aeration should be avoided for the microbial decolorization operation. In fed-batch operations, the decolorization reached a steady state (i.e., the amount of dye loaded equals to the amount of dye degraded) for a dye- feeding rate of 50 to 200 mg/h. The total amount of biomass did not affect the specific decolorization rate, but increasing the amount of biomass led to an enhancement of overall color removal efficiency. In fed-batch operations with simultaneous feeding of dye and yeast extract, the feeding ratio of yeast extract to dye (Y/D) should exceed 0.5 for a stable long-term operation. For a Y/D ratio of 0.5 to 1.875, the increase in yeast extract loading did not appreciably enhance the performance of the microbial decolorization, which is most likely due to mass transfer restriction in the bioreactor.
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MONACO, MARIKA MICHELA. "Photocatalytic degradation of reactive dyes by visible light and innovative Fe-doped titania catalysts." Doctoral thesis, 2018. http://hdl.handle.net/11573/1276457.
Full textAbstract:
Reactive dyes are the largest class of dyes used in the textile industry. They were selected for the present study because the treatment of wastewaters containing these dyes by conventional methods is often inadequate due to their resistance to biological and chemical degradation. The use of reactive dyes for textile dyeing has increased steadily over the last few years because of theirs cost effectiveness and excellent wash and light fastness properties. However, these dyes exhibit a very low degree of fixation on the fibers, typically between 50 and 90%, which results in the release of substantial amounts of the compounds in the dyeing water. The dyeing water cannot be reused, so dye recovery is not an option with reactive dyes. The high aromaticity and low reactivity of these dyes make them highly resistant to both microbial and chemical degradation. Physical treatments are not efficient because they transfer the toxic dyes from one medium to the other, without converting them to harmless non-toxic substances.
The development of novel treatment methods, called Advanced Oxidation Processes (AOPs), characterized by production of the hydroxyl radical (·OH) as a primary oxidant, could represent a solution. The application of these AOPs, alone or simultaneously, could enhance ·OH radical production leading to higher oxidation rates.
In this work, the photocatalytic oxidative decolorization of various reactive dyes, Reactive Blue 4, Reactive Red 120 and Reactive Violet 5, under exposure to visible light and in the presence of new semiconductor catalysts, was investigated.
The results suggest that Reactive Blue 4 is highly unstable under exposure to visible light, thus the presence of photocatalysts is not necessary for the degradation of this dye.
The Reactive Red 120 cannot be treated by direct irradiation and it cannot be decolorized even in the presence of photocatalysts.
The other results obtained indicate that the photocatalytic treatment under visible light can be an effective method for the removal of Reactive Violet 5 from textile effluents.
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郭泰興. "Azo dye decolorization with genetically modified Escherichia coli strains." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/01522505620890842582.
Full textAbstract:
碩士逢甲大學
化學工程學系
88
A genetically modified Escherichia coli NO3 strain was used to study the kinetics of azo-dye decolorization. The genetic manipulation and screening of the decolorizing strain was demonstrated. The effects of medium composition, biocatalyst types (suspended or immobilized), and metabolites on decolorization kinetics were investigated. The efficiency of repeated uses of the biocatalyst was also evaluated to assess its feasibility in practical application for color-removal of dye-containing wastewater. The results show that the recombinant plasmid harbored by E. coli NO3 may not contain genes encoding for the decolorization ability, which could originate from genes located on the chromosome. The medium composition is critical to the decolorization efficiency. It was found that decolorization with LB broth was the most effective. The optimal decolorization rates for suspended and immobilized cells were 92.6 and 28.4 mg/g cell/h, respectively, both occurred at a dye concentration of 2000 mg/L. This indicates that the strain can be operated at high dye concentrations for color removal. Decolorization was inhibited as the temperature was higher than 47oC. The suspended cells of E. coli NO3 exhibited better decolorization ability at a pH range of 7-9, while decolorization with the immobilized cells were insensitive to pH. Decolorization could not take place when the dissolved oxygen level exceeded 0.5 mg/L. In general, the decolorization rate of suspended cells was superior to that of immobilized ones. After repeated batch operations, the specific decolorization rate was enhanced to nearly 100 mg/g cell/h, probably due to the presence of decolorization metabolites. Long-term repeated batch tests conducted in a 500-mL bioreactor showed that E. coli NO3 exhibited excellent stability as it maintained high decolorization rates after consecutive operation for 48 days.
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Huang, Johnson, and 黃章誠. "Decolorization of azo dye RED RBN by immobilized cells." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/19965263626987225197.
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CAI, XING-YUAN, and 蔡杏元. "Efficient Decolorization of Azo Dye by White-rot Fungi." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/f2647f.
Full textAbstract:
碩士中華科技大學
健康科技研究所在職專班
106
Dyes released by the textile industries pose threat to environment. In this study, the white-rot fungus has been evaluated for the removal of textile dyes containing methyl orange and methyl red. A full factorial central composite design was employed for experimental design and optimization of results. The effect of concentrations of azo dye, potato dextrose broth, temperature and pH on dye removal was evaluated. Response surface methodology (RSM) was applied to optimize the decolorization of the methyl orange and methyl red dyes. The removal of methyl orange and methyl red dyes increased with the temperature and pH. Results show that the optimum temperature and pH for decolorization process were found to be 30℃ and pH 7.0, respectively.
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Chou, Chien, and 周劍. "Decolorization of Azo Dye Using Immobilized Cells of Pseudomonas luteola." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/53757751903013489652.
Full textAbstract:
碩士逢甲大學
化學工程學系
87
A Pseudomonas luteola strain capable of decolorizing the azo-dye-containing wastewater was utilized to investigate the kinetics of removing the color of azo dye (C.I. Reactive red 22). The study aimed to establish the growth kinetics of P. luteola, as well as kinetics of azo dye decolorization with suspended cells and with the cells immobilized with three different immobilization matrices (calcium alginate, k-carrageenan, and polyacrylamide). The effects of temperature, pH, and dye concentration were investigated to determine the key factors of azo dye decolorization with a series of batch operations using suspended and immobilized cells of P. luteola. The optimal preparation strategies for cell immobilization were determined. Repeated batch decolorization was also conducted to investigate the operation stability and regeneration efficiency of the immobilized cells, in order to evaluate the potential of using the immobilized cells for removing the color of dye-containing industrial effluents. The experimental results show that the effects of environmental factors (temperature, pH, substrate concentration, etc..) on decolorization of reactive red 22 were similar for both suspended and immobilized cells. In general, operations at temperatures higher than 47℃ were unfavorable. Changes in pH did not appreciably affect the decolorization efficiency of the immobilized cells, while for suspended cells a slightly better decolorization rate occurred under weak basic conditions. Of the three immobilized cells tested, calcium alginate (CA)-immobilized cells exhibited the best mass transfer efficiency, followed by k-carrageenan (CG)-immobilized cells and polyacrylamide (PAA)-immobilized cells. However, the structural stability decreased in the order of PAA-cells > CA-cells > CG-cells. The three immobilized cells showed high equilibrium conversion efficiencies of around 95-98%, which is similar to that for suspended cells. For the comparison of the kinetic properties of the three types of immobilized cells at 28℃ and pH 7, they all exhibited similar specific decolorization rates of around 3.0 to 4.0 mg dye/g cell/h, which is only 1/3 of that obtained from the suspended cells. With an initial dye concentration of 200 mg/L, the time required for a 50% conversion (t1/2) was in the range of 7 - 9 h for CA- and CG-immobilized cells, whereas a longer t1/2 was observed for PAA-immobilized cells.
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Yu, Chen Shan, and 陳姍玗. "Development and ecological engineering aspects of azo-dye decolorization processes." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/02255587665757897828.
