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Potential of a fungus, Acremonium sp., to decolorize pulp mill effluentLesley, Dawn 03 June 1993 (has links)
This project explored the feasibility of using fungi in a constructed wetland
for the treatment of pulp mill effluent. The effluent is high in dissolved
lignins (some of which are chlorinated), which have proven very difficult to
degrade biologically. Mindful of work done with the (terrestrial) white rot
fungi, especially Phanerochaete chtysosporium, the question is asked, Is there
a fungus which can tolerate submerged conditions while degrading a
significant amount of dissolved lignins? Two fungal species with lignin-degrading
capability were isolated from submerged films in a log pond.
These fungi have been evaluated for decolorization potential under different
environmental conditions.
Results of laboratory experiments show that one of these fungi, identified as
Acremonium sp., was capable of 44% decolorization of pulp mill effluent
under sterile, submerged, room temperature conditions. The fungal
decolorization was evaluated both in floating cultures and as a film
inoculated on wood chips. In addition, bench-scale examination of the
potential of this fungus to decolorize pulp mill effluent in non-sterile
conditions was completed. / Graduation date: 1994
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Enhancement of chemical degradation of synthetic dyes by biosorption.January 1998 (has links)
by Stephen, Man-yuen Cheng. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 124-141). / Abstract also in Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / List of Figures --- p.iv / List of Tables --- p.ix / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- The development of dyes --- p.1 / Chapter 1.2 --- The chemistry of azo dyes --- p.2 / Chapter 1.3 --- "Evaluation of dyes submitted under the ""Toxic Substances Control Act"" new chemicals programme" --- p.6 / Chapter 1.4 --- Environmental concerns of dyes --- p.7 / Chapter 1.5 --- Decolorization techniques --- p.11 / Chapter 1.5.1 --- Activated sludge process --- p.11 / Chapter 1.5.2 --- Chlorination --- p.12 / Chapter 1.5.3 --- Fenton's reaction --- p.13 / Chapter 1.5.4 --- Ozonation --- p.13 / Chapter 1.5.5 --- Adsorption by activated carbon --- p.13 / Chapter 1.5.6 --- Chemical flocculation --- p.14 / Chapter 1.5.7 --- Coagulation --- p.14 / Chapter 1.5.8 --- Advance Oxidation Process --- p.15 / Chapter 1.5.8a --- Photocatalytic activation --- p.17 / Chapter 1.5.8b --- Enhancement of reaction rates of photocatalytic reaction --- p.21 / Chapter 1.5.9 --- Biosorption of azo dyes by Pseudomonas sp. K-l --- p.23 / Chapter 1.6 --- Water pollution in Hong Kong --- p.24 / Chapter 1.7 --- Purpose of study --- p.24 / Chapter 2 --- Objectives --- p.27 / Chapter 3 --- Materials and Methods --- p.28 / Chapter 3.1 --- Materials --- p.28 / Chapter 3.1.1 --- Azo dyes --- p.28 / Chapter 3.1.2 --- Biosorbent --- p.28 / Chapter 3.1.3 --- Chemicals --- p.28 / Chapter 3.2 --- Photocatalytic reactor --- p.31 / Chapter 3.3 --- Determination of the peak absorbance of five azo dyes at different pH --- p.31 / Chapter 3.4 --- Determination of dye concentration by measuring at peak absorbance --- p.37 / Chapter 3.5 --- Determination of pseudo-first-order rate constant --- p.37 / Chapter 3.6 --- Effect of initial concentration of procion red MX-5B on photocatalytic degradation --- p.39 / Chapter 3.7 --- Effect of initial concentration of hydrogen peroxide on photocatalytic degradation of procion red MX-5B --- p.40 / Chapter 3.8 --- Effect of initial pH on the photocatalytic degradation of procion red MX-5B --- p.40 / Chapter 3.9 --- Effect of initial temperature on the photocatalytic degradation of procion red MX-5B --- p.40 / Chapter 3.10 --- Effect of titanium dioxide on the photocatalytic degradation of procion red MX-5B --- p.40 / Chapter 3.11 --- Effect of UV intensity in the photocatalytic degradation of procion red MX-5B --- p.41 / Chapter 3.12 --- Degradation kinetics of different dyes --- p.41 / Chapter 3.13 --- Degradation of 40 mg/L of procion red MX-5B under optimized conditions --- p.41 / Chapter 3.14 --- "Degradation of 1,000 mg/L of procion red MX-5B under optimized conditions" --- p.42 / Chapter 3.15 --- Temporal change of the concentration of procion red MX-5B in calcium alginate beads --- p.42 / Chapter 3.16 --- "Temporal change of the concentration of procion red MX-5B in alginate beads of 5,000 mg/L of Ti02" --- p.43 / Chapter 3.17 --- "Temporal change of the concentration of procion red MX-5B in alginate beads of 10,000 mg/L of Ti02" --- p.43 / Chapter 3.18 --- Effect of the concentration of titanium dioxide in alginate beads in the photocatalytic degradation of procion red MX-5B --- p.45 / Chapter 3.19 --- "Effect of hydrogen peroxide in the photocatalytic degradation of procion red MX-5B in 5,000 mg/L of Ti02-alginate beads" --- p.47 / Chapter 3.20 --- "Temporal change of the concentration of procion red MX-5B in alginate beads with 5,000 mg/L of Ti02" --- p.47 / Chapter 3.21 --- "Effect of biomass of Pseudomonas sp. K1 on the photocatalytic degradation of procion red MX-5B in alginate beads with 5,000 mg/L of Ti02" --- p.48 / Chapter 3.22 --- Diffuse reflectance-IR spectroscopic analysis of degradation product(s) --- p.49 / Chapter 3.23 --- Nuclear magnetic resonance (NMR) spectroscopic analysis of degradation products --- p.49 / Chapter 3.24 --- Toxicological evaluation of degradation products using Microtox® test --- p.51 / Chapter 4 --- Result --- p.54 / Chapter 4.1 --- Biosorption of dyes by Pseudomonas sp. K1 --- p.54 / Chapter 4.2 --- UV intensities of the eight Cole-Parmer UV lamps at 365 nm --- p.54 / Chapter 4.3 --- Determination of the