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In this master thesis, the feasibility of Fenton-oxidation for the decolorization of reactive dyed cotton is investigated as a potentially environmental-friendly preparatory treatment for mechanical/chemical recycling. Raw, knitted cotton is dyed with a black and a blue dye, whereafter preliminary tests are performed to investigate the influence of increasing Fenton- solution concentrations and different iron-sources on the efficiency of the discoloration, without carrying out complete optimization of the process-parameters. Based on the preliminary test-results, Fenton-treatments of the reactive-dyed cotton are upscaled, with discoloration efficiencies of 62 and 73% (for the black- and blue-dyed cotton respectively). Thermal analysis (TGA, DSC and FTIR) and mechanical analysis (tensile tests and shredding of the fabric) of the upscaled treated samples are performed, and the results indicate no major alterations of the main cellulosic structure of the cotton fibers. However, besides the degradation of the dye-molecules, also some oxidation (and therefore damage) of the cellulose-chains of the cotton fibers occurs, leading to reduced mechanical properties. Although this facilitates the mechanical recycling process, it possibly also reduces the quality of the re-spun yarns. Nevertheless, the Fenton-oxidation in the context of decolorization of reactive-dyed cotton forms an interesting future research-topic with many opportunities and prospects for increasing the efficiency and sustainability of the recycling process, and therefor increasing the sustainability of the textile industry in general.

In this master thesis, the feasibility of Fenton-oxidation for the decolorization of reactive dyed cotton is investigated as a potentially environmental-friendly preparatory treatment for mechanical/chemical recycling. Raw, knitted cotton is dyed with a black and a blue dye, whereafter preliminary tests are performed to investigate the influence of increasing Fenton- solution concentrations and different iron-sources on the efficiency of the discoloration, without carrying out complete optimization of the process-parameters. Based on the preliminary test-results, Fenton-treatments of the reactive-dyed cotton are upscaled, with discoloration efficiencies of 62 and 73% (for the black- and blue-dyed cotton respectively). Thermal analysis (TGA, DSC and FTIR) and mechanical analysis (tensile tests and shredding of the fabric) of the upscaled treated samples are performed, and the results indicate no major alterations of the main cellulosic structure of the cotton fibers. However, besides the degradation of the dye-molecules, also some oxidation (and therefore damage) of the cellulose-chains of the cotton fibers occurs, leading to reduced mechanical properties. Although this facilitates the mechanical recycling process, it possibly also reduces the quality of the re-spun yarns. Nevertheless, the Fenton-oxidation in the context of decolorization of reactive-dyed cotton forms an interesting future research-topic with many opportunities and prospects for increasing the efficiency and sustainability of the recycling process, and therefor increasing the sustainability of the textile industry in general.

Background: As a company it is more important than ever to consider the environmental sustainability aspect within the whole supply chain and all the stakeholders. Studies show that people's concerns about environmental sustainability increases and will continue to grow in the future. The wet dyeing process is the part of the textile production that consists of liquor and contains three main steps which are pretreatment, coloration and finishing. This process is presented as the most water, energy and chemicals consuming process within the textile industry and because of that, it is important to investigate it to be able to improve the environmental sustainability. Purpose: The purpose of the thesis is to increase the understanding of IKEA’s suppliers' current usage of water, energy and chemicals within the wet dyeing process. Followed by an identification of opportunities for improvements in the wet dyeing process, aiming to become more environmentally sustainable. Method: Through interviews with two suppliers, information regarding IKEA’s current wet dyeing processes will be collected. After that, data from relevant theoretical sources will be collected to analyze possible improvements of methods and colorants that can be relevant for IKEA as well as other companies within the textile industry to implement. Conclusion: For research question 1, the researchers reach the conclusion that IKEA’s supplier number one has a more environmentally sustainable wet dyeing process compared to the second supplier.. A conclusion is nevertheless drawn that improvements within both suppliers wet dyeing processes should be considered to become more environmentally sustainable. For research question 2, the researchers come to the conclusion that Spray dyeing is the best alternative method to implement for improving environmental sustainability within the wet dyeing process. The researchers also recommend companies to actively become a part of the development of bacterial colorant