Full textAbstract:
碩士逢甲大學
化學工程學系
89
In this study, cells of Pseudomonas luteola, a bacterial strain capable of decolorizing azo-dyes, were entrap within gel matrix (calcium alginate (CA) and polyacrylamide (PAA)); the immobilized cells were utilized to remove the color of dye-containing wastewater. with fixed-bed processes. Repeated batch decolorization was also conducted to examine the operation stability and reusability of the immobilized cells. The effects of bed length, flow rate, and influent dye concentration on fixed-bed decolorization were studied. Ecological engineering aspects were introduced to investigate how interspecies interactions in mixed cultures affect microbial decolorization. The experimental results show that the fixed-bed columns packed with CA-immobilized cells of P. luteola allowed stable operation for 120 h with the addition of 0.01M CaCl2. PAA-immobilized cells have better mechanical stability, while CA-immobilized cells exhibit more efficient mass transfer and thus higher decolorization efficiency. With two 20-cm CA-immobilized cell columns operated in series, and with the influent dye concentration of 50 mg/L and flow rate of 30 ml/h., the decolorization rate was 1.14 mg/h. On the other hand, at the influent dye concentration of 200 mg/L and flow rate of 15 ml/h, columns with PAA-immobilized cells exhibited a decolorization rate of 2.82 mg/h. Since interspecies interaction occurred in mixed culture, the most ecologically favorable consortium for azo-dye decolorization was evolved. This study investigated interactions between decolorizers Pseudomonas luteola (species of A) and non-decolorizers Escherichia coli DH5α (species of B) to identify the optimal operation strategies for decolorization with the mixed culture. The results show that optimal conditions for decolorization were: dye concentration = 900 mg/L, pH = 5-7, and temperature = 28-42 ℃. The presence of DH5a enhances the decolorization efficiency of P. luteola even though DH5α was considered “ dormant” in this two-species community. The best decolorization rate occurred when the ratio of P. luteola and E. coli DH5α cells was 1:3. Supplement of extracellular metabolites of E. coli DH5α or E. coli NO3 can enhance the decolorization efficiency of P. luteola, especially for addition of metabolites of E. coli NO3, allowing P. luteola decolorize 200 mg/L of dye completely within 4 h.
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Wang, Yu-Min, and 王裕民. "Feasibility study of simultaneous dye decolorization and bioelectricity generation using indigenous dye-decolorizing microbes." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/41340654290072260347.
Full textAbstract:
碩士國立宜蘭大學
化學工程與材料工程學系碩士班
99
This study quantitatively explored interactive characteristics of simultaneous bioelectricity generation and dye decolorization (SBG&DD) in air-cathode single-chamber microbial fuel cells (SC-MFCs) using indigenous Proteus hauseri ZMd44. After approx. 15 cycles (ca. 30 days) of acclimatization in dye-bearing cultures, P. hauseri could express its stable capability of simultaneous bioelectricity generation (the maximal output voltage and decay rate were 137.0±3.0 mV and 1.20±0.01 d-1, respectively) and color removal (93–94% decolorization) in MFCs. Moreover, during acclimatization in same cultures the maximal output voltage of strains Enterobacter cancerogenus BYm30 and Enterobacter cancerogenus BYm30 were 185.5±3.8 mV, 179.7±0.5 mV and the decay rate wastants were 1.48±0.31 d-1, 11.1±2.1 d-1, respectively. Electrochemical impedance spectroscopy (EIS) was used to determine electrochemical characteristics of microbial fuel cell (MFC) based on Klebsiella pneumoniae ZMd31, indicating that the solution resistances decreased from 30.8 Ω to 23.7 Ω. Evidently, appropriate acclimation strategy to generate the electrochemically active anodic biofilm played a crucial role to enhance the performance of SBG&DD in MFCs. Gradually increased supplementations of C.I. reactive blue 160 resulted in progressively decreased decay rates of bioelectricity generation. That is, a dye decolorized in a faster rate would result in a lower capability for bioelectricity generation and vice versa. In addition, a reduced dye with less toxicity potency (e.g., 2-aminophenol, 2AP) might work as a mediator for electron transfer to anodic biofilm for bioelectricity generation in MFCs. The ranking of isomeric aminophenols for electron mediators in MFCs could then be shown as 2AP > 3AP > 4AP. Compare to other MFCs, Aeromonas or Klebsiella sp. seeding mixed culture MFC had better performance of SBG&DD. This study showed the promising SBG&DD of reactive blue 160 (RBu160) in SC-MFCs containing Exiguobacterium indicum NIU-K4 dominant microbes. Cyclic voltammograms (CV) and EIS findings also indicated that supplementation of RBu160 significantly augmented current production in the salty MFC.
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Liu, Shi-Qi, and 劉士琦. "Feasibility Study of Bioelectricity Generation and Dye Decolorization Using Microbial Fuel Cell." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/92976402617681906513.
Full textAbstract:
碩士國立宜蘭大學
化學工程與材料工程學系碩士班
101
This study tended to explore why and how some decolorized intermediates could play as a role of electron-shuttling mediator(s) to enhance capabilities of simultaneous reductive decolorization and bioelectricity generation in microbial fuel cells (MFCs). It also selected several model auxochrome-containing compounds to explore how chemical structure influenced the feasibility of electron-shuttling capabilities for power generation in MFCs. According to cyclic voltammetry, respiratory testing and MFC data, benezene-1, 2-diol (B12d) increased power-generating efficiency (PGE) of Proteus hauseri ZMd44 from 35.51 to 43.09 mW m-2, benezene-1, 4-diol (B14d) increased PGE of ZMd44 from 56.26 to 61.05 mW m-2, 1,2-diaminobenzene (12db) increased PGE of Aeromonas sp. C78 from 26.7 to 35.83 mW m-2, and 2-aminophenol increased PGE of Enterobacter cancerogenus BYm30 from 30.19 to 75.75 mW m-2. These all indicated that amino and hydroxyl groups are biochemically capable to enhance electron-shuttling capabilities. The findings clearly revealed that chemical structure of decolorized mediators directly affected characteristics of simultaneous reductive decolorization and bioelectricity generation in MFCs, suggesting optimal operation strategy of reductive decolorization using MFCs for wastewater treatment. This study also suggested that using microbial electrolysis cells is economically feasible for effective CO2 reduction.
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Chhabra, Meenu. "Decolorization/detoxification/degradation of textile dyes and dye wastewaters using cyathus bulleri laccase/laccase-mediators." Thesis, 2009. http://localhost:8080/xmlui/handle/12345678/2775.
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WU, HSIN-YI, and 吳欣怡. "Decolorization of Rhodamine B Dye by CuO Nanoparticles Synthesized by Quick Precipitation Method." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/nu38rz.
Full textAbstract:
碩士國立雲林科技大學
化學工程與材料工程系
105
Conventional methods for the preparation of CuO powders include one-step solid state reaction at room temperature, thermal decomposition of copper salts, mechanical milling of commercial powders, and so on. However, the dispersion of the nanometer CuO prepared by these methods is not good and forms an obstacle in many applications. Recently, some new synthetic methods have been developed for the purpose of obtaining good dispersion of nano-CuO. However, the equipment of these methods is expensive and the reaction conditions are harsh and require a large amount of organic solvent. In this study, highly dispersed nano-CuO in aqueous solution was prepared by simple quick-precipitation method and applied for catalytic degradation of Rhodamine B (Rh B). Using XRD and FTIR the as-prepared CuO was confirmed to have no other impurities, and TEM analyses revealed that it had a uniformly spherical shape with an average diameter of around 6.4 nm. From UV-vis absorption spectrum, the nano-CuO suspension was stable for up to 1 month and the band gap is estimated to be 3.01 eV. The feasibility of CuO/H2O2 system for catalytic degradation of Rh B was also investigated. Results demonstrated that at room temperature, 100 mL 10 ppm Rh B solution (pH 7) could be effectively degraded over 3 hrs by adding 1 mg CuO and 1 mL of 30% H2O2. Furthermore, the nano-CuO also showed a higher catalytic activity in Rh B degradation than other forms of CuO. This indicates that it may have a considerable potential on the applications in environmental chemistry and biotechnology.