peak absorbance of five azo dyes at different pH using scanning spectrophotometer --- p.54 / Chapter 4.4 --- Determination of dye concentration by measuring at peak absorbance --- p.66 / Chapter 4.5 --- Effect of initial concentration of procion red MX-5Bin photocatalytic degradation rate --- p.66 / Chapter 4.6 --- Effect of initial concentration of hydrogen peroxide on the photocatalytic degradation of procion red MX-5B --- p.73 / Chapter 4.7 --- Effect of initial pH on photocatalytic degradation of procion red MX-5B --- p.73 / Chapter 4.8 --- Effect of initial temperature on photocatalytic degradation of procion red MX-5B --- p.73 / Chapter 4.9 --- Effect of titanium dioxide on photocatalytic degradation of procion red MX-5B --- p.77 / Chapter 4.10 --- Effect of UV intensity on photocatalytic degradation of procion red MX-5B --- p.77 / Chapter 4.11 --- Photocatalytic degradation kinetics of different azo dyes --- p.77 / Chapter 4.12 --- Photocatalytic degradation of 40 mg/L of reactive red241 under optimized conditions --- p.77 / Chapter 4.13 --- Photocatalytic degradation of 40 mg/L procion red MX-5B under optimized conditions --- p.81 / Chapter 4.14 --- "Photocatalytic degradation of 1,000 mg/L of procion red MX-5B under optimized conditions" --- p.81 / Chapter 4.15 --- Temporal change of the concentration of procion red MX-5B in calcium alginate beads --- p.81 / Chapter 4.16 --- "Temporal changes of the concentration of procion red MX-5B in 5,000 mg/L of Ti02-alginate beads" --- p.85 / Chapter 4.17 --- "Temporal change of the concentration of procion red MX-5B in 10,000 mg/L of Ti02-alginate beads" --- p.85 / Chapter 4.18 --- Effect of the concentration of titanium dioxide in alginate beads in the photocatalytic degradation of procion red MX-5B --- p.89 / Chapter 4.19 --- "Effect of hydrogen peroxide in the photocatalytic degradation of procion red MX-5B in 5,000 mg/L of Ti02-alginate beads" --- p.89 / Chapter 4.20 --- "Temporal change of the concentration of procion red MX-5Bin alginate beads with 5,000 mg/L of Ti02" --- p.89 / Chapter 4.21 --- "Effect ofbiomass of Pseudomonas sp. K1 on the photocatalytic degradation of procion red MX-5B in 5,000 mg/L of Ti02-alginate beads" --- p.93 / Chapter 4.22 --- Degradation products analysis using diffuse reflectance-IR spectroscopy --- p.93 / Chapter 4.23 --- Degradation products analysis using nuclear magnetic resonance (NMR) --- p.101 / Chapter 4.24 --- Toxicological evaluation of degradation products using Microtox® test --- p.101 / Chapter 5 --- Discussion --- p.104 / Chapter 5.1 --- Biosorption of azo dyes in Pseudomonas sp. K-l --- p.104 / Chapter 5.2 --- Optimization of photocatalytic degradation of azo dyes --- p.105 / Chapter 5.2.1 --- Effect of initial concentration of procion red MX-5B on the photocatalytic degradation --- p.105 / Chapter 5.2.2 --- Effect of initial concentration of hydrogen peroxide on the photocatalytic degradation --- p.106 / Chapter 5.2.3 --- Effect of initial pH on the photocatalytic degradation --- p.107 / Chapter 5.2.4 --- Effect of initial temperature on the photocatalytic degradation --- p.108 / Chapter 5.2.5 --- Effect of titanium dioxide on the photocatalytic degradation --- p.109 / Chapter 5.2.6 --- Effect of UV intensity on the photocatalytic degradation --- p.110 / Chapter 5.2.7 --- Degradation kinetics of different dyes --- p.111 / Chapter 5.2.8 --- Optimized conditions for PCO of reactive red 241 and procion red --- p.112 / Chapter 5.3 --- Immobilization of titanium dioxide and Pseudomonas sp. K-l in alginate beads --- p.113 / Chapter 5.3.1 --- Temporal changes of the concentration of dye in alginate beads --- p.113 / Chapter 5.3.2 --- Effect of titanium dioxide in alginate beads in PCO --- p.114 / Chapter 5.3.3 --- Effect of hydrogen peroxide in alginate beads in PCO --- p.115 / Chapter 5.3.4 --- "Temporal change of dye concentration in alginate beads of 5,000 mg/L" --- p.115 / Chapter 5.3.5 --- Effect of biomass of Pseudomonas sp. K-l in alginate beads on the PCO of dye --- p.115 / Chapter 5.4 --- Diffuse reflectance IR spectroscopic analysis of degradation products --- p.116 / Chapter 5.5 --- 1HNMR analysis of degradation products --- p.119 / Chapter 5.6 --- Toxicological evaluation of degradation products using Microtox® test --- p.120 / Chapter 5.7 --- Application --- p.121 / Chapter 6 --- Conclusion --- p.122 / Chapter 7 --- References --- p.124 / Appendix 1 --- p.142 / Appendix 2 --- p.143
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Continuous color removal from concentrated dye waste discharges using reducing and oxidizing chemicals: a pilot plant studyPrice, Vaneaton 04 August 2009 (has links)
The purpose of this research was to design, fabricate and test a 1 liter per minute pilot plant with a cascading sequence of continuously stirred tank reactors. The object of the research was to chemically decolorize selected reactive-dye bath concentrates resulting from exhaustive dyeing, and to remove metals and DOC using Fenton's Reagent or the reductive chemicals, thiourea dioxide and sodium hydrosulfite. For the Fenton's Reagent studies, ferrous sulfate was premixed with the dye waste concentrate before overflowing to the first reactor.
A feedback control system based on color remaining in the discharge was used to regulate reactants added. Transmittance was measured at several wavelengths (590, 540, and 438 nm) and the American Dye Manufacturers Institute (ADMI) value calculated. The results demonstrated that ADMI measurements could not be made on dark solutions (over 3000 ADMI) in the pilot plant and, typically, one wavelength was used for control. DOC removal was used as a means of determining the biological activity in aerated reactors following color removal.