Background: As a company it is more important than ever to consider the environmental sustainability aspect within the whole supply chain and all the stakeholders. Studies show that people's concerns about environmental sustainability increases and will continue to grow in the future. The wet dyeing process is the part of the textile production that consists of liquor and contains three main steps which are pretreatment, coloration and finishing. This process is presented as the most water, energy and chemicals consuming process within the textile industry and because of that, it is important to investigate it to be able to improve the environmental sustainability. Purpose: The purpose of the thesis is to increase the understanding of IKEA’s suppliers' current usage of water, energy and chemicals within the wet dyeing process. Followed by an identification of opportunities for improvements in the wet dyeing process, aiming to become more environmentally sustainable. Method: Through interviews with two suppliers, information regarding IKEA’s current wet dyeing processes will be collected. After that, data from relevant theoretical sources will be collected to analyze possible improvements of methods and colorants that can be relevant for IKEA as well as other companies within the textile industry to implement. Conclusion: For research question 1, the researchers reach the conclusion that IKEA’s supplier number one has a more environmentally sustainable wet dyeing process compared to the second supplier.. A conclusion is nevertheless drawn that improvements within both suppliers wet dyeing processes should be considered to become more environmentally sustainable. For research question 2, the researchers come to the conclusion that Spray dyeing is the best alternative method to implement for improving environmental sustainability within the wet dyeing process. The researchers also recommend companies to actively become a part of the development of bacterial colorant

Reactive dyes are widely used in the dyeing of cellulosic fiber mainly due to their high fastnesses and wide range of colors. The dyeing process carried out with this type of dyes requires the addition of high amounts of salt and the presence of an alkaline medium, generating wastewater generally characterized by its high coloration and salinity. The conventional treatments currently applied for the treatment of these wastewaters allow meet with discharge regulations, but do not allow the water to be reused in new dyeing processes. In order to reuse water in new production processes, advanced purification processes must be applied. To the best of our knowledge, the reuse of water after electrochemical treatments has been successfully implemented in the dyeing process, making it possible to reduce 100% of the dyeing water and up to 72% of the salts. However, few studies have evaluated the reuse of the treated effluents in the washing processes after the dyeing step. In order to know the effect of the presence of salts in the washing water of the post-dyeing processes, in this work 3 reactive dyes have been selected, which have been studied both in monochromies and in trichromies. For each of them, the maximum concentration of salt that the treated effluent can contain to be reused was selected. The fabrics carried out with reused water were compared in terms of color difference with references made with fresh water. It was found that the maximum salt concentration varies between 5 g/l and 20 g/l depending on the dye. It should be noted that the concentration of dye used in the dyeing process is not a key factor in the effect of the presence of residual salt in the subsequent washing stages

The consumption of dyes is increasing worldwide in line with the increase of population and demand for clothes and other colored products. However, the efficiency of dyeing processes is still poor and results in large amounts of colored effluents. It is desired to develop a portfolio of enzymes which can be used for the treatment of colored wastewaters. Herein, we used genome sequence information to discover a dye-decolorizing peroxidase (DyP) from Pseudomonas fluorescens Pf-01. Two genes putatively encoding for DyPs were identified in the respective genome and cloned for expression in Escherichia coli, of which one (Pf DyP B2) could be overexpressed as a soluble protein. Pf DyP B2 shows some typical features known for DyPs which includes the ability to convert dyes at the expense of hydrogen peroxide. Interestingly, t-butyl hydroperoxide could be used as an alternative substrate to hydrogen peroxide. Immobilization of Pf DyP B2 in calcium-alginate beads resulted in a significant increase in stability: Pf DyP B2 retains 80% of its initial activity after 2 h incubation at 50◦ C, while the soluble enzyme is inactivated within minutes. Pf DyP B2 was also tested with aniline and ethyl diazoacetate as substrates. Based on GC-MS analyses, 30% conversion of the starting material was achieved after 65 h at 30◦ C. Importantly, this is the first report of a DyP-catalyzed insertion of a carbene into an N-H bond.