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Lin, Meng-Yi, and 林孟毅. "Ecological engineering analysis for the assesment of bacterial consortium in azo dye decolorization." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/78916728875272202410.
Full textAbstract:
碩士國立成功大學
化學工程學系碩博士班
91
In this study, azo dye decolorization was used as a model system to investigate the correlation between population distribution and biological function in a mixed consortium from ecological engineering aspects. The approach may be extended to tackle the problems involved in practical biological treatment of wastewater. The bacterial decolorizer used in this study was Pseudomonas luteola, which decolorizes azo dye anaerobically, while preferably grows under aerobic conditions. Therefore, it is feasible to manipulate dissolved oxygen in the system to regulate cell growth and decolorization of the bacterium. In the analysis of ecological evolution of cell population, Lotka-Volterra competition equation was used to describe binary system, in which a decolorizer (P. luteola) and a non-decolorizer (Escherichia coli DH5a) coexisted. The results show that the competitive coefficient of Escherichia coli DH5a over P. luteola (a12)was greater than 3, while the competitive coefficient of P. luteola over E. coli DH5a (a21)was less than 1, suggesting that both strains inhibited each other when they were cultivated together and that the inhibitory effect of E. coli DH5a on P. luteola was stronger. This competition effect was also observed in the Replacement Series analysis under aerobic conditions. However, the replacement effect did not occur under anaerobic conditions, as the two strains evenly distributed in the anaerobic culture. This implies that the dissolved oxygen is a critical factor for ecology evolution of the binary bacterial system. The results also show that overall decolorization rate (ODR) of the binary decolorization process varied with the “population ratio” and “population size” of the two species. The optimal ODR (12.6 mg dye/L/h) occurred when the cell concentration of P. luteola and E. coli DH5a was 0.85 x 109 and 0.86 x 109 cell/ml, respectively. Thus, ecological environment can be adjusted or acclimated to achieve an optimal community function. In addition, this study also investigates the ecology evolution of the binary system in continuous mode with sequential shift-up and shift-down of the dilution rates. The result shows that the bacterial evolution was quite different in the presence or absence of the azo dye. The cell population distribution was irreversible at the same dilution rates during shift-up and shift-down processes. The information obtained from this work is expected to provide a simplified and feasible approach to evaluate the interrelation of the community structure and community function of a complicated wastewater system in order to locate an optimal operation condition for biological treatment.
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Yeh, Mao-Song, and 葉茂淞. "Kinetic Studies on Azo Dye Decolorization with Wild-type and Recombinant Bacterial Strains." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/74651185079932161803.
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碩士逢甲大學
化學工程學所
90
Abstract Azo dyes (C.I. Reactive Red 22; RR22, C.I. Reactive Black B; RBB and C.I. Reactive Acid Yellow 72; RAY72) were decolorized by a locally-isolated bacterium (Pseudomonas luteola), an Escherichia coli mutant (E. coli NO3) and a recombinant strain (E. coli CY1) harboring decolorizing genes from Rhodoccocus sp. Decolorization kinetics and operation stability of the strains were characterized quantitatively by repeated batch processes and an modified continuous-flow stirred-tank reactor (CSTR) to assess its feasibility in practical application for color-removal of dye-containing wastewater. The three bacterial strains were unable to decolorize RAY72 effectively due to its high bio-toxicity, while biosorption of RAY72 by the bacterial mass occurred. Decolorization of RBB by P. luteola was inefficient with only 65% conversion, while the color-removal efficiency exceeded 90% for the two E. coli strains. The NO3 and CY1 strains have similar maximum specific decolorized rate (85 mg dye g cell-1 h-1) when RBB concentration reached 1500 mg l-1 for NO3 and 1800 mg l-1 for CY1. This indicated that NO3 and CY1 could be operated in high RBB concentration. In addition, the specific decolorized rate of NO3 was more sensitive to variations in pH than CY1. Neutral and slightly basic pH values were favorable for RBB decolorization by the NO3 and CY1 strains. The specific decolorization rate increased as the temperature rose, until a sharp decrease occurred when the temperature exceeded 37 and 45oC for CY1 and NO3, respectively. A dissolved oxygen (DO) level of 0.35 mg l-1 or above appeared to significantly inhibit the activity of azoreductase for both NO3 and CY1 strains. E. coli NO3 was more stable than CY1 during repeated operations. For the mixed-dye (RR22 and RBB) system, the color-removal efficiency exceeded 90% for P. luteola and E. coli NO3 strains. The decolorization activity of P. luteola was better than that of NO3 and could operate at higher dye concentrations. The maximum specific decolorized rate was 38000 ADMI g cell-1 h-1 and 8900 ADMI g cell-1 h-1 for P. luteola and E. coli NO3, respectively. The specific decolorized rate of NO3 was also more sensitive to pH changes than P. luteola. Slightly basic pH values were favorable for mixed dye decolorization by P. luteola and NO3 strains. In addition, when the temperature exceeded 43oC, the decolorization efficiency of P. luteola and NO3 began to descend. The dissolved oxygen (DO) level of 0.35 mg l-1 or above also led to inhibit decolorization of the mixed dye by P. luteola and NO3 strains. The results indicate that the P. luteola and E. coli NO3 strains hold excellent reusability and persistence in repetitive decolorization operations. An anaerobic-aerobic intermittent CSTR process was used to decolorize mixed dye with E. coli NO3 strain at a hydraulic retention time (HRT) of 32, 18, and 10 h. The color-removal efficiency was around 70 ~ 80%. Under steady operation for over 117 h, the total decolorization was 10900, 18200, and 7590 (ADMI × L) for HRT=32, 18, and 10 h, respectively. After repeated operation cycles, the decolorization rate of E. coli NO3 was always higher than the original cycle. This may be attributed to the acclimation effect since the E. coli NO3 cells were repeatedly exposed to the azo dye.
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Tan, Chung-En, and 譚仲恩. "Synthesis of Pt/g-C3N4/SrTiO3 Photocatalyst for Simultaneous Dye Decolorization and Hydrogen Production in Simulation Dye Wastewater." Thesis, 2019. http://ndltd.ncl.edu.tw/cgi-bin/gs32/gsweb.cgi/login?o=dnclcdr&s=id=%22107NCHU5087020%22.&searchmode=basic.