The initial pilot plant studies were conducted using Navy 106 jet-dye waste. Reductive pretreatment with thiourea dioxide resulted in 92.2% color removal with color returning upon aeration for an overall color removal of 76.6%. Oxidative pretreatment with Fenton's chemistry resulted in 98.8% color removal with overall color removal after aerobic treatment at 96.8%. Dissolved Organic Carbon (DOC) removal in aerobic treatment improved with oxidative pretreatment relative to reductive pretreatment on Navy 106 jet-dye concentrate.
On site operation of the pilot plant on other dye wastes showed color removals above 95% and DOC removals of 38% and 19% for an azo-based red dye waste concentrate and a copper-phthalocyanine-based dye, Ming Jade, respectively. The soluble copper concentration in the Ming Jade was decreased from 19.2 ppm to 4.5 ppm. This corresponded to a 3-fold increase in suspended solids from 0.575 g/L to 1.505 g/L.
The results showed that continuous oxidative pretreatment with a 15-minute residence time was controllable and more effective than reductive treatment for color removal. Oxidative pretreatment also decreased the soluble copper concentration in a copper containing waste water, and did not hinder biological activity. / Master of Science
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Aproveitamento tecnológico da casca de amendoim em processo de biossorção de corante têxtil / Technological use of peanut hulls in the process of textile dye biosorptionDall Orsoletta, Gabriel 30 March 2017 (has links)
As indústrias têxteis possuem grande potencial poluidor pois geram grandes quantidades de efluentes contendo compostos recalcitrantes, incluindo corantes. Diversos processos tem sido empregados na descontaminação de efluentes industriais e estudos indicam a adsorção empregando resíduos agroindustriais como matrizes adsorventes como processos promissores na remoção de cor. Neste contexto, o presente trabalho teve como objetivo avaliar a casca de amendoim como adsorvente alternativo no processo de remoção de corante têxtil (Reactive Blue 203) em meio sintético e de efluente industrial. Para isso, foram realizadas análises de caracterização do material adsorvente, revelando elevadas quantidade de fibras (69,25%), dentre elas os polissacarídeos (glucana e xilana) e de lignina (39,4%). A biomassa apresentou um pHpcz de 6,9, a microscopia eletrônica de varredura demonstrou que sua superfície é altamente porosa e a análise da superfície especifica por BET, indicou uma área superficial de 0,4431 m2.g-1 e diâmetro médio de poro de 20,120 Å na biomassa moída com tamanho de partícula de 0,250 mm. Um Delineamento Composto Central Rotacional 23 foi empregado para avaliar e definir as melhores condições de processo, sendo estudadas a influência dos parâmetros pH, temperatura da solução e granulometria do adsorvente sobre a capacidade de remoção de cor de efluente sintético (Reactive Blue 203). As variáveis pH e temperatura apresentaram influência significativa no processo de remoção de cor e como melhores condições de processo foram definidos pH de 3,0, temperatura de 30o C e granulometria de 0,250 mm. O tempo de equilíbrio foi alcançado após 400 minutos de contato. O modelo cinético de pseudo-segunda ordem foi o que melhor descreveu o processo de adsorção. As isotermas de adsorção foram avaliadas a partir dos modelos matemáticos de Langmuir e Freundlich, sendo que o modelo de Langmuir foi o que melhor descreveu o processo. Os parâmetros termodinâmicos indicam que a energia livre de Gibbs apresenta valores positivos indicando que o processo não é espontâneo. Valores negativos da entalpia sugerem uma natureza exotérmica da adsorção e valores negativos da entropia indicaram um aumento no grau de organização do sistema. A energia de ativação do processo de adsorção do corante sobre matriz a estudada, indicam uma adsorção química ativada. A casca de amendoim demonstrou ter potencial de remoção de cor em efluente industrial (66,83%), o que pode ser melhorado empregando condições de processos mais específicas. Por outro lado, a reutilização do material não foi ótima nas condições de dessorção empregas devendo ser melhor avaliado devido à natureza química da adsorção. / The textile industries have great potential for pollutants because they generate large quantities of effluents containing recalcitrant compounds, including dyes. Different processes have been employed in the decontamination of industrial effluents and studies indicate the adsorption using agroindustrial residues as adsorbent matrices as promising processes in the removal of color. In this context, the present work had the objective of evaluating peanut shell biomass as an alternative adsorbent in the process of dye removal (Reactive Blue 203) in synthetic and industrial effluent. For this, characterization analyzes of the adsorbent material were performed, revealing a high amount of fibers (69,25%), among them polysaccharides (glucan and xylan) and lignin (39,4%). The biomass showed a pHzcp of 6,9, the scanning electron microscopy demonstrated that its surface is highly porous and the BET specific surface analysis indicated a surface area of 0,4431 mg.g-1 and mean pore diameter of 20,120 Å in ground biomass with a particle size of 0,250 mm. A 23 central composite rotational design was use to evaluate and define the best process conditions, studing the influence of the parameters pH, solution temperature and adsorbent granulometry on the color removal capacity of synthetic effluent (Reactive Blue 203). The pH and temperature variables showed a significant influence on the color removal process and, as the best process conditions, pH of 3,0, temperature of 30oC and particle size of 0,250 mm were define. The equilibration time was reach after 400 minutes of contact. The kinetic model of pseudo-second order was the one which best described the adsorption process. The adsorption isotherms were evaluate from the mathematical models of Langmuir and Freundlich, and the Langmuir model best described the process. The thermodynamic parameters shown that Gibbs free energy presents positive values, indicating that the process is not spontaneous. Negative enthalpy values suggest an exothermic nature of the adsorption and negative entropy values indicate an increase in the degree of organization of the system. The activation energy of the dye adsorption process on the studied matrix indicates an activated chemical adsorption. The peanut hulls showed potential for color removal in industrial effluent (66,83%), which can be improved by employing more specific process conditions. On the other hand, the reutilization of the material was not optimal under the desorption conditions because the chemical nature of adsorption.