The consumption of dyes is increasing worldwide in line with the increase of population and demand for clothes and other colored products. However, the efficiency of dyeing processes is still poor and results in large amounts of colored effluents. It is desired to develop a portfolio of enzymes which can be used for the treatment of colored wastewaters. Herein, we used genome sequence information to discover a dye-decolorizing peroxidase (DyP) from Pseudomonas fluorescens Pf-01. Two genes putatively encoding for DyPs were identified in the respective genome and cloned for expression in Escherichia coli, of which one (Pf DyP B2) could be overexpressed as a soluble protein. Pf DyP B2 shows some typical features known for DyPs which includes the ability to convert dyes at the expense of hydrogen peroxide. Interestingly, t-butyl hydroperoxide could be used as an alternative substrate to hydrogen peroxide. Immobilization of Pf DyP B2 in calcium-alginate beads resulted in a significant increase in stability: Pf DyP B2 retains 80% of its initial activity after 2 h incubation at 50◦ C, while the soluble enzyme is inactivated within minutes. Pf DyP B2 was also tested with aniline and ethyl diazoacetate as substrates. Based on GC-MS analyses, 30% conversion of the starting material was achieved after 65 h at 30◦ C. Importantly, this is the first report of a DyP-catalyzed insertion of a carbene into an N-H bond.

Dyes are classified as one of the major pollutants of water. They have negative impacts not only on environment but also on human health. In fact, wastewater that contains these harmful substances requires many types of treatments. Therefore, alternative methods and adsorption agents are needed. Herein, we propose to evaluate the decolorization of methylene blue (MB) and methyl orange (MO) as two models of soluble dyes from water using chitin and chitosan-graft-polyacrylamide. Furthermore, the applicability of these biomacromolecules as alternative adsorption agents, their sticking probability and desorption were also examined. Experimental parameters such as dye concentration, contact time, pH solution, adsorbent dosage and temperature were thoroughly examined for the grafted chitosan and chitin. The activation energy (Ea) and the thermodynamic variables (i. e., standard Gibb's free energy (D G0), standard enthalpy (D H0), and standard entropy (D S0)) were determined using the Van't Hoff and Arrhenius equations. The sticking probability (S*) model for MB and MO removal by chitin and the chitosan derivative demonstrated that both dyes were successfully removed under the proposed conditions. Desorption studies of MB and MO showed the reusability of both materials, suggesting their application for removing dyes from aqueous solution.

The consumption of dyes is increasing worldwide in line with the increase of population and demand for clothes and other colored products. However, the e ciency of dyeing processes is still poor and results in large amounts of colored e uents. It is desired to develop a portfolio of enzymes which can be used for the treatment of colored wastewaters. Herein, we used genome sequence information to discover a dye-decolorizing peroxidase (DyP) from Pseudomonas fluorescens Pf-01. Two genes putatively encoding for DyPs were identified in the respective genome and cloned for expression in Escherichia coli, of which one (PfDyP B2) could be overexpressed as a soluble protein. PfDyP B2 shows some typical features known for DyPs which includes the ability to convert dyes at the expense of hydrogen peroxide. Interestingly, t-butyl hydroperoxide could be used as an alternative substrate to hydrogen peroxide. Immobilization of PfDyP B2 in calcium-alginate beads resulted in a significant increase in stability: PfDyP B2 retains 80% of its initial activity after 2 h incubation at 50 °C, while the soluble enzyme is inactivated within minutes. PfDyP B2 was also tested with aniline and ethyl diazoacetate as substrates. Based on GC-MS analyses, 30% conversion of the starting material was achieved after 65 h at 30 °C. Importantly, this is the first report of a DyP-catalyzed insertion of a carbene into an N-H bond.