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碩士國立中興大學
環境工程學系所
107
In this study, Pt/g-C3N4/SrTiO3 photocatalyst was applied to decolorize dye and produce hydrogen simultaneously. Firstly, the effect of calcination temperatures of g-C3N4 on dye decolorization efficiency was investigated. The optimal calcination temperatures of g-C3N4 was combined with commercial SrTiO3 in different ratio, and the composite with the best ratio was decided by activity test. Then the g-C3N4/SrTiO3 photocatalyst was coated with Pt metal, and the effect of different TEOA concentration on activity test, determining the optimal operating condition. The results showed that the degree of crystallization and thermal condensation of g-C3N4 were influenced by calcination temperature greatly. In addition, different calcination temperature also affected optical properties and photocatalytic efficiency and the yield of g-C3N4. The combination of g-C3N4 and SrTiO3 could change the transfer path of photo-generated charge. The results indicated that the g-C3N4/SrTiO3 photocatalyst belonged to Z-scheme semiconductor in this study. To retard the charge recombination rate of the g-C3N4/SrTiO3, coating Pt on the surface of g-C3N4/SrTiO3. The results indicated that the AR1 decolorization was further improved from 19% to 99% after adding 5% TEOA into the reaction. Because the TEOA in the reaction solution could effectively retard the charge recombination rate of photocatalyst, resulting in increased photo-generated electron-hole pair separation, and more photo-generated electron could reduce oxygen to generate •O2—. According to the results of activity test, Pt/g-C3N4/SrTiO3 photocatalyst optimal AR1 decolorization rate and hydrogen production rate respectively achieved 93% and 470 μmol h-1 g-1 when the AR1 concentration and TEOA concentration were respectively controlled to 50 mg/L and 25%. when TEOA concentration was controlled at 5% TEOA, the hydrogen production rate reached 102 μmol h-1 g-1 per ml of TEOA, which has the highest hydrogen production efficiency.
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Yueh, Pei-Lin, and 岳沛林. "Study of stimulating strategies of electron-shuttles for microbial bioelectricity generation and dye decolorization." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/05158621762355591472.
Full textAbstract:
碩士國立宜蘭大學
化學工程與材料工程學系碩士班
104
This feasibility study isolated indigenous functioning microorganisms from deep seawater (DSW)-fed Babylonia areolata for microbial fuel cell (MFC)-assisted dye decolorization (DD). Synergistic or antagonistic interactions of decolorized metabolites (DMs) on DD and bioelectricity generation (BG) in salty environment were also explored in depth. The rationale of study could be divided into three portions: (I) treatability study of microbial DD and BG was implemented by Shewanella sp. isolated from gut microbial consortia of DSW-fed B. areolata which was harvested from Hualien, Taiwan. Regarding screening protocol, as electron transfer (ET) mechanism for DD and BG were all associated, acclimation in dye-laden salty media was conducted for isolating bacteria with promising capabilities of DD and BG. The reasons why nanowire-generating Shewanella sp. WLP72 could be obtained herein were (1) specific gut microbial consortia in DSW-cultivated B. areolata provided critical selection pressure to maintain ecology likely not commonly present in wild nature; (2) low temperature at ca. 4C might exclude originally predominant bacteria in gut consortia to specifically isolate new functioning bacteria. The findings indicated that with serial acclimation under dye-bearing conditions Shewanella haliotis WLP72 expressed excellent dye-decolorizing performance, still maintaining stable azo-reducing capabilities in salt-laden cultures. Regarding portion (II), characteristics of BG and DD for DMs-supplemented cultures of WLP72 versus Exiguobacterium sp. K2 and Proteus sp. ZMd44 were significantly affected by chemical structure of DMs to be mediated. For example, -OH and -NH2 substitute-containing electron shuttles (ESs) were superior to dihydroxyl substitute-bearing ESs. Moreover, para-isomeric ES was apparently better performed than ortho-isomeric ES. Considering portion (III), to provide simple and plausible assessment to quantitatively evaluate ET efficiency in MFCs, this study also proposed “ET equivalent” concept, indicating “stoichiometric” equivalent electron number required to decolorize 1 g of azo dye in various conditions of SBG and DD. In fact, MFC-assisted DD increased overall ET efficiency more than 60%. Although the performance of SBG&DD reduced 40% in salty conditions, augmentation of DMs could overcome such hostile stress, resulting in >50% increase of overall performance. In summary, supplemented DMs could provide effective and feasible alternatives to overcome salty hostile conditions and significantly increase performance of BG and DD in MFCs for promising feasibility without dispute.
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Wu, Chun-Ming, and 吳浚銘. "Biosynthesis of Muconic Acid and Decolorization of Azo Dye by Sphingobacterium sp. and Mutants." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/13111177818348914420.
Full textAbstract:
博士輔仁大學
化學系
93
The annual global demand for adipic acid exceeds 2.2x109 Kg, which is primarily used in production of nylon-6,6. Industrial production of adipic acid is a premier example of synthetic methodology used on a mass scale that is not compatible with public environmental expectations and environmental policies of the 21st century. In this study, an environmentally compatible synthesis route has been established using a microbial strain to enzymatically convert benzoates into cis, cis-muconic acid. Subsequent catalytic hydrogenation of the cis, cis-muconic acid affords adipic acid. The bacterium strain has been identified to be a strain of Sphingobacterium sp., as confirmed by FIRDI (Food Industry Research and Development Institute) in Taiwan, and is assigned as a GCG strain by our lab. This GCG strain can produce about 101 mg/l of cis, cis-muconic acid in 62 h. It seems reveal that this strain follow the succinic CoA pathway for carbon source to enter into the TCA (Tricarboxylic Acid) cycle. In addition, two mutant strains, M4113 and M4115, are developed from the wild GCG strain by blocking the muconate-lactonizing enzyme via mutagensis induced by NTG (N-methyl-N'-nitrosoguanidine) and UV irradiation. A 10.5-fold and 5.5-fold increases in the yield of cis, cis-muconic acid are obtained for M4113 and M4115, respectively. On the other hand, a 4.2-fold and 3.3-fold increases are observed with GCG and M4115 strains when proceeded under fed-batch fermentation conditions. Furthermore, with the purpose of improving the activity of catA (catechol 1,2-dioxygenase), which is a necessary enzyme in this muconic acid producing metabolism pathway, EDTA-FeCl3 complex was employed in the culturing medium. It is found that an increment of 218 % and 43% of cis, cis-muconic acid are obtained for GCG and M4115 strains, respectively. Further studies show that some decolorizing strains can be produced from Sphingobacterium sp. and its mutant strains by proper training operation, These decolorizing strains, Azo-01, Azo-M1 and Azo-M2, can decolorize some commercial dyes used quite commonly in ordinary local dying factories. This study shows these strains exhibit some maximum specific decolorizing rate of 54.2, 75 and 73.86 (mg dye/ g cell/ h), respectively with Reactive Orange 16 dye in a concentration of 1.0 g/l. An anaerobic-aerobic intermittent CSTR process was used to decolorize Azo dye with Azo-M1 at a hydraulic retention time (HRT) of 8 h. The color-removal efficiency was around 85%. Under steady operation for over 60 h, the total decolorization capability could reach 1388.53 mg/l.
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陳麒鈞. "Decolorization of dye in wastewater by nanoscale zero-valent metallic particles immobilized cation exchange resin." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/00919009503403032195.
