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Textile industries are the major users of dyes in the world. A huge fraction of dyes are discharged out from the textile industries, causing serious damage to the environment. Bioremediation based technologies has been proved to be the most desirable and cost- effective method to counter textile dye pollution. The ability of the microorganisms to decolorize and metabolize dyes can be employed to treat the environment polluted by textile dyes. In this work, a total of 84 bacterial strains were isolated from Kelambakkam Solar Salt Crystallizer ponds (or salterns) and screened for their ability to produce extracellular tannase and laccase enzymes and eventually to decolorize three widely used textile dyes- Reactive Blue 81, Reactive Red 111 and Reactive Yellow 44. Of these 84 strains, 18 strains exhibited tannase activity and 36 strains showed positive laccase enzyme activity. The 11 bacterial strains that displayed both tannase and laccase enzyme activity were screened for their ability to decolorize the three textile azo dyes (100 mg/L). Out of 11 strains only 2 strains i.e., AMETH72 and AMETH77 showed best decolorization (%) in all the three dyes under static condition at room temperature. Repeated- batch immobilization study used to select the most efficient bacterial strain revealed that, isolate AMETH72 was efficient than AMETH77 in decolorizing the dyes. The 16S rRNA sequencing of AMETH72 showed 99% phylogenetic similarity to Halomonas elongata. The dye degradation products analyzed by FTIR and UV-Vis techniques displayed complete disruption of azo linkages and biodegradation of dyes to simpler compounds. The treated dyes also improved growth and total chlorophyll content in Wheat and Green gram seedlings, as compared to the untreated dyes. This indicated the non- toxicity of the biologically degraded dye products. Thus the entire study concluded that halotolerant marine bacteria from the salterns can be effectively used to bioremediate the textile dyes. / Program: MSc in Resource Recovery - Industrial Biotechnology

This research investigated the efficacy of chlorine dioxide (ClO₂), ultraviolet (UV) irradiation, UV in combination with chlorine dioxide (UV/ClO₂), and UV in combination with hydrogen peroxide (UV/H₂O₂) for decolorizing three reactive azo dyes (sultan red, indigo blue and cypress green) and treated textile-manufacturing wastewater. The objective was to determine the best treatment for reducing color to the Virginia Pollutant Discharge Elimination System (VPDES) permit level of 300 American Dye Manufacturers Institute (ADMI) units. The effects of the three chemical oxidation treatments provided color reduction for all three dyes. The results suggested UV/H₂O₂ and UV/ClO₂2 treatments provided maximum color reduction of the red and blue dyes, and UV/H₂O₂ was the most effective for maximum reduction of the green dye. A research goal was to provide predictive models of the wastewater effluent for the treatment processes, including the UV exposure time required to reach the 300 ADMI permit value and the effective ClO₂ dose necessary to achieve the 300 units. The results of the investigations regarding the effluent indicated that UV/H₂O₂ and UV/ClO₂ (5 mg/L) provided reduction to 300 units in less than 10 minutes UV exposure when the initial effluent color was less than 500 ADMI units. Without the addition of oxidant, contact times longer than 10 minutes were required for UV to decolorize these effluents to 300 ADMI units. Chlorine dioxide dosages between 10 and 30 mg/L both with and without UV irradiation achieved the same results. / Master of Science

<p>Reactive Black 5 and Procion Red MX 5B, an azo and anthraquinone dye repectively were decoulorized by mean of microorganisms growing on wood chips. The process consisted of three reactors, two anaerobic reactors and one aerobic reactor. The anaerobic process was used in order to make it possible to break the nitrogen bond of the azo group, (-N=N-) and the aerobic one to increase the possibility for the degradation of possible intermediates. After pumping wastewater through the system it was shown that mixtures or Reactive Black 5 and Procion Red MX 5B were efficiently decolourised at 50 mg/l as well as 200 mg/l of each of the dyes.</p><p><strong> </strong></p>