Dyes are classified as one of the major pollutants of water. They have negative impacts not only on environment but also on human health. In fact, wastewater that contains these harmful substances requires many types of treatments. Therefore, alternative methods and adsorption agents are needed. Herein, we propose to evaluate the decolorization of methylene blue (MB) and methyl orange (MO) as two models of soluble dyes from water using chitin and chitosan-graft-polyacrylamide. Furthermore, the applicability of these biomacromolecules as alternative adsorption agents, their sticking probability and desorption were also examined. Experimental parameters such as dye concentration, contact time, pH solution, adsorbent dosage and temperature were thoroughly examined for the grafted chitosan and chitin. The activation energy (Ea) and the thermodynamic variables (i. e., standard Gibb's free energy (D G0), standard enthalpy (D H0), and standard entropy (D S0)) were determined using the Van't Hoff and Arrhenius equations. The sticking probability (S*) model for MB and MO removal by chitin and the chitosan derivative demonstrated that both dyes were successfully removed under the proposed conditions. Desorption studies of MB and MO showed the reusability of both materials, suggesting their application for removing dyes from aqueous solution.

Dyes are classified as one of the major pollutants of water. They have negative impacts not only on environment but also on human health. In fact, wastewater that contains these harmful substances requires many types of treatments. Therefore, alternative methods and adsorption agents are needed. Herein, we propose to evaluate the decolorization of methylene blue (MB) and methyl orange (MO) as two models of soluble dyes from water using chitin and chitosan-graft-polyacrylamide. Furthermore, the applicability of these biomacromolecules as alternative adsorption agents, their sticking probability and desorption were also examined. Experimental parameters such as dye concentration, contact time, pH solution, adsorbent dosage and temperature were thoroughly examined for the grafted chitosan and chitin. The activation energy (Ea) and the thermodynamic variables (i. e., standard Gibb's free energy (D G0), standard enthalpy (D H0), and standard entropy (D S0)) were determined using the Van't Hoff and Arrhenius equations. The sticking probability (S*) model for MB and MO removal by chitin and the chitosan derivative demonstrated that both dyes were successfully removed under the proposed conditions. Desorption studies of MB and MO showed the reusability of both materials, suggesting their application for removing dyes from aqueous solution.

The consumption of dyes is increasing worldwide in line with the increase of population and demand for clothes and other colored products. However, the e ciency of dyeing processes is still poor and results in large amounts of colored e uents. It is desired to develop a portfolio of enzymes which can be used for the treatment of colored wastewaters. Herein, we used genome sequence information to discover a dye-decolorizing peroxidase (DyP) from Pseudomonas fluorescens Pf-01. Two genes putatively encoding for DyPs were identified in the respective genome and cloned for expression in Escherichia coli, of which one (PfDyP B2) could be overexpressed as a soluble protein. PfDyP B2 shows some typical features known for DyPs which includes the ability to convert dyes at the expense of hydrogen peroxide. Interestingly, t-butyl hydroperoxide could be used as an alternative substrate to hydrogen peroxide. Immobilization of PfDyP B2 in calcium-alginate beads resulted in a significant increase in stability: PfDyP B2 retains 80% of its initial activity after 2 h incubation at 50 °C, while the soluble enzyme is inactivated within minutes. PfDyP B2 was also tested with aniline and ethyl diazoacetate as substrates. Based on GC-MS analyses, 30% conversion of the starting material was achieved after 65 h at 30 °C. Importantly, this is the first report of a DyP-catalyzed insertion of a carbene into an N-H bond.

Microencapsulations protects the dye molecule from secondary reactions and release until contact with the fiber, triggered by stimuli. The procedure was performed using poly(lactic-acid-co-glycolic-acid), PLGA, and polyvinyl alcohol, PVA, and was confirmed via optical microscopy. UV-VIS spectroscopy assessed the efficiency of the encapsulation; and, the mathematical models of Korsmeyer-Peppas and Higuchi quantified controlled-release of dye. The microcapsules formed a core-shell structure, with a perfect sphere shape and homogeneous size. The release adjustments yielded the apparent diffusion coefficient, Postprint (published version)