Full textAbstract:
碩士弘光科技大學
環境工程研究所
97
Wastewater streams from dyeing industries always carry complex characteristics such as high organic loading, high color intensity and seriously impact the water resources. The technologies such as coagulation and sedimentation, activated carbon adsorption, activated sludge treatment were used for dye wastewater treatment for a long time. However, those technologies were with their own limitations. Thus, to develop new integrated technologies became the major goal of research groups. Recently, there are some literatures present nano-scaled zero-valent Iron can treat dye wastewater with very good decolorization efficiency. But due to the nano-scaled particles are very difficult to handle which makes the scale-up very difficult. Therefore, the aim of this work is to utilize the ion exchange resin as the carrier of nano-scaled zero-valent metals to overcome the difficulties of nano-particle operation and reaches the higher treatment efficiency and ease to operate. Firstly, in this work resin carrying nano-scale metal were mixed with synthesized azo dye, Acid Blue 113, wastewater in a batch reactor. The operating parameters such as dye concentration, type of metal, dosage of nano-scaled metal, mixing speed and pH were investigated to verify the effects of operating parameters on decolorization. Secondly, a packed bed column reactor with resin carrying nano-scale metal packing was setup and tested. The operating parameters such as type of metal, ratio between bimetallic materials were tested to observe the effects on decolorization. Furthermore, the regeneration and reuse of spent resin carrying nano-scale metal for decolorization were investigated. The results showed that resin with nano-Iron coating performed better decolorization efficiency than other metals. In thirty minutes of reaction time, the color was almost removed by nano-Iron coated resin. Higher initial dye concentration caused low color removal efficiency and higher metal dosage can reach higher removal efficiency. The operating pH affected decolorization significantly. Under extreme pH conditions such as pH 2 and pH 12, the decolorization reaction were inhibited, the final removal efficiencies were 28.5% and 21.1% for pH 2 and pH 12, respectively. For mild condition, such as pH 9, a dye removal efficiency of 92% can be reached in 60 minutes of reaction time. For packed column experiments, resin coated with bimetallic performed better than single metal on decolorization. In defined operation conditions of this work, the exhaust volume of 5100 ml was obtained for bimetallic coating resin. To regenerate the nano-metal coated resin in packed bed column, the regeneration by 0.8 M NaBH4 solution for Iron coated resin received better regeneration efficiency. After regeneration, the Iron coated resin gained exhaust volume to 7600 ml. As for Nickel coated resin, it is better to use 0.1 M HCl to regenerate. The exhaust volume of regenerated Nickel coated resin was 5000 ml.
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Jer-Min, Lin, and 林哲民. "Decolorization of Reactive Dye Wastewater Using UV/H2O2 Ozonation and UV/O3 Advanced Oxidation Processes." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/84252950007283022996.
Full textAbstract:
碩士逢甲大學
環境工程與科學學系
89
The photochemically oxidative decolorization of wastewater containing with textile dyes was studied using a batch reactor. The chemical characteristics of dyes are pretty stable in the aqueous solution, therefore, the biological treatment methods are ineffective for decolorization of dye stuffs in the effluent stream. The other conventional wastewater treatment techniques, including ultrafiltration, chemical coagulation, adsorption, and solvent extraction are not very efficient in dealing with the dye wastewater. As the discharged regulations are becoming more stringent, consequently, the color removal in dye effluent is presently one of the most important subjects in pollution control. This study was conducted to investigate the degradation efficiency for treating reactive dyes in water solution using UV/H2O2, O3 and UV/O3 photochemical oxidation process. The photochemical oxidation is one of the advanced systems for wastewater treatment. This method involves the formation of hydroxyl radicals（·OH）in the aqueous phase through ultraviolet photolysis of hydrogen peroxide and ozone. Experiments were conducted to reduce the ADMI value of dye wastewater. Six commercial reactive azo dyes were chosen for this study. The kinetic aspects of the UV/H2O2, O3 and UV/O3 treatment processes were also evaluated for six reactive dyes. The experiment results showed that the UV/H2O2, O3 and UV/O3 process for a 500mg/L of dye solution, the color could be totally removed within 40 min under the studied condition. The H2O2 and O3 dosage may affect the color removal in a positive way. However, owing to the temperature effect of the ozone soluble, the photodegradation of the dye by UV/O3 was not very effective compared with that of O3 system.
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Hsu, Tzu-Ping, and 徐子平. "Effect of Iron Salt Types on Decomposition and Decolorization of Reactive Dye by Photo-Fenton Process." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/92615674789568508101.
Full textAbstract:
碩士淡江大學
水資源及環境工程學系
89
The type of iron salts is one of important operational variables in the photo-Fenton process. The ferric ions can be reduced to ferrous ion by UV photolysis. The ferrous ions react with hydrogen peroxide to occur the Fenton reaction. This study was to evaluate the decomposition and decolorization of a reactive dye by the Photo-Fenton process. The commercial available reactive dye, Blue 19, was employed to prepare the synthetic wastewater sample. The experimental variables studied include dosages of hydrogen peroxide and iron salts, and type of iron salts. All experiments were conducted by a batch photo reactor. Moreover, the sulfate ferrous and nitrate ferric were used iron salts. The residual color and dye was determined by the ADMI method and high performance liquid chromatograph (HPLC), respectively. The results show that the solubility of iron salts decreases with the increase of pH. The solubility of ferric increases in the presence of oxalate. The Fe(III)-oxalate is the predominant complex compound under acidic pH ranged from 4 to 6. Since the oxalate is a organic compound. It can compete hydorxyl radicals (OH·) with the dye and reduce the removal of color. The optimal oxidation time for the removal of color and dye was 5 min by the Ferrioxalate /H2O2/UV process. Due to the color-contained ferrous-dye complexes, the color resurgence was observed as the oxidation time more than 5 min. The color resurgence was significant at higher ferrous dosages. Furthermore, the color removal increases significantly with the increase of H2O2 dosage. The color resurgence was less at higher H2O2 dosage. In contrast, the color and dye was removed for reaction time only 1 min by the Fe2+/H2O2/UV process. The color resurgence does not occur during the reaction period. Comparing the removal of color and dye by these two processes, results indicate the Ferrioxalate/H2O2/UV process performs higher removal of dye and color than that by Fe2+/H2O2/UV process, in early reaction period. However, the Fe2+/H2O2/UV process has higher removal of color with a longer reaction time.
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Lin, Chun-Hui, and 林純卉. "Investigation of decolorization and degradation performance of textile dye by Aspergillus niger and Bacillus sp. coculture." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/843f3w.
Full textAbstract:
碩士國立臺北科技大學
生物科技研究所
98
This study explore the decolorization and degradation mechanism of textile dye, including reactive red dye HE3B (C.I. Reactive red 120) and direct green dye BB50 (C.I. Direct green B), through coculture of fungi and bacteria. After 24 hours cultivation, the decolorization efficiency of Aspergillus niger and Bacillus sp.was 50% and 30% respectively. However, the dye decolorization can reach 90% by using two strains coculture. Therefore, we designed Aspergillus niger and Bacillus sp. coculture model to enhance the performance of decolorization and degradation of dyes. In order to find the optimal result of coculture, and explore the importance of different independent factor in dye biodegradation, we use the response surface methodology to achieve quicker and higher degree decolorization. Preliminary results showed that elements of the composite culture medium, such as malt extract, glucose, KH2PO4 concentration displayed a statistical significance in dye decolorization. Through the response surface method, reactive red dye HE3B had 92.68% decolorization and direct green dye BB50 had 97.66% decolorization in case of 0.1% malt extract, 0.7% KH2PO4 and 0.8% malt extract, 0.5% glucose, respectively, after 2 hours culture. The chemical structure of decolorized residues had been analysised by HPLC. Based on the results, there are no any aniline compounds in the medium. Therefore, the aromatic structure had been destroyed in the decolorized procedure and did not produce any toxic components. Through immobilization of two strains on an insoluble substrate, the efficiency of decolorization can indicate higher efficiency and convenience. There exists a 3-fold better decolorization of immobilized mixed bacterial than the free state. So this strategy could be applied to wastewater treatment of textile plant for dye decolorization.
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JAM, SO MIN, and 簡守民. "Studies on the Decolorization of Dye Wastewater by Ozone and Oxidation of Cyanide in Aqueous Solution." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/66220934883791763088.