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Avaliação da capacidade de remoção de corante têxtil pelo fungo Lasiodiplodia theobromae MMPI em efluente sintético e industrialPizato, Everton 09 September 2013 (has links)
Os processos industriais de produção têxtil têm como característica o uso de grandes volumes de água durante as etapas de lavagem e tingimento de tecido, resultando em efluentes com enorme diversidade e complexidade química. A presença de corantes dissolvidos no efluente é bastante visível e problemática, considerando sua recalcitrância e cinética de degradação lenta. Neste trabalho, o fungo ascomiceto L. theobromae MMPI foi avaliado quanto à capacidade de remoção de cor do efluente sintético contendo corante azul reativo e de efluente industrial. Os ensaios com efluente sintético foram realizados em incubadora orbital shaker e em biorreator com cuba de 5 L. O meio foi suplementado com MgSO4.7H2O 2 g L-1, K2HPO4 2 g L-1, autoclavado (121o C/15 min), e acrescido de sacarose, nitrato de amônio e velocidade de agitação de acordo com delineamento composto central rotacional (DCCR), temperatura 28o C, inóculo padronizado e tempo para retirada das amostras de 72 h. A eficiência de remoção de cor variou de 31,58% até 91,60% e a produção de biomassa de 0,40 g L-1 a 8,70 g L-1. Foi observada ainda, a produção de um exopolissacarídeo (EPS) na ordem de 0,66 g L-1 a 9,70 g L-1. Na análise das estimativas dos efeitos (p<0,05) apenas o efeito linear da concentração de sacarose (p<0,000) e o efeito quadrático da concentração de nitrato de amônio (p<0,018) se mostraram significativos. O modelo obtido foi avaliado através da ANOVA, apresentando coeficiente de regressão elevado considerando um sistema biológico (R2 0,8483). Este modelo foi validado através de experimento a posteriori, indicando excelente correlação entre o valor preditivo (74,8%) e o valor observado (73,8%). Os ensaios em biorreator ratificaram o comportamento observado em incubadora shaker, obtendo-se 86% de descoloração do efluente sintético ao final de 72 horas de tratamento e 91,3% de descoloração ao final de 168 horas de tratamento para o efluente industrial. Após 168 h de incubação observou-se atividade enzimática de lacase (0,0563 U / ml). Os ensaios de toxicidade aguda com Artemia salina indicaram que a CL50 foi de aproximadamente 14,72% (v / v) para o efluente bruto, enquanto que o efluente submetido ao tratamento de oito dias o valor aproximado foi de 4,98% (v / v). Diversos autores relacionam os processos de descoloração a atividade enzimática, no entanto os resultados obtidos sugerem que a remoção de cor está relacionada a adsorção do corante na biomassa produzida. Estudos posteriores devem ser realizados para o melhor entendimento e confirmação de que a remoção de cor não está associada a biossíntese de enzimas degradadoras de estruturas fenólicas como as lacases. / The industrial processes of textile production are characterized by the use of large volumes of water during the steps of washing and dyeing fabric, resulting in effluent with enormous diversity and chemical complexity. The presence of dye dissolved in the effluent is quite noticeable and problematic, considering its recalcitrance and slow degradation kinetics. In this work, the fungus ascomiceto L. theobromae MMPI were evaluated for the ability to color removal from synthetic effluent containing blue dye reactive and industrial effluent. The tests with synthetic effluent were performed in incubator orbital shaker and in bioreactor with tub of 5L. The media was supplemented with MgSO4.7H2O 2 g L-1, K2HPO4 2 g L-1, autoclaved (121 C/15 min), plus sucrose, ammonium nitrate and stirring speed according to central composite design (CCDR), temperature 28 C, inoculum standardized and time to withdrawal of samples 72h. The color removal efficiency ranged from 31.58% to 91.60% and the biomass yield 0.40 g L-1 to 8.70 g L-1. It was still observed the production of an exopolysaccharide (EPS) in the range of 0.66 g L-1 to 9.70 g L-1. In the analysis of estimated effects (p <0.05) only the linear effect of sucrose concentration (p <0.000) and quadratic effect of the concentration of ammonium nitrate (p <0.018) were significant. The model was evaluated by ANOVA, with high regression coefficient considering a biological system (R2 0.8483). This model was validated by experiment retrospectively, indicating excellent correlation between the predictive value (74.8%) and the observed value (73.8%). The tests in bioreactor ratified the behavior observed in an incubator shaker to give 86% decolorization of synthetic effluent at the end of 72 hours of treatment of discoloration and 91.3% at the end of 168 hours of treatment for industrial effluent. After 168 h of incubation was observed laccase enzyme activity (0.0563 U / ml). The acute toxicity tests with brine shrimp showed that the LC50 was approximately 14.72% (v / v) for the raw wastewater, while the effluent subjected to the treatment eight days was approximately 4.98% (v / v). Several authors relate the processes of bleaching enzyme activity, however the results suggest that the color removal is related to the adsorption of the dye in the biomass produced. Further studies should be performed for better understanding and confirmation that the color removal is not associated with the biosynthesis of phenolic structures degrading enzymes such as laccases.