Problematika levného a účinného čištění odpadních vod produkovaných při výrobě a aplikaci vodorozpustných barviv je celosvětově intenzívně zkoumána, protože biologická odbouratelnost mnoha syntetických barviv je běžnými postupy čištění používanými v biologických čistírnách odpadních vod velmi omezená. Výsledkem čištění vod kontaminovaných syntetickými barvivy pak často bývá voda, která sice může splňovat požadavky dané kanalizačním řádem, ale její znečištění definované chemickou spotřebou kyslíku (CHSKCr) a především její zbarvení jsou odlišné od přírodního toku, do kterého je vypouštěna. Tento fakt je negativně vnímán veřejností a může vést k tomu, že veřejné mínění se staví do opozice proti provozovatelům výroby a aplikace zmiňovaných barviv. Univerzita Pardubice vyvinula levnou metodu účinného odstraňování kyselých barviv z kontaminovaných vod chemisorpcí na iontové kapaliny a hlinité nebo železité koagulanty. Chemisorpcí separovaná barviva byla následně testována v receptuře na bázi neionogenních tenzidů při laboratorní přípravě závěsných sanitárních prostředků a airfreshenerů., The issue of the inexpensive and effective removal of anionic dyes from textile wastewater is intensively studied because the biodegradability of synthetic dyes in standard biological wastewater treatment plants is very limited. The result of treatment of waste water containing dyes is often water, which may well satisfy the requirements of the sewerage system, but its color and chemical oxygen demand parameter (CODCr) is evidently different from the natural stream into which it is discharged. This fact is negatively perceived by the public and it can lead to the situation that public opinion is in opposition to the producers and users of synthetic dyes. University of Pardubice now developed an inexpensive method for the chemisorption of hydrolyzed reactive dyes from spent dyeing baths used for cotton dyeing using ionic liquids and/ or aluminum-based coagulants. The separated dyes were tested for coloring of products based on nonionic surfactants, especially for WC block and airfreshener formula composition.

This work presents precipitation and removal of hydrolyzed reactive dyes by action of liquid ion exchangers in co-action of inorganic flocculant. After addition of cationic surfactant and aqueous aluminium chloride the precipitation occurs and practically decolorized aqueous phase is obtained. The treated water was completely decolorized and purified by addition of powdered charcoal., Článek popisuje účinnost srážení a následného odstranění hydrolyzovaných reaktivních barviv působením kapalných iontoměničů za spolupůsobení anorganických flokulantů. Přídavek kationaktivního tenzidu a chloridu hlinitého vede ke vzniku sraženiny, po jejímž odstranění dojde k odbarvení vzniklých filtrátů. Závěrečné dočištění se provádí adsorpcí na práškové aktivní uhlí.

The chemical recycling of cellulosic fibres may represent a next-generation fibre–fibre recycling system for cotton textiles, though remaining challenges include how to accommodate fibre blends, dyes, wrinkle-free finishes, and other impurities from finishing. These challenges may disrupt the regeneration process steps and reduce the fibre quality. This study examines the impact on regenerated viscose fibre properties of a novel alkaline/acid bleaching sequence to strip reactive dyes and dimethyloldihydroxyethyleneureas (DMDHEU) wrinkle-free finish from cotton textiles. Potentially, such a bleaching sequence could advantageously be integrated into the viscose process, reducing the costs and environmental impact of the product. The study investigates the spinning performance and mechanical properties (e.g., tenacity and elongation) of the regenerated viscose fibres. The alkaline/acid bleaching sequence was found to strip the reactive dye and DMDHEU wrinkle-free finish from the cotton fabric, so the resulting pulp could successfully be spun into viscose fibres, though the mechanical properties of these fibres were worse than those of commercial viscose fibres. This study finds that reactive dyes and DMDHEU wrinkle-free finish affect the viscose dope quality and the regeneration performance. The results might lead to progress in overcoming quality challenges in cellulosic chemical recycling.