Full textAbstract:
碩士逢甲大學
化學工程研究所
83
An electrochemical system to improve the ozone current efficiency(C.E.) has been studied by selecting cell type and modification of anode. We found that the C.E. was decreased as the roating speed increased in the roating disk cell. On the other hand, dopped cationic and anionic surfactant did not increase C.E. significantly. For the oxidation of cyanide in aqueous solution by using lead dioxide as anode, we found that adding sodium chloride to the solution, which was in the pH range below 4 had good efficiency. For inavtivation of Pseudomonas aeruginosa PU21(Rip64) by ozone, we found that it had good efficiency and relationship of ozone concentration(c) and the contacting time(t) with the survival(S) could be expressed by the following :Ｃ×ｔ＝１.５Ｓ^（－０.４） Kinetic study on the decolorization reaction for ozone and direct dye 40215 ,we concluded that this reaction was mass transfer controlled and was a direct oxidation. The rate equation could be expressed by the following:the kinetics of the reaction was first order with respect to ozone and 0.89 order with respect to dye. The rate constant(K) was 8.06*10^7 and activated energy was 8.4 Kcal/mol-K. The stoichiometric for ozone and dye is "3". Kinetic studies on the decolorization reaction for ozone and dispersed dye 11110, we concluded that the activated energy is 9.856 Kcal/mol-K.
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Wu, Min-Xun, and 巫旻勳. "Study of the Decolorization Effect on Enzyme Derivatives-Hydrogen Peroxide System with Ion Red Dye Waste Liquid." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/b26q94.
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Liu, Bo-Wen, and 劉博文. "Effect and Economic Analysis on the UV/Ozone Decolorization of a Dye-finishing Wastewater and Commercial Dyes – Reactive Orange 13 and Blue 19." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/84610497952915329408.
Full textAbstract:
博士國立中山大學
環境工程研究所
92
Currently in Taiwan’s textile-dying industry, sodium hypochlorite (NaOCl) is popularly used as a decolorization oxidant. In order to surely meet the effluent color regulation of 550 ADMI (American Dye Manufactures Institute), excessive dosage of sodium hyperchlorite is commonly used, which results in the increase of residual chloride and the accumulation of toxic chlorinated compound in the environment. This study probes into the characteristics of substitute oxidant for sodium hypochlorite to avoid the production of toxic products. The study includes decolorization efficiency evaluation, economical analysis and feasibility of commercial application. This study adopts ozone as an oxidant and ultraviolet light as the oxidant enhancer for the purpose of preventing the occurrence of secondary pollution products like trihalomethane from the sodium hyperchlorite application. Literature review indicates that there are several studies for reaction mechanisms of oxidation and disinfection of ozone and ultraviolet light for decolorization and the conclusions reveal much promising results. There are three topics in this study, which are: Topic 1: Feasibility study. This study focuses on whether the effluent color concentration of the treatment process meets the color effluent standard or not. A 3.5 L volume reactor was used in this section. Topic 2: Influencing factor analysis. A 14 L volume reactor was adopted for analyzing the influencing factors for decolorization and for comparing the differences in treatment efficiencies between a dye finishing plant effluent and two commercial dyestuff samples. Topic 3: Economic analysis. The analysis focuses on economic comparison between NaOCl and UV/Ozone processes for effluent decolorization. Analysis results of the investment cost, operation/maintenance expense, and investment return duration are presented in this section. A 50 L volume reactor was used to achieve the evaluation for this part. First topic of this study examined some operating parameters for treating effluent from the biological and chemical coagulation units of a dye-finishing wastewater treatment plant using the UV/Ozone technique to meet an effluent regulation of 550 ADMI values could be reduced from approximately 4,000 to 200 ADMI in an hour using the UV/Ozone technique. The results show that higher color removal efficiency could be achieved at pH values around 3 as compared with higher pH values of around 7 and 10. This might be due to the fact that the predominant ozone molecules at lower pH values are more selective to certain chromophore molecules in wastewater, despite the fact that hydroxyl radicals are predominant at higher pH values and have a stronger oxidation capability than ozone. The UV light used in this study emitted from the experimental lamp can excite oxygen and water molecules to produce ozone molecules and hydroxyl radicals that can then increase decolorization rate. The findings of this investigation reveal that the proposed UV/Ozone treatment scheme has potential for development into an environmentally friendly decolorization approach for dye finishing wastewater treatment. The second topic is to investigate the feasibility of applying UV/Ozone techniques to reduce color content caused by two commercial reactive dyes (Orange-13 and Blue-19). Bench experiments were performed using a 14-L reactor. Controlling factors including pH value, dosage of ozone, reaction time, and UV intensity were evaluated to obtain the optimal operating parameters. Results from this study show that the ozone dosage and pH value dominated the effects on the decolorization process. However, UV intensity shows relatively insignificant effects. Results also indicate that the color content could be reduced from 2,000 to 200 ADMI within a reaction time of 30 minutes with a total ozone dosage of 100 mg/L. This study shows that pH values of approximately 3 and 10 favored the decolorization of the studied Dye Blue-19 and Orange-13, respectively. This was due to the effects that molecular ozone and hydroxyl radicals had significant oxidative power at low and high pH, respectively. Moreover, molecular ozone was more selective to certain dye structures during its oxidation process. This also caused the effect that pH value played an important role on color removal. Kinetic analyses show that the decolorization reactions of Dye Orange-13 and Blue-19 followed a first-order decolorization model. Experimental results also indicate that the degree of decolorization was primarily proportional to the ozone dosage. Results from this study provide us an insight into the characteristics and mechanisms of decolorization by UV/ozone technique. Results will also aid in designing a system for field application of dye finishing plants. According to the results from the third topic, for a dye finishing plant of wastewater flow rate of 800CMD (m3/day), the capital cost of equipment and related establishment as well as amendment is about US$ 116,300, and the monthly operation and maintenance cost is US$ 4,030. In this study, ozone was used as a substitute decolorizing oxidant to treat the effluent from the secondary biological and physical/chemical treatment plant. Because the current cost for the decolorization oxidant (NaOCl) is approximately US$ 5,700 per month, the monthly saving, adopting the decolorization system using UZ/Ozone, will be US$ 1,670. The investment return period will be over 7 years and is not attractive to the plant owners. However, to prevent the accumulated toxicity of chloride compounds in the environment and to promote the desires of investment on the advanced decolorization technique, a favorable tax deduction policy needs to be applied.
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Zi-Yao, Zhou, and 周子耀. "Effects of Strains and Media on Activities of Ligninolytic Enzymes and Decolorization Treatment for Dye Waste Water by Trametes versicolor Submerged Fermentation." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/35636967462303004671.
Full textAbstract:
碩士大葉大學
生物產業科技學系
101
Trametes versicolor is a medicinal fungus, also known as white rot fungi. T. versicolor contains multiple extracellular enzyme systems that degrade organic matter in the environment, especially lignin., The biodegradable matters were then used for mycelial growth, by secreting laccase (laccase; EC1.10.3.2), manganese peroxidase (EC 1.11.1), xylanase (EC 3.2.1.8) during the fermentation processes. Those enzymes showed effects on lignin degradation, however, different T. versicolor strains isolated from Taiwan showed different lignin degradation activities. In the fermentation processes, the compositions of fungal culture medium is very important, the agricultural nutrient sources in the medium are more complex than chemical medium. Many pevious reserches replaced half of culture medium with agriculture compartments to increase the fungal metabolites such as fungi polysaccharides. In this thesis, Taiwan strains T. versicolor BCRC35644, BCRC35759, BCRC35682, BCRC 35683 and LH1 were tested for multiple enzyme activities using differet fermentation mediums. As for the laccase activity in liquid fermentation comparisons, the results of chemical medium were 23U/mL, 35U/mL, 61U/mL, 76U/mL, 37 U / mL, respectively. As for the laccase activities in agricultural medium, were 81 U / mL, 69 U / mL, 282 U / mL, 188U/mL, 342 U / mL, respectively. Phenol blue agar was then used to exam the manganese peroxidase avtivities of LH1 and BCRC35682. The results showed that T. versicolor LH1 has a better manganese peroxidase activity. To further explore the manganese peroxidase activity of T. versicolor LH1 in fermentation processes, T. versicolor LH1 was subjested used in a fermentor. The result showed that in the highest manganese peroxidase activity was obtained in the first six days with the activity of 36.654U/mL, highest xylanase activity was also obtained during the first six days with the activity of 2.5U/ml. Bleaching experiments were carried out by adding clothes dyes to the diluted culture medium to explore the free agent mycelium decolorization ability, the result showed that free mycelia decolorization capacity can up to 95%. Finally, T. versicolor LH was used on different stages of processed dying waste water to test for its decolorization abilities, the results showd that T. versicolor LH had a good decolorzation ability. The experimental results show that agriculture medium can increased laccase activity by 2 to 10 times higher than chemical medium. The highest activity of manganese peroxidase, xylanase were also obtained during the first six days of culture. T. versicolor LH1 also showed good performance on bleaching activity. This thesis provides valuable results for industrial applications, in the future, with the improvement of the enzyme purity, laccase from T. versicolor LH1 in wastewater treatment will be very valuable and significance.