Pollution created by textile dyeing operations attracts significant attention because an effluent containing a complex mixture of coloured and potentially toxic compounds can be released with the discharged water. Developing dyes and dyeing conditions to reduce the amount of residual dye contained in any effluent has been one of many approaches to minimise this environmental impact. However, the presence of coloured discharge cannot be totally eliminated using only this strategy. Thus, development of efficient post-dyeing wastewater treatment methods capable of removing coloured products from the water is of paramount importance. TiO2-mediated photocatalytic degradation of organic dye molecules via oxidation is the focus of the study reported in this thesis. TiO₂ significantly increases the rate of photodegradation of a wide range of organic dyes under mild operating conditions, and is able to mineralise a wide spectrum of organic contaminants. TiO₂ is also one of the very few substances appropriate for the industrial applications. One of primary aims of this thesis is to test the hypothesis that augmenting standard TiO₂ photocatalysts with Au nanoparticles could increase performance of a catalyst, while immobilizing TiO₂ on SiO₂ support may improve the cost of the process efficiency, i.e. more photocatalytic degradation per particle of TiO₂. Combining TiO₂ doped with gold nanoparticles on SiO₂ support has the potential to provide the highest photocatalytic ability at the lowest cost. The first half of the thesis is concerned with establishing and optimizing experimental conditions for monitoring photodegradation via UV-Visible spectroscopy. Effects of various conditions such as temperature, sequence of addition of reagents, exposure to light vs. experiments in dark, sampling methods, and the use of quenching agent were examined. The main conclusions from this study are that light-induced photodegradation using titanium dioxide nanoparticles catalysts is comparatively more efficient than purely chemical catalytic (e.g. non-light mediated) degradation, even if the latter is performed at elevated temperature. Further, the rate of dye degradation is affected considerably by the parameters of the system. The degradation rate depends strongly on the pH of the solution, due to charges on both the catalyst surface and in the dye. In general, at pH ≤ 6.8, which is the zero charge point for TiO₂, reactions proceeded faster than those at higher pH. Six dyes from four different classes of dyes used in industry were used in this study, and all showed different photodegradation behaviour. The second half of thesis tests the photocatalytic abilities of various TiO₂-based catalysts: pure TiO₂ (commercial and custom-made in our laboratory), TiO₂-supported gold nanoparticles (Au/TiO₂), SiO₂-supported TiO₂ (TiO₂/SiO₂), and SiO₂-supported Au/TiO₂. The best photocatalytic performance was observed for the custom-made TiO₂ code-named as e-TiO₂, which was synthesized using the sol-gel method in dry ethanol. TiO₂-supported Au55 nanoparticles showed a similar level of catalytic ability but are significantly more expensive. It was observed that dye adsorption played a significant role in the case of SiO₂-immobilized photocatalysts.

Över 60% av de textilier som slängs i Sverige är fortfarande i användbart skick och genomsnittssvensken slänger cirka 8 kg textilier per år. Efterfrågan på textilier ökar trots det stora överflödet och det beräknas finnas ett underskott på ca 5 miljoner ton cellulosabaserade fibrer redan vid år 2020. För att leda konsumenter till att agera mer hållbart kan designers ta hjälp av olika designstrategier. Användandet av hållbara designstrategier kan förlänga ett plaggs livscykel och ett av dessa sätt kan vara att göra om befintliga plagg för att passa nuvarande behov hos konsumenten. Befintliga designverktyg saknar innehåll om omfärgning, trots att forskning visat att detta är en av förändringarna konsumenterna främst vill kunna göra på sina plagg. Syftet med denna studie är att utforma ett designverktyg som skapar rätt förutsättningar för omfärgning av bomullsplagg i konsumentfasen. Studien är avgränsad till att endast undersöka förutsättningarna för bomullsplagg och tar inte hänsyn till ekonomiska perspektiv.   