The chemical recycling of cellulosic fibres may represent a next-generation fibre–fibre recycling system for cotton textiles, though remaining challenges include how to accommodate fibre blends, dyes, wrinkle-free finishes, and other impurities from finishing. These challenges may disrupt the regeneration process steps and reduce the fibre quality. This study examines the impact on regenerated viscose fibre properties of a novel alkaline/acid bleaching sequence to strip reactive dyes and dimethyloldihydroxyethyleneureas (DMDHEU) wrinkle-free finish from cotton textiles. Potentially, such a bleaching sequence could advantageously be integrated into the viscose process, reducing the costs and environmental impact of the product. The study investigates the spinning performance and mechanical properties (e.g., tenacity and elongation) of the regenerated viscose fibres. The alkaline/acid bleaching sequence was found to strip the reactive dye and DMDHEU wrinkle-free finish from the cotton fabric, so the resulting pulp could successfully be spun into viscose fibres, though the mechanical properties of these fibres were worse than those of commercial viscose fibres. This study finds that reactive dyes and DMDHEU wrinkle-free finish affect the viscose dope quality and the regeneration performance. The results might lead to progress in overcoming quality challenges in cellulosic chemical recycling.

The chemical recycling of cellulosic fibres may represent a next-generation fibre–fibre recycling system for cotton textiles, though remaining challenges include how to accommodate fibre blends, dyes, wrinkle-free finishes, and other impurities from finishing. These challenges may disrupt the regeneration process steps and reduce the fibre quality. This study examines the impact on regenerated viscose fibre properties of a novel alkaline/acid bleaching sequence to strip reactive dyes and dimethyloldihydroxyethyleneureas (DMDHEU) wrinkle-free finish from cotton textiles. Potentially, such a bleaching sequence could advantageously be integrated into the viscose process, reducing the costs and environmental impact of the product. The study investigates the spinning performance and mechanical properties (e.g., tenacity and elongation) of the regenerated viscose fibres. The alkaline/acid bleaching sequence was found to strip the reactive dye and DMDHEU wrinkle-free finish from the cotton fabric, so the resulting pulp could successfully be spun into viscose fibres, though the mechanical properties of these fibres were worse than those of commercial viscose fibres. This study finds that reactive dyes and DMDHEU wrinkle-free finish affect the viscose dope quality and the regeneration performance. The results might lead to progress in overcoming quality challenges in cellulosic chemical recycling.

Disertační práce je zaměřená na studium účinnosti odstraňování ve vodě rozpustných barviv, konkrétně kyselých azobarviv, se zaměřením na reaktivní barviva z modelových odpadních vod použitím kvartérních fosfoniových resp. amoniových solí, a/nebo jejich kombinacemi s anorganickými koagulanty, jakými jsou hydratované formy síranu hlinitého a železitého. Vedle toho bylo provedeno ověření možnosti aplikace pomocného filtračního materiálu (práškového uhličitanu vápenatého) pro snadné oddělování iontových párů vznikajících reakcí testovaných kyselých barviv s kvartérními amoniovými nebo fosfoniovými solemi. Cílem bylo dosáhnout maximální účinnosti čištění kontaminovaných vod s použitím jednoduché a rychlé metody, která by umožnila potenciální využití separovaného kalu., This thesis is focused on the study of the effectiveness of the removal of water-soluble dyes, namely acid azo-dyes, especially reactive dyes and from the model wastewater using by tetrasubstituted phosphonium respectively ammonium salts or their combination with inorganic coagulants, which are hydrated forms of aluminum sulfate or ferric sulfate. In addition there was tested verification of possibility of application of the auxiliary filter material (powdered calcium carbonate) for easy separation of ionic pairs produced by reaction of acid dyes with quaternary ammonium or phosphonium salts. The aim of this thesis was to explore simple and cheap method for effective wastewater treatment with potencial utilization of produced sludge., Fakulta chemicko-technologická

The electrochemical behavior of different carbon-based electrodes with and without nanoparticles of platinum electrochemically dispersed on their surface has been studied. Among others, reduced graphene oxide based electrodes was used to determine the best conditions for the decolorization/degradation of the reactive dye C.I. Reactive Orange 4 in sulfuric medium. Firstly, the electrochemical behavior was evaluated by cyclic voltammetry. Secondly, different electrolyses were performed using two cell configurations: cell with anodic and cathodic compartments separated (divided configuration) and without any separation (undivided configuration). The best results were obtained when reduced graphene oxide based anodes were used. The degree of decolorization was monitored by spectroscopic methods and high performance liquid chromatography. It was found that all of them followed pseudofirst order kinetics. When reduced graphene oxide-based electrodes coated with dispersed platinum by alternate current methods electrodes were used, the lowest energy consumption and the higher decolorization kinetics rate were obtained. Scanning Electronic Microscopy was used to observe the morphological surface differences.