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Cheng, Hsu-Hui, and 鄭旭惠. "Preparation of N-doped TiO2 Nanocatalysts by LPNTP Technique for Decolorization of Azo Dye with the Catalyst Separation/Recovering System using Ceramic Membrane." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/3mxg86.
Full textAbstract:
博士國立臺北科技大學
工程科技研究所
100
Yellow-colored N-doped TiO2 (TiOxNy) powders, synthesized by the liquid-phase non-thermal plasma (LPNTP) technique, were produced from a mixed aqueous solution, containing commercial titanium dioxide (Degussa P-25) and an N-precursor (ammonium chloride, NH4Cl), and utilized for photodegradation of C. I. Acid Orange 7 (AO7) under visible light. The benefit of such technology is mainly on rapid production of visible light photocatalyst N-doped TiO2 under room temperature and pressure. A high voltage applied to the electrodes was to generate a strong and transient electric field, and the discharge emit ultraviolet light of sub-critical wavelengths was used to illuminate TiO2 producing electron-hole pairs by exciting electrons from the valance band to the conduction band. These promote the replacement of O atoms with N atoms to narrow the band gap of photocatalyst. To enhance the photocatalytic efficiency of TiOxNy under visible light, this study also developed a new continuous-flow photoreactor by further combining a UF ceramic membrane system to recover the TiOxNy particles in the suspension system. The recovered TiOxNy particles were subjected to repetitive cleaning and reuse. This not only complies with the practices of green technology and energy, but also achieves the aim of "zero waste". The TiOxNy photocatalysts obtained through the LPNTP process were characterized with UV-Vis spectrophotometer, XRD, ESCA, TEM, and EDS, respectively. The UV-Vis spectrum of N-doped TiO2 showed that the absorption band was shifted to 439 nm and the band gap was reduced to 2.82 eV. The structure analysis of XRD spectra showed that the peak positions and the crystal structure were changed by plasma-treating at 14.1 W for 40 min. In the batch photocatalytic system, ninety percent of azo dyes were degraded under visible light irradiation for 10 hours in the optimum condition of TiOxNy-1:6. Furthermore, a screening effect of excess particles was observed when the dosage of TiOxNy-1:6 was over 0.2 g/L, and an optimum dosage of TiOxNy-1:6 at 0.15 g/L was determined. Additionally, the optimal conditions for preparation of the photocatalyst as TiOxNy-1:6 was chosen to perform the photocatalytic activity and durability test in a continuous-flow photocatalysis/membrane separation system (PMSS). The experimental results showed that the optimal dosage of TiOxNy was 0.5 g/L, and the AO7 degradation efficiency was effectively improved by increasing oxygen concentration from 0% to 40% or decreasing the initial AO7 concentration from 15 to 5 mg/L. The degradation efficiency of AO7 increases as pH decreases, exhibiting a maximum efficiency at pH 2. For membrane separation/recover system, the recovery efficiency reached 99.5% after the ultrafiltration had been carried out for 90 min, and the result indicated that the photocatalyst was able to be separated/recovered completely. For this reason, the photocatalyst was recovered completely. The durability of the photocatalyst was evaluated by reusing the photocatalyst 11 times and the recycled catalyst was capable of repeating 5 runs without significant decrease in treatment efficiency. In addition, the durability of TiOxNy catalysts with aeration, which decreases catalyst deactivation, was longer than that without aeration.
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"Decolorization and biodegradation of methyl red by acetobacter liquefaciens." Chinese University of Hong Kong, 1989. http://library.cuhk.edu.hk/record=b5886177.
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Wang, Mei Huey, and 王美惠. "Decolorization of Azo Dyes by White Rot Fungi." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/87834103007768891264.
Full textAbstract:
碩士東吳大學
微生物學系
83
The capacities of various white rot fungi to decolorize serveral azo dyes, mainly Orange G, were studied in the pre- sent study. Among 15 different isolates, isolate 7 showed the best decolorization ability, which could remove 93% of the added dye in 2 hours. When isolate 7 was precultured in media buffered differently(i.e., potassium phosphate、sodium acetate and DMS buffered medium), the highest dry weight was obtained in potassium phosphate buffered medium. But, we failed to de- tect any significant of its decolorization activity. On the other hand, different medium compositions do show the effect on the decolorization ability of various white rot fungi. But we did not observe positive correlation between decolorization ability and the amount of fungi biomass been produce. When studying the effect of pH, the best decolorization activity was observed between 5 and 6. The effect of medium composition on the production of Laccase, Lignin per-oxidsae, Manganese dependent peroxidase, and Glyoxal oxidase was also studied. Regardless, whether it is in the filtrate or on the hyphae,the highest enzymatic activities were always detected when 1/2 PDB was used as the cultural medium. Unfortunatelly, I was unable to detect a correlation between the decolorization ability of isolate 7 and the production of the above enzymes.
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Jane-Yii, Wu, and 吳建一. "The technology developments in microbial decolorization of dyes." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/jyk9um.