Det här arbetet består av en litteraturstudie samt en empirisk studie. Litteraturstudien behandlar ämnena bomull, designverktyg samt färg och beredning av bomull. Det huvudsakliga empiriska materialet har samlats in via intervjuer med verksamma inom området färg och beredning samt en miljökemist. Säkerhetsdatablad från marknadens största textilfärgstillverkare har undersökts. Resultatet visar på flera faktorer som påverkar en omfärgning samt tar hänsyn till dessa i det skapade designverktyget. Faktorer som kan påverka resultatet är bland annat val av material och sytråd samt val av behandlingar och beredningar. Resultatet visade även att utfallet av den nya färgen är beroende av plaggets ursprungsfärg. / Over 60% of the textiles thrown away in Sweden are still usable and the average Swedish person throws away approximately 8 kg of textiles per year. The demand for textiles is increasing despite the abundance and it is calculated to be a deficit in cellulosic fibers in 2020 with 5 million tons. To lead consumers to act more sustainable, designers can use different design strategies. The use of sustainable design strategies can prolong the life cycle of a garment and one way to do it is by redesigning existing garments to fit the need of the consumer. Existing design tools are lacking content about redyeing, even though research has shown this is something the consumers would like to be able to change in their garments. The purpose of this thesis is to develop av design tool that creates the right conditions for redying cotton garments in the consumer phase. The study is delimited to only examine the conditions for cotton garments and does not take economic perspectives into account.   This study consists of a literature study and an empirical study. The literature study treats the subjects cotton, design tools, colour and finishing. The main empirical material is collected through interviews with people in the field of colour and finishing and with an environmental chemist. Safety data sheets from the biggest textile colour manufacturers on the market in Sweden has been studied. The results of the study show several factors that can affect the result of the redyeing process and takes these factors in consideration in the development of a design tool. Factors that can affect the result of a redyeing process are the choice of materials and sewing thread and choice of treatments and finishes on the fabric. The result also found that the outcome of the new colour is dependant on the original color of the garment.

Orientador: Carlos Renato Corso / Banca: Cassiana Maria Reganhan Coneglian / Banca: Sandra Mara Martins Franchetti / Resumo: Este trabalho apresenta uma avaliação comparativa do potencial biossortivo e biodegradativo da levedura Saccharomyces cerevisiae na remoção de corantes têxteis de efluentes quando imobilizada em alginato de cálcio e quando em célula livre. Para isto foram preparadas soluções experimentais dos corantes Acid Blue 40 e Acid Red 151, com concentrações equivalentes a 100 μg/mL e a estas foram adicionadas esferas com a levedura imobilizada a partir de uma suspensão 10% e gotas de células livres a partir de uma suspensão 2%. Os testes comparativos de remoção dos corantes foram analisados através de espectrofotômetros Ultravioleta- Visível e Infravermelho com Transformada de Fourier, com os quais foi possível determinar a porcentagem de remoção dos corantes das soluções, os valores das Absorbâncias Relativas que revelaram se o processo predominante na descoloração foi o da biossorção e/ou biodegradação, a quantidade de biomassa em miligramas (peso seco) necessária para fazer a remoção total da cor e também determinar as alterações moleculares ocorridas nas estruturas dos corantes após os tratamentos. Os resultados mostraram que a maior porcentagem de descoloração alcançada para o Acid Blue 40 foi de 61,7% após 360 horas de tratamento com 20 esferas com a levedura imobilizada e para o Acid Red 151 foi de 81,9% após 216 horas de tratamento também com 20 esferas com o microrganismo imobilizado. Através dos valores das Absorbâncias Relativas foi possível verificar que o processo predominante na remoção da cor do Acid Blue 40 com 72 horas de tratamento com 10 e 20 esferas com Saccharomyces cerevisiae imobilizada foi o da biossorção seguido da biodegradação e para o Acid Red 151 com esse mesmo tempo de tratamento e com a mesma quantidade de biomassa imobilizada foi o da biodegradação. A quantidade de biomassa imobilizada e livre... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This paper presents a comparative assessment of the biodegradative and biosorptive potential of the yeast Saccharomyces cerevisiae in textile dyes removal of effluents when in immobilized alginate and in free cells. Therefore, experimental solutions were prepared with concentrations of the dye Acid Blue 40 and Acid Red 151 equivalent to 100 mg/mL and those were added with beads containing the immobilized yeast from a 10% suspension and drops of free cells from a 2 % suspension. Comparative tests of dye removal were analyzed by UV-Visible spectrometers and Infrared Fourier Transform on which it was possible to determine the percentage of dye removal from the solutions, the values of Relatives Absorbances that the discoloration have been proved to predominant by biosorption and / or biodegradation, the amount of biomass in milligrams (dry weight) required for a complete color removal and also to determine the molecular changes occurring in the dye structures after the treatment. The results showed that the highest decolorization percentage achieved for Acid Blue 40 was 61.7% after 360 hours of treatment with 20 immobilized yeast beads and for the Acid Red 151 it was 81.9% after 216 hours of treatment with 20 beads also with immobilized microorganism. Through the values of Relatives Absorbances it was concluded that the predominant process in dye removal of Acid Blue 40 in 72 hours of treatment with 10 and 20 beads containing imobilized Saccharomyces cerevisiae was the biosorption followed by biodegradation and in Acid Red 151 with the same treatment time and the same amount of immobilized biomass it was the biodegradation. The amount of immobilized and free biomass to obtain total removal of Acid Blue 40 solution was 87 and 38 mg/mL, respectively, and to completely remove the Acid Red 151, the required amount of free and immobilized biomass was 64 and 2 mg/mL, respectively, which... (Complete abstract click electronic access below) / Mestre

Made available in DSpace on 2016-08-19T12:56:47Z (GMT). No. of bitstreams: 1 Dissertacao RAILSON DA CUNHA FERREIRA.pdf: 1000257 bytes, checksum: 27800981d5c5e7d5164de83e74ae726e (MD5) Previous issue date: 2014-04-30 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The adsorption is widely used for the treatment of textile effluents and with the high cost of conventional adsorbents search becoming more alternative adsorbents, efficient and cheaper. The maranhense clay treated with inorganic acid, in this study of hydrochloric acid, was applied to the removal of textile dyes crystal violet (CV) and turquoise blue (TB). We investigated the adsorptive effect of parameters such pH, temperature, concentration of dyes and contact time in the adsorption process as the kinetic, and thermodynamic parameters of isothermal adsorption. The adsorbent was characterized by analysis in the infrared (IR), X-ray diffraction (XRD), point of zero charge (PZC) and chemical composition analysis by X-ray fluorescence (XRF). The kinetic data were best represented by the kinetic model of pseudosecond order and the adsorption isotherms by the Sips isotherm model. The maximum adsorption capacity of the treated clay was 103.02 mg gˉ¹ for crystal violet and 97.91 mg gˉ¹for the turquoise blue. The thermodynamic parameters showed that the adsorption process is endothermic (ΔHºads positive), spontaneous and favorable (ΔG°ads negative) and also presented randomness of the system (ΔS⁰ads positive). The maranhense treated clay proved to be a good adsorbent for low cost, easy to purchase and can be used in the adsorption process. / A adsorção é bastante empregada no tratamento de efluentes têxteis e com o elevado custo dos adsorventes convencionais busca-se cada vez mais adsorventes alternativos, eficientes e mais baratos. A argila maranhense tratada com ácido inorgânico, no caso deste estudo o ácido clorídrico, foi aplicada na remoção dos corantes têxteis violeta cristal (VC) e azul turquesa (AT). Investigou-se o efeito adsortivo dos parâmetros tais como pH, temperatura, concentração dos corantes e tempo de contato no processo de adsorção, assim como os parâmetros cinéticos, isotérmicos e termodinâmicos de adsorção. O adsorvente foi caracterizado por análise na região do infravermelho (IR), difração de raios-X (XRD), ponto de carga zero (PCZ) e análise da composição química por fluorescência de raios-X (XRF). Os dados cinéticos foram melhores representados pelo modelo cinético de pseudo-segunda ordem e as isotermas de adsorção pelo modelo isotérmico de Sips. A capacidade máxima de adsorção da argila tratada foi de 103,02 mg gˉ¹ para o violeta cristal e 97,91 mg gˉ¹ para o azul turquesa. Os parâmetros termodinâmicos de adsorção mostraram que o processo é endotérmico (ΔHºads positivo), espontâneo e favorável (ΔGºads negativo) e apresentou também aleatoriedade do sistema (ΔSads positivo). A argila maranhense tratada se mostrou ser um bom adsorvente de baixo custo, de fácil aquisição e que pode ser empregada no processo de adsorção.