The electrochemical behavior of different carbon-based electrodes with and without nanoparticles of platinum electrochemically dispersed on their surface has been studied. Among others, reduced graphene oxide based electrodes was used to determine the best conditions for the decolorization/degradation of the reactive dye C.I. Reactive Orange 4 in sulfuric medium. Firstly, the electrochemical behavior was evaluated by cyclic voltammetry. Secondly, different electrolyses were performed using two cell configurations: cell with anodic and cathodic compartments separated (divided configuration) and without any separation (undivided configuration). The best results were obtained when reduced graphene oxide based anodes were used. The degree of decolorization was monitored by spectroscopic methods and high performance liquid chromatography. It was found that all of them followed pseudofirst order kinetics. When reduced graphene oxide-based electrodes coated with dispersed platinum by alternate current methods electrodes were used, the lowest energy consumption and the higher decolorization kinetics rate were obtained. Scanning Electronic Microscopy was used to observe the morphological surface differences.

The Ph.D. Thesis represents a complex study of several areas: the first is related to the optimization of dyeing cotton textiles with direct and reactive dyes, the second to the physical and chemical modification of natural waste materials (fly ash), the third to the possibility of applying modified natural adsorbent in the process of dye removal from the dyeing effluent, and finally, the fourth to the recirculation of discolored waste water back into the new textile dyeing process. Based on the results obtained, it can be concluded that the modified waste fly ash is an efficient adsorbent for the removal of reactive and direct dyes or combinations of two reactive or two direct dyes from aqueous solutions, with a reasonable tendency of the application under industrial conditions. Also, it is possible to reuse so discolored water, under industrial conditions, for the new textile dyeing. The study revealed the following results: 1) Optimization of cotton dyeing with Direct Blue 85 or Direct Red 79, showed savings of electrolytes, leveling agents, defoamers and temperature of dyeing; 2) Optimization of cotton dyeing with the mixture of Direct Blue 85 and Direct Red 79, had savings of electrolytes, leveling agents, defoamers and temperature of dyeing; 3) Optimization of cotton dyeing with Reactive Blue 222 or Reactive Red 194, demonstrated savings in the quantity of electrolyte, alkalis, defoamer, leveling agents, time and temperature of dyeing; 4) Optimization of cotton dyeing with the mixture of Reactive Blue 222 and Reactive Red 194, led to savings in electrolytes, defoamer, leveling agents and dyeing time; 5) Modification of the native fly ash was successfully applied in order to obtain the structure which is more effective to retain dye molecules by physical and chemical interactions; 6) X-ray powder diffraction showed that the dominant phase of the analyzed sample was calcium carbonate, followed by graphite, quartz and carbon; 7) Modified ash is relatively fine bu

The electrochemical decolorization of Reactive Orange 16 in a chloride containing solution was studied using a dimensionally stable Ti/PtOx anode. Different reaction parameters, agitation speed, applied current, sodium chloride concentration, and dye concentration were varied and the optimum electrolysis conditions were suggested. Hypochlorous acid was suggested to be the active species in the electrochemical decolorization. Moreover, the reaction was studied using UV-Vis spectrophotometry, high-pressure liquid chromatography (HPLC), total organic carbon (TOC) and total nitrogen (TN) analyses.