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Derivatizações aniônica e catiônica de resíduos do processamento dos fios de algodão para remoção de corantes têxteisBaldo, Gizele Rejane 17 February 2014 (has links)
CAPES / A indústria têxtil brasileira ocupa um importante papel na economia e se posiciona entre as 10 maiores produtoras mundiais. Seus efluentes, gerados no processo de tingimento dos tecidos, contém cargas de 15 a 50% de corantes, além de outros contaminantes. Com vistas à remediação ambiental destes efluentes, o resíduo do processamento dos fios de algodão (RA), que é coletado na própria unidade fabril, revelou-se um material atraente para a remoção de corantes após sua derivatização química com ácido monocloroacético (AMCA) ou cloreto dietilaminoetil.cloridrato (DEAE+reagente), obtendo matrizes iônicas do tipo carboximetil-RA (CM--RA) e dietilaminoetil-RA (DEAE+-RA), respectivamente. Estas matrizes foram obtidas através de delineamentos experimentais, sendo que para a CM--RA foram avaliados
os fatores: a) concentração de NaOH; b) volume de isopropanol e c) quantidade de AMCA, enquanto que para a DEAE+-RA, os fatores foram: a) concentração de NaOH e b) quantidade de DEAE-reagente. Tais matrizes foram ensaiadas, respectivamente, quanto à eficiência na retenção de corantes: catiônico, C.I. Basic Blue 41 (BB 41) e aniônico, C.I. Reactive Red 239 (RR 239), em experimentos em coluna e batelada. Também foi avaliada a biodegradabilidade desses materiais utilizando enzimas celulolíticas. Para as melhores matrizes obtidas foram realizados experimentos adicionais quanto à eficiência de retenção dos corantes (concentração inicial, tempo de contato e adição de sais), a biodegradabilidade após a retenção dos corantes e o ensaio de regeneração das matrizes. Para a CM--RA, a eficiência de captação de corante catiônico foi predominantemente determinada pela concentração de álcali. A inclusão do maior volume de isopropanol resultou em incremento da eficiência, entretanto, com custo adicional não justificável. A melhor matriz obtida na ausência de isopropanol apresentou valores de retenção para os
testes em coluna e batelada maior que um produto comercial do tipo carboximetilcelulose. Para o teste de biodegradabilidade, as amostras derivatizadas tiveram hidrólises próximas aos controles com adição de NaOH. Para o DEAE+-RA, a principal variável responsável pela eficiência da retenção de corantes foi a quantidade do derivatizante, sendo que nos ensaios em coluna e batelada a resposta foi semelhante ao obtido com um produto comercial DEAE-Celulose. Através do teste de biodegradabilidade observou-se que a derivatização reduziu a porcentagem de hidrólise quando comparada aos seus controles com NaOH. Para as melhores matrizes, o ensaio de concentração inicial de corantes indicou que a retenção é maior com o aumento da concentração. Quanto à adição de NaCl, houve redução da retenção de corante na matriz carboximetilada enquanto para a dietilaminoetilada a influência foi positiva acima de 50 mM. A presença de corante reduziu em 4,10 e 37,36 % a hidrólise das matrizes carboximetilada e
dietilaminoetilada, respectivamente. No presente trabalho, os derivados CM--RA e DEAE+-RA se revelaram eficientes para a remoção dos corantes BB 41 e RR 239, respectivamente, podendo assim se apresentar como uma alternativa no tratamento de efluentes têxteis. / The Brazilian textile industry occupies an important role in the economy and ranks among the 10 largest world producers The effluents generated in the process of fabrics dyeing contain 15 to 50% of dyes and others contaminants. With a view to environmental remediation of these effluents, the processing of cotton yarn waste (cotton dust waste - CDW) that is collected in the plant itself, proved to be an attractive material for the removal of the residual dyes effluents after the chemical derivatization with monochloroacetic acid (MCAA) or diethylaminoethyl chloride.hydrochloride (DEAE+reagent), thus originating matrices carboxymethyl- CDW (CM--CDW) and diethylaminoethyl-CDW (DEAE+-CDW), respectively. These matrices were obtained using experimental designs, when for CM--CDW three factors were evaluated: a) concentration of NaOH; b) volume of isopropanol and c) amount of MCAA, while for DEAE+-CDW, the factors were: a) concentration of NaOH and b) amount of DEAE+reagent. These matrices were tested for their effectiveness in the retention of dyes: the cationic, C. I. Basic Blue 41 (BB 41) and the anionic, C. I.
Reactive Red 239 (RR 239), both in column and batch experiments. Also, the biodegradability of these materials was tested. For the best matrices obtained,
additional experiments regarding the retention efficiency of the dyes (initial concentration, contact time and addition of salts) and matrices biodegradability after the dye retention were also carried out. For the CM--CDW, the efficiency of uptake of the cationic dye was predominantly determined by the concentration of alkali. The inclusion of the higher volume of isopropanol in the pretreatment step resulted in improved efficiency, but with an additional cost not justifiable. The best matrix obtained in the absence of isopropanol showed retention values for column and batch experiments with respective efficiencies of 3.9 and 2 times higher than a commercial CM-cellulose. For the biodegradability test, the samples of experimental design showed close enzymatic hydrolysis compared with the controls with alkali. For the DEAE+-CDW, the main variable for the efficiency of dye retention is predominantly determined by the amount of DEAE+reagent. The maximum retention of the anionic dye was obtained in columns while the batch alternatve performance was close to that of a commercial DEAE-Cellulose. The biodegradability test revealed that the derivatization with DEAE+reagent reduced the percentage of hydrolysis by cellulases when compared to the controls with NaOH. The initial concentration test of dye indicated that the retention increases with increased dye concentration and contact time to reach equilibrium which was higher in the higher concentrations in both matrices. The addition of NaCl decreased the dye retention for the carboxymethylated matrix and for the diethylaminoethylizated matrix the influence was positive only after addition of 50 mM. The presence of dye in the matrices derivatized reduced the hydrolysis in 4.10 and 37.36 % for carboxymethylated and diethylaminoethylizated matrices, respectively. Therefore, the CM--CDW and DEAE+- CDW derivatives of CDW proved effective for the removal of the dyes BB 41 and RR 239, respectively, and thus both represent important alternatives in the treatment of colored textile effluents.