Made available in DSpace on 2016-08-19T12:56:47Z (GMT). No. of bitstreams: 1 DISSERTACAO ROBERTO PEREIRA DA SILVA.pdf: 972230 bytes, checksum: c95b4a45f2167cc6018586ac7f1e5b83 (MD5) Previous issue date: 2014-08-29 / FUNDAÇÃO DE AMPARO À PESQUISA E AO DESENVOLVIMENTO CIENTIFICO E TECNOLÓGICO DO MARANHÃO / The adsorption technique has been widely used in the treatment of textile effluents, particularly in the adsorption of dyes from various chemical classes using alternative materials and low cost. In this study we investigated the adsorptive potential of a mineral clay (zeolite maranhense) is treated with hydrochloric acid in removal of cationic textile dyes crystal violet (CV) and methylene blue (MB) in an aqueous medium. For both effects were studied parameters such as pH, temperature and contact time, and studies of the kinetic, and thermodynamic parameters of isothermal adsorption. The characterization of the adsorbent occurred by IR, XRD, pHPCZ, surface area (BET), micropore volume and average pore diameter. The kinetic data were best represented by the Elovich kinetic model of the adsorption isotherms by Freundlich isotherm model. The maximum adsorption capacity of the treated zeolite was 34, 71 and 77, 11 mg gˉ¹ for the crystal violet and methylene blue, respectively. The thermodynamic parameters showed that the adsorption process is exothermic (negative ΔHads) and spontaneous with positive values ΔG and ΔS of adsorption negative. The treated zeolite shows good adsorptive capacity for the studied dye material as compared to other literature as well as lower cost. / A técnica de adsorção tem sido bastante empregada no tratamento de efluentes têxteis, sobretudo na adsorção de corantes das mais diversas classes químicas utilizando materiais alternativos e de baixo custo. Nesse estudo investigou-se o potencial adsortivo de um argilomineral (zeólita maranhense) tratada com ácido clorídrico na remoção dos corantes têxteis catiônicos violeta Cristal (VC) e azul de metileno (AM) em meio aquoso. Para tanto foram estudados os efeitos de parâmetros tais como: pH, temperatura e tempo de contato, além de estudos dos parâmetros cinéticos, isotérmicos e termodinâmicos de adsorção. A caracterização do adsorvente se deu por IR, XRD, pHPCZ, área superficial (BET), volume de microporos e diâmetro médio de poros. Os dados cinéticos foram melhores representados pelo modelo cinético de Elovich, as isotermas de adsorção pelo modelo isotérmico de Freundlich. A capacidade máxima de adsorção da zeólitas tratada foi de 34, 71 e 77, 11 mg gˉ¹ para o violeta cristal e azul de metileno, respectivamente. Os parâmetros termodinâmicos de adsorção mostraram que o processo é exotérmico (ΔHads negativo), espontâneo e favorável com valores de ΔG e ΔS de adsorção negativos. A zeólita tratada apresenta boa capacidade de adsorção para os corantes estudados quando comparado com outros materiais da literatura além do menor custo.

Reactive Black 5 and Procion Red MX 5B, an azo and anthraquinone dye repectively were decoulorized by mean of microorganisms growing on wood chips. The process consisted of three reactors, two anaerobic reactors and one aerobic reactor. The anaerobic process was used in order to make it possible to break the nitrogen bond of the azo group, (-N=N-) and the aerobic one to increase the possibility for the degradation of possible intermediates. After pumping wastewater through the system it was shown that mixtures or Reactive Black 5 and Procion Red MX 5B were efficiently decolourised at 50 mg/l as well as 200 mg/l of each of the dyes.