Full textAbstract:
博士國立清華大學
化學工程學系
90
Azo dyes are the largest class of dyes with a world market share of 60-70%. At least 3,000 different varieties of azo dyes are extensively used in industries for various purposes. Although the azo dyes do not generally display acute toxicity, they are regarded as water pollutants because of their high color intensity in the environment. Approximately 10-15% of the amount of synthetic dyes produced annually is discharged with factory aqueous effluents, and most dyes are resistant to degradation by traditional biological processes. In the past two decades, several physical or chemical decolorization techniques have been developed, but few of them are accepted by the industries. Their lack of implementation is due to a high cost. As a viable alternative, a novel biological process has received an increasing interest owing to their cost effectiveness and environmental benignity. The main aim of the research was to determine the feasibility of the combined methods using fluidized bed reactor with immobilized-cell beads in decolorization of azo dye. The description of this study is divided into five sections. The first section is focused on the evaluation of modified polyvinyl alcohol (PVA) immobilized technique in decolorization of textile dyes (Chapter 2). The results prove that the modified PVA immobilization technique has been successfully applied to the decolorization process in a continuous stirred tank reactor. The elasticity and high mechanical strength of PVA beads was also proven to be adequate for the high shear stresses encountered in the reactor. Microscopic observation revealed that the microbial consortium contained in the gel beads was at least made up of three kinds of bacterial species, i.e., circle-shaped bacteria, rod-shaped bacteria, and filamentous bacteria. The second section of this research, covered in two chapters (Chapter 3 and Chapter 4), deals with the isolation of the azo-degrading bacteria from the activated sludge of petrochemical plants and the mud of University Lake. The mechanism of dye degradation using the isolated strains and the factors affecting biodegradation of azo dyes were also investigated. Several bacterial strains with the capability of degrading textile dyes were isolated. Aeromonas hydrophila was selected and identified because it exhibited the greatest decolorization ability both in terms of extent and rapidity of decolorization for 24 kinds of azo, anthraquinone, and indigo dyes. Although A. hydrophila displayed good growth in aerobic or agitation culture, color removal was the best in anoxic or anaerobic culture. Dissolved oxygen (DO) concentration exceeding 0.45 mg l-1 inhibited significantly bacterial decolorization. Glucose inhibits bacterial decolorization activity because the consumed glucose was converted to organic acids that might decrease the pH of the culture medium, thus inhibiting the cell growth and decolorization activity. In addition, preliminary results indicated that decolorization proceeded primarily by enzymatic reduction associated with a minor portion of biosorption onto the inactivated microbial cells. The third section deals with the mass transfer phenomena and the degraded dynamics of azo dyes in the PVA immobilized-isolate beads (Chapter 5). The concentration of polymer and the density of the cell in the gel beads were the most significant influencing factors on dye diffusion at a negligibly external mass-transfer resistance condition. In addition, we have developed a procedure, which permit extraction of the intrinsic kinetic parameters from observed reaction rates. This method and concept may be used to analyze the performance of other immobilized-cell systems. On the other hand, the effectiveness factors of immobilized-cell beads have been calculated for a range of microenvironmental conditions and macroenvironmental conditions. The results showed that intraparticle diffusional resistance has a significant effect on the azo dye biodegradation rate. The calculated effectiveness factor (ηcal) approached unity at Thiele modulus (Φ) < 0.3 (dp < 0.475 mm). The only limitation was believed to be the enzymatic reaction. The internal diffusional limitations were neglected. The fourth section deals with the hydrodynamic behaviors of PVA immobilized-cell beads in the liquid-solid fluidized bed bioreactor (Chapter 6). Our new experimental results were presented and compared with published results for the drag coefficient-Reynolds number, velocity-voidage, and expansion index-Reynolds number relationships observed during fluidization of rigid particles in a fluidized bed. Predictions made from previous correlations were examined with our new experimental findings, revealing the inadequacy of most of these correlations. Thus, new correlations describing the above-mentioned relationships are suggested. For multiparticle systems, the correction factor, f(ε), was a function of the falling gel bead properties (Reynolds number) as well as the fluidized gel bead properties (Archimedes number), and depended strongly on the bed voidage (ε). A new simple relation was developed to predict easily theεvalue from 0.5 to 0.9 at 4986< Ar < 40745. The experimental results may also be used to analyze the hydrodynamic performance of other various entrapped materials in liquid-solid fluidized bed bioreactor (FBR). The final section deals with the operational performances and modeling study of the liquid-solid FBR using immobilized-cell beads on decolorization of azo dye. The hydrodynamic characteristics of particles (Chapter 6) and the internal diffusional limitations (Chapter 5) were taken into account (Chapter 7). It was found that azo dye degradation time initially reaching a steady state decreased with an increase in bed expansion, cell bead number density and hydraulic retention time (HRT). The mean cell residence time (θC) on liquid-solid FBR using PVA immobilized-cell beads increased insignificantly from 1014.1 to 1014.9 days as the HRT increased from 3 to 24 h, and thus the impact of conventional reducedθC can be minimized by using the same polymer as support carries. Additionally, the internal mass-transfer resistance rather than the film diffusion resistance played an important role in azo dye utilization in liquid-solid FBR when film modulus (mf) was smaller than 1. On the other hand, the model was validated through the comparisons with the experimental data that the azo dye biodegradation was at a steady state under well-mixed operating conditions. The results also showed that the model was close enough to be used in the design and simulation of liquid-solid FBR operated with immobilized-cell bead system.
48
Hua, Du Chia, and 杜佳樺. "Decolorization of synthetic dyes in aqueous solutions by fungi." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/61752421465920254213.
Full textAbstract:
碩士中華科技大學
健康科技研究所
103
Microbial decolorization is an unexpensive and adaptable process to reduce the synthetic dyes of water pollution. In this study, white rot fungi and Penicillium notatum were used to remove methyl red, methylene blue and methyl violet dyes from aqueous solutions. The effects of contact time, temperature and initial dyes concentration on dye removal efficiency were investigated. Results of biosorption experiments via dead fungal biomass showed that the removal efficiencies of methyl red, methylene blue and methyl violet dyes were fitted to the Freundlich and Langmuir isotherm models. The maximum biosorption capacity of white rot fungi and Penicillium notatum for methyl violet was found to be 299.3, 32.6 and 29.5 mg/g in 3 days, respectively. Degradation of methyl violet by live Penicillium notatum was assessed. At the end of 8 days of incubation，over 40％ of methyl violet was degraded by the fungal treatment in liquid medium．This work demonstrates that the microbial decolorization had a potential to be used in the removal of synthetic dyes from aqueous solutions.
49
張坦卿. "Decolorization of reactive dyes by phanerochaete chrysosporium in agitated cultures." Thesis, 1991. http://ndltd.ncl.edu.tw/handle/42829504280950711187.
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50
Chen, Ya-Ting, and 陳雅婷. "Decolorization of Synthetic Dyes by immobilized Laccase from Ganoderma tsugae." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/49703792131098582817.
Full textAbstract:
碩士環球科技大學
生物技術研究所
101
Laccase which could be found basically in white-rot fungi and catalysis the oxidation-reducation reaction of phenolic compounds is one kind of polyphenol oxidase. It includes many kinds of oxidation matrix, such as phenols and the deriviates, alkylaniline, alkylaniline derivatives, aromatic carboxylic acid, aromatic carboxylic acid derivatives and so forth. Laccase could be used to remove pollutants toxins of industrial waste water then purify waste water, to be used to bleach pulp and change chemical properties, to be used to decolor dyes of textile products, to be used to decompose chemical compounds of feticide and pesticides, to be used to produce Biological Catalyst of anti-cancer medicines or be used to as additive of cosmetics and so forth. The most important obstacles to commercial application of laccases are the lack of sufficient enzyme stocks and the cost of redox mediators. In this research we used culture medium for laccase production from Ganoderma tsugae G924 was optimized and decolorization effects test of immobilization laccase according to the results of single factor tests three factors and three levels were analyzed by response surface methodology and the second-order equation model was established by regression analysis of experimental data. The predicted optimal addition of temperature,pH and inducer Monosodium glutamate was 29℃,pH 4.5 and 0.7 g/mL respectively, and the predicted maximum laccase could reach to 81 U/mL. The laccase activity of verification experiment was 83.57 ± 3.97 U/mL, which was very close to the predicted value. The laccase activity under the optimization condition increased 10.8 times as compared as to the original enzyme production medium. In this study, we used chitosan-alginate and polyvinyl alcohol-alginate as the matrix for laccase immobilization for further study. In the thermal stability test, our results showed that both of the immobilized laccase could undergo more than 5 times repeated use with 50% residual activity retained. According to the results of synthetic dye decolorization test, we found that the rate of decolorization of chitosan-alginate and polyvinyl alcohol-alginate immobilized laccase in 2 hours under the temperature of 60℃ were 15.77 % ~ 87.56 % and 72.92 % ~ 91.80 %, respectively. To the best of our knowledge, this is the first report that immobilization of laccase from Ganoderma tsugae G924 with chitosan-alginate and polyvinyl alcohol-alginate. These results demonstrated a promising future of applying immobilized laccase for industrial synthetic dye decolorization.