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Derivatizações aniônica e catiônica de resíduos do processamento dos fios de algodão para remoção de corantes têxteisBaldo, Gizele Rejane 17 February 2014 (has links)
CAPES / A indústria têxtil brasileira ocupa um importante papel na economia e se posiciona entre as 10 maiores produtoras mundiais. Seus efluentes, gerados no processo de tingimento dos tecidos, contém cargas de 15 a 50% de corantes, além de outros contaminantes. Com vistas à remediação ambiental destes efluentes, o resíduo do processamento dos fios de algodão (RA), que é coletado na própria unidade fabril, revelou-se um material atraente para a remoção de corantes após sua derivatização química com ácido monocloroacético (AMCA) ou cloreto dietilaminoetil.cloridrato (DEAE+reagente), obtendo matrizes iônicas do tipo carboximetil-RA (CM--RA) e dietilaminoetil-RA (DEAE+-RA), respectivamente. Estas matrizes foram obtidas através de delineamentos experimentais, sendo que para a CM--RA foram avaliados
os fatores: a) concentração de NaOH; b) volume de isopropanol e c) quantidade de AMCA, enquanto que para a DEAE+-RA, os fatores foram: a) concentração de NaOH e b) quantidade de DEAE-reagente. Tais matrizes foram ensaiadas, respectivamente, quanto à eficiência na retenção de corantes: catiônico, C.I. Basic Blue 41 (BB 41) e aniônico, C.I. Reactive Red 239 (RR 239), em experimentos em coluna e batelada. Também foi avaliada a biodegradabilidade desses materiais utilizando enzimas celulolíticas. Para as melhores matrizes obtidas foram realizados experimentos adicionais quanto à eficiência de retenção dos corantes (concentração inicial, tempo de contato e adição de sais), a biodegradabilidade após a retenção dos corantes e o ensaio de regeneração das matrizes. Para a CM--RA, a eficiência de captação de corante catiônico foi predominantemente determinada pela concentração de álcali. A inclusão do maior volume de isopropanol resultou em incremento da eficiência, entretanto, com custo adicional não justificável. A melhor matriz obtida na ausência de isopropanol apresentou valores de retenção para os
testes em coluna e batelada maior que um produto comercial do tipo carboximetilcelulose. Para o teste de biodegradabilidade, as amostras derivatizadas tiveram hidrólises próximas aos controles com adição de NaOH. Para o DEAE+-RA, a principal variável responsável pela eficiência da retenção de corantes foi a quantidade do derivatizante, sendo que nos ensaios em coluna e batelada a resposta foi semelhante ao obtido com um produto comercial DEAE-Celulose. Através do teste de biodegradabilidade observou-se que a derivatização reduziu a porcentagem de hidrólise quando comparada aos seus controles com NaOH. Para as melhores matrizes, o ensaio de concentração inicial de corantes indicou que a retenção é maior com o aumento da concentração. Quanto à adição de NaCl, houve redução da retenção de corante na matriz carboximetilada enquanto para a dietilaminoetilada a influência foi positiva acima de 50 mM. A presença de corante reduziu em 4,10 e 37,36 % a hidrólise das matrizes carboximetilada e
dietilaminoetilada, respectivamente. No presente trabalho, os derivados CM--RA e DEAE+-RA se revelaram eficientes para a remoção dos corantes BB 41 e RR 239, respectivamente, podendo assim se apresentar como uma alternativa no tratamento de efluentes têxteis. / The Brazilian textile industry occupies an important role in the economy and ranks among the 10 largest world producers The effluents generated in the process of fabrics dyeing contain 15 to 50% of dyes and others contaminants. With a view to environmental remediation of these effluents, the processing of cotton yarn waste (cotton dust waste - CDW) that is collected in the plant itself, proved to be an attractive material for the removal of the residual dyes effluents after the chemical derivatization with monochloroacetic acid (MCAA) or diethylaminoethyl chloride.hydrochloride (DEAE+reagent), thus originating matrices carboxymethyl- CDW (CM--CDW) and diethylaminoethyl-CDW (DEAE+-CDW), respectively. These matrices were obtained using experimental designs, when for CM--CDW three factors were evaluated: a) concentration of NaOH; b) volume of isopropanol and c) amount of MCAA, while for DEAE+-CDW, the factors were: a) concentration of NaOH and b) amount of DEAE+reagent. These matrices were tested for their effectiveness in the retention of dyes: the cationic, C. I. Basic Blue 41 (BB 41) and the anionic, C. I.
Reactive Red 239 (RR 239), both in column and batch experiments. Also, the biodegradability of these materials was tested. For the best matrices obtained,
additional experiments regarding the retention efficiency of the dyes (initial concentration, contact time and addition of salts) and matrices biodegradability after the dye retention were also carried out. For the CM--CDW, the efficiency of uptake of the cationic dye was predominantly determined by the concentration of alkali. The inclusion of the higher volume of isopropanol in the pretreatment step resulted in improved efficiency, but with an additional cost not justifiable. The best matrix obtained in the absence of isopropanol showed retention values for column and batch experiments with respective efficiencies of 3.9 and 2 times higher than a commercial CM-cellulose. For the biodegradability test, the samples of experimental design showed close enzymatic hydrolysis compared with the controls with alkali. For the DEAE+-CDW, the main variable for the efficiency of dye retention is predominantly determined by the amount of DEAE+reagent. The maximum retention of the anionic dye was obtained in columns while the batch alternatve performance was close to that of a commercial DEAE-Cellulose. The biodegradability test revealed that the derivatization with DEAE+reagent reduced the percentage of hydrolysis by cellulases when compared to the controls with NaOH. The initial concentration test of dye indicated that the retention increases with increased dye concentration and contact time to reach equilibrium which was higher in the higher concentrations in both matrices. The addition of NaCl decreased the dye retention for the carboxymethylated matrix and for the diethylaminoethylizated matrix the influence was positive only after addition of 50 mM. The presence of dye in the matrices derivatized reduced the hydrolysis in 4.10 and 37.36 % for carboxymethylated and diethylaminoethylizated matrices, respectively. Therefore, the CM--CDW and DEAE+- CDW derivatives of CDW proved effective for the removal of the dyes BB 41 and RR 239, respectively, and thus both represent important alternatives in the treatment of colored textile effluents.
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Descoloração e degradação do azo corante vermelho BR por ozonizaçãoTrevizani, Jéssica Luiza Bueno 24 April 2015 (has links)
CAPES / A indústria têxtil é responsável pela geração de efluentes com elevada carga orgânica, cor e toxicidade. O principal objetivo deste trabalho foi avaliar a eficiência de remoção de um corante azo-reativo (Vermelho BR) pelo processo de ozonização em variações de pH e concentração inicial do corante para duas soluções: solução aquosa acrescida de corante (Solução 1) e solução de efluente sintético acrescido de corante (Solução 2). Para tal, os ensaios foram realizados em pH 4 (ácido), pH 7 (neutro) e pH 10 (alcalino) e a concentração inicial do corante foi variada em 50, 100 e 150 mg/L. As coletas foram realizadas de 15 em 15 minutos e os parâmetros analisados para Solução 1 foram: temperatura, remoção de cor, turbidez, ozônio dissolvido, off-gas e ozônio consumido; para Solução 2, além desses parâmetros também foi analisada a remoção de matéria orgânica (DQO). O tempo de ozonização ocorreu até a remoção significativa da cor (>90%) e variou entre 60 e 240 min. A produção de ozônio utilizada neste trabalho foi a máxima obtida pelo gerador de 0,702 gO3/h em vazão máxima de ar (15 L/min). A eficiência máxima de transferência de ozônio para o líquido foi de 73% em meio alcalino (pH igual a 10) e mínimas em condições ácidas (pH igual a 4) para ambas as soluções analisadas. Através da aplicação do delineamento de composto central (DCC) e dos gráficos de superfície de resposta, pode-se verificar a influência dos fatores concentração inicial de corante (Fator 1) e pH (Fator 2) na variável resposta remoção de corante. Dessa forma pode-se observar que a influência da concentração inicial do corante é mais significativa do que a influência do pH na eficiência de remoção do corante. A eficiência máxima de remoção foi de 98% para Solução 1 e para Solução 2 em pH 10 e 4 respectivamente e com concentração inicial de corante de 50 mg/L. A fim de analisar a toxicidade das soluções, antes e após a ozonização, foram realizados testes de toxicidade aguda com o organismo teste Daphinia similis e verificou-se toxicidade em todas as amostras analisadas. Ao longo deste trabalho pode-se observar que a ozonização tem resultados eficientes na oxidação do corante têxtil Vermelho BR em todas as variações de pH e concentração de corante. / The textile industry is responsible for generating wastewater with high organic content, color and toxicity. The direct objective of this study was to evaluate the hum dye removal efficiency azo-Reactive (Red BR) by ozonation process in pH variations and initial dye concentration. For two solutions: dye plus aqueous solution (Solution 1) and synthetic effluent solution plus dye (Solution 2). To this end, tests were performed at pH 4 (acid), pH 7 (neutral) and pH 10 (alkaline) and the initial dye concentration varied among 50, 100 and 150mg / L As samples were performed from 15 to 15 minutes and the parameters were analyzed. for Solution 1 were: temperature, color removal, turbidity, dissolved ozone, off-gas and ozone consumed. For solution 2, besides these parameters, was also analyzed the removal of organic matter (COD). The rate of ozonation has occurred up to a significant removal of color (> 90%) and between 60 and 240 min.The Ozone production used in this work was a Maximum obtained with Generator 0702 GO3 / h in air flow Maximum (15 L / min). The Maximu m Efficiency of transfer Ozone to the net was 73% in alkaline medium (pH 10) and minimum under acidic conditions (pH 4) For both analyzed solutions. through the application of the central compound design (DCC) and Polling Surface Graphics, it is possible to check the initial dye concentration factors of influence (Factor 1) and pH (Factor 2) in the Variable Voting dye removal. This can be observed as forms of Influence of the initial dye concentration and more significant is that the influence of pH dye removal efficiency. Maximum efficiency removal was 98% For Solution 1 and 2 sat pH 10:04 and initial concentration of dye 50 mg / L. In order to analyze the toxicity of solutions, the before and after process of ozonation, tests were performed as toxicity test with the body similis daphinia and found toxicity at all samples. During this work, it was observed that the ozonation has results in efficient oxidation of dye textile Red BR in all pH variations and dye concentration.
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Descoloração e degradação do azo corante vermelho BR por ozonizaçãoTrevizani, Jéssica Luiza Bueno 24 April 2015 (has links)
CAPES / A indústria têxtil é responsável pela geração de efluentes com elevada carga orgânica, cor e toxicidade. O principal objetivo deste trabalho foi avaliar a eficiência de remoção de um corante azo-reativo (Vermelho BR) pelo processo de ozonização em variações de pH e concentração inicial do corante para duas soluções: solução aquosa acrescida de corante (Solução 1) e solução de efluente sintético acrescido de corante (Solução 2). Para tal, os ensaios foram realizados em pH 4 (ácido), pH 7 (neutro) e pH 10 (alcalino) e a concentração inicial do corante foi variada em 50, 100 e 150 mg/L. As coletas foram realizadas de 15 em 15 minutos e os parâmetros analisados para Solução 1 foram: temperatura, remoção de cor, turbidez, ozônio dissolvido, off-gas e ozônio consumido; para Solução 2, além desses parâmetros também foi analisada a remoção de matéria orgânica (DQO). O tempo de ozonização ocorreu até a remoção significativa da cor (>90%) e variou entre 60 e 240 min. A produção de ozônio utilizada neste trabalho foi a máxima obtida pelo gerador de 0,702 gO3/h em vazão máxima de ar (15 L/min). A eficiência máxima de transferência de ozônio para o líquido foi de 73% em meio alcalino (pH igual a 10) e mínimas em condições ácidas (pH igual a 4) para ambas as soluções analisadas. Através da aplicação do delineamento de composto central (DCC) e dos gráficos de superfície de resposta, pode-se verificar a influência dos fatores concentração inicial de corante (Fator 1) e pH (Fator 2) na variável resposta remoção de corante. Dessa forma pode-se observar que a influência da concentração inicial do corante é mais significativa do que a influência do pH na eficiência de remoção do corante. A eficiência máxima de remoção foi de 98% para Solução 1 e para Solução 2 em pH 10 e 4 respectivamente e com concentração inicial de corante de 50 mg/L. A fim de analisar a toxicidade das soluções, antes e após a ozonização, foram realizados testes de toxicidade aguda com o organismo teste Daphinia similis e verificou-se toxicidade em todas as amostras analisadas. Ao longo deste trabalho pode-se observar que a ozonização tem resultados eficientes na oxidação do corante têxtil Vermelho BR em todas as variações de pH e concentração de corante. / The textile industry is responsible for generating wastewater with high organic content, color and toxicity. The direct objective of this study was to evaluate the hum dye removal efficiency azo-Reactive (Red BR) by ozonation process in pH variations and initial dye concentration. For two solutions: dye plus aqueous solution (Solution 1) and synthetic effluent solution plus dye (Solution 2). To this end, tests were performed at pH 4 (acid), pH 7 (neutral) and pH 10 (alkaline) and the initial dye concentration varied among 50, 100 and 150mg / L As samples were performed from 15 to 15 minutes and the parameters were analyzed. for Solution 1 were: temperature, color removal, turbidity, dissolved ozone, off-gas and ozone consumed. For solution 2, besides these parameters, was also analyzed the removal of organic matter (COD). The rate of ozonation has occurred up to a significant removal of color (> 90%) and between 60 and 240 min.The Ozone production used in this work was a Maximum obtained with Generator 0702 GO3 / h in air flow Maximum (15 L / min). The Maximu m Efficiency of transfer Ozone to the net was 73% in alkaline medium (pH 10) and minimum under acidic conditions (pH 4) For both analyzed solutions. through the application of the central compound design (DCC) and Polling Surface Graphics, it is possible to check the initial dye concentration factors of influence (Factor 1) and pH (Factor 2) in the Variable Voting dye removal. This can be observed as forms of Influence of the initial dye concentration and more significant is that the influence of pH dye removal efficiency. Maximum efficiency removal was 98% For Solution 1 and 2 sat pH 10:04 and initial concentration of dye 50 mg / L. In order to analyze the toxicity of solutions, the before and after process of ozonation, tests were performed as toxicity test with the body similis daphinia and found toxicity at all samples. During this work, it was observed that the ozonation has results in efficient oxidation of dye textile Red BR in all pH variations and dye concentration.
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Remoção de matéria orgânica e cor de efluente kraft por adsorção usando carvão ativado e argilaHinojosa, Eduardo Alberto Lazo 17 October 2014 (has links)
CAPES / Atualmente há preocupação da sociedade em relação aos impactos gerados pelas indústrias ao meio ambiente. Para produção de celulose e de papel é usada grande quantidade de água, madeira e produtos químicos, sendo gerado efluente nos diferentes processos produtivos da indústria. A matéria orgânica e a cor do efluente do processo Kraft se devem à presença de moléculas derivadas da lignina que são difíceis de serem removidas ou biodegradadas. Com vistas à remedição deste efluente, o presente trabalho busca avaliar a remoção de cor e matéria orgânica residual de efluente de celulose Kraft pré-tratado biologicamente, usando carvão ativado de casca de coco e argila montmorilonita pelo método de adsorção através de delineamentos experimentais. Para remoção de cor e matéria orgânica foram avaliados os fatores: a) pH do efluente; b) massa do material adsorvente no processo de adsorção e c) temperatura. A capacidade de adsorção de matéria orgânica e cor no carvão ativado e argila montmorilonita foram determinados pelo modelo matemático de Langmuir e Freundlich, por meio de ensaios de construção de isotermas de adsorção em efluente Kraft. O efluente foi caracterizado quanto a DQO, DBO5,20, COT e cor verdadeira antes e depois do tratamento terciário. Para o tratamento do efluente foram empregadas duas temperaturas: 25 e 40°C, seguiu-se planejamento fatorial completo 32 em triplicata com ponto central tendo como variáveis pH (5,0; 6,0 e 7,0) e massa de material adsorvente (0,5; 1,0 e 1,5 g). O planejamento experimental utilizado permitiu obter os melhores resultados com carvão ativado em 40 °C, pH 7,0 e 1,5 g de adsorvente com remoção de: 98% de COT, 83% de DQO, 97% de DBO5,20 e 95% de cor verdadeira e para argila em temperatura de 40 oC, pH 7, e 1,5 g de adsorvente com remoção de: 55% de COT, 50% de DQO, 90% de DBO5,20, e 56% de cor verdadeira. A principal variável responsável pela remoção de cor e matéria orgânica foi a massa de adsorvente seguida do pH. Também foi avaliada a possibilidade de aproveitamento do resíduo obtido a partir do processo de adsorção na incorporação de cinzas de carvão na produção de argamassas com teores de 0,4%, 1,0% e 1,2%; em cimento portland, areia e água com tempos de cura de 7 e 28 dias fazendo testes de resistência à compressão. Para a reutilização da argila foram utilizados 15% de argila do processo de adsorção, 25% de vidro e 60% de argila vermelha, para a confecção de corpos de prova cerâmico à temperatura de 1100 oC a 1150 oC. De modo geral, o processo de tratamento proposto neste trabalho utilizando carvão ativado, demostrou ser boa alternativa comparado com argila montmorilonita para redução de cor e matéria orgânica residual do efluente de processo Kraft, tendo-se em vista a utilização da cinza do carvão utilizado no processo de adsorção como um agregado para formação de argamassas na construção civil e argila utilizada na adsorção como material cerâmico. / Nowadays, there is a concern of society regarding the impacts caused by the industries on the environment. Large amounts of water, wood and chemichal are used to produce cellulose and paper, and contaminated effluents are generated through the various industrial processes associated. The organic matter and the color of the Kraft effluent are due to the presence of lignin-derived molecules that are difficult to be removed or biodegraded. With intent to remediate this effluent, this study aim to evaluate the removal of color and residual organic matter from biologically pretreated Kraft effluent, using activated carbon from coconut shell and montmorillonite clay by adsorption method through experimental designs. For the color and organic matter removal, the following factors were evaluated: a) pH of the effluent; b) the mass of the adsorbent material in the adsorption process and c) temperature. The adsorption capacity of organic matter and color in the activated carbon and in the montmorillonite clay were determined by the mathematical model of Langmuir and Freundlich, by means of isotherm adsorption construction in Kraft effluent.The effluent was characterized by COD, DBO5,20, COT and true color before and after the tertiary treatment. For it treatment two temperatures were employed: 25 °C and 40 °C, followed by a 32 full factorial design with center point in triplicate, using pH (5.0, 6.0 and 7.0) and masses of adsorbent material (0.5, 1.0 and 1.5 g) as variables. The experimental design used showed that the best results with activated carbon are obtained at 40 ° C, pH 7.0 and 1.5 g of adsorbent with removals of 98% of TOC, 83% of COD, 97% of BOD5,25 and 95% of true color. With clay, the best results occurred at temperature of 40 ° C, pH 7, and 1.5 g of adsorbent to remove 55% of COT, 50% of COD, 90% of BOD5,20 and 56% of true color. The main responsible for the removal of color and organic matter was the mass of adsorbent, followed by the pH. It was also evaluated the possibility of using the residue obtained from the adsorption process in the incorporation of carbon ash to produce mortars with levels of 0.4%, 1.0% and 1.2% in Portland cement, sand and water, with curing times of 7 and 28 days, for which compressive strength tests were performed. To reuse the clay, 15% of the clay from the adsorption process was used, together with 25% of glass and 60% of red clay, in order to construct ceramics bodies specimen generated at temperatures from 1100 °C to 1150 °C. The treatment process proposed in this work using activated carbon demonstrated to be, in general, a good alternative compared to montmorillonite clay for the color reduction and residual organic matter removal from Kraft process effluent, while residues from both process can be used as aggregates for mortars and ceramic body production.
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