This study focused on the advanced oxidation of the hetero bi-functional reactive dye Sumifix Supra Yellow 3RF (CI Reactive Yellow 145) using dark Fenton and photo-Fenton conditions in a lab-scale experiment. A 2(3) factorial design was used to evaluate the effects of the three key factors: temperature, Fe(II) and H2O2 concentrations, for a dye concentration of 250 mg L-1 with chemical oxygen demand (COD) of 172 mg L-1 O-2 at pH = 3. The response function was the COD reduction. This methodology lets us find the effects and interactions of the studied variables and their roles in the efficiency of the treatment process. In the optimization, the correlation coefficients for the model (R-2) were 0.948 and 0.965 for Fenton and photo-Fenton treatments, respectively. Under optimized reaction conditions: pH = 3, temperature = 298 K, [H2O2] = 11.765 mM and [Fe(II)] = 1.075 mM; 60 min of treatment resulted in a 79% and 92.2% decrease in COD, for the dye taken as the model organic compound, after Fenton and photo-Fenton treatments, respectively, Postprint (author’s final draft)

The electrochemical decolorization of Reactive Orange 16 in a chloride containing solution was studied using a dimensionally stable Ti/PtOx anode. Different reaction parameters, agitation speed, applied current, sodium chloride concentration, and dye concentration were varied and the optimum electrolysis conditions were suggested. Hypochlorous acid was suggested to be the active species in the electrochemical decolorization. Moreover, the reaction was studied using UV-Vis spectrophotometry, high-pressure liquid chromatography (HPLC), total organic carbon (TOC) and total nitrogen (TN) analyses.

Halotolerant strains of Bacillus amyloliquefaciens were isolated from salt spring in Ovca spa located in Republic of Serbia. Strains exhibit robust spore laccase with high temperature optimum of 65 degrees C while pH optimum is wide and substrate dependant. Ability to oxidize azo dyes was demonstrated. Under optimized conditions more than 85% removal of Congo red dye was achieved at pH 5.7. Substantial resistance to inhibition by high concentration of chloride ions was observed and tolerance of some commonly used cosolvents shows that applicability of these laccases goes beyond decolorization of textile effluents. (C) 2014 Elsevier Ltd. All rights reserved.

Halotolerant strains of Bacillus amyloliquefaciens were isolated from salt spring in Ovca spa located in Republic of Serbia. Strains exhibit robust spore laccase with high temperature optimum of 65 degrees C while pH optimum is wide and substrate dependant. Ability to oxidize azo dyes was demonstrated. Under optimized conditions more than 85% removal of Congo red dye was achieved at pH 5.7. Substantial resistance to inhibition by high concentration of chloride ions was observed and tolerance of some commonly used cosolvents shows that applicability of these laccases goes beyond decolorization of textile effluents.

Halotolerant strains of Bacillus amyloliquefaciens were isolated from salt spring in Ovca spa located in Republic of Serbia. Strains exhibit robust spore laccase with high temperature optimum of 65 degrees C while pH optimum is wide and substrate dependant. Ability to oxidize azo dyes was demonstrated. Under optimized conditions more than 85% removal of Congo red dye was achieved at pH 5.7. Substantial resistance to inhibition by high concentration of chloride ions was observed and tolerance of some commonly used cosolvents shows that applicability of these laccases goes beyond decolorization of textile effluents. (C) 2014 Elsevier Ltd. All rights reserved.

Halotolerant strains of Bacillus amyloliquefaciens were isolated from salt spring in Ovca spa located in Republic of Serbia. Strains exhibit robust spore laccase with high temperature optimum of 65 degrees C while pH optimum is wide and substrate dependant. Ability to oxidize azo dyes was demonstrated. Under optimized conditions more than 85% removal of Congo red dye was achieved at pH 5.7. Substantial resistance to inhibition by high concentration of chloride ions was observed and tolerance of some commonly used cosolvents shows that applicability of these laccases goes beyond decolorization of textile effluents. (C) 2014 Elsevier Ltd. All rights reserved.

Halotolerant strains of Bacillus amyloliquefaciens were isolated from salt spring in Ovca spa located in Republic of Serbia. Strains exhibit robust spore laccase with high temperature optimum of 65 degrees C while pH optimum is wide and substrate dependant. Ability to oxidize azo dyes was demonstrated. Under optimized conditions more than 85% removal of Congo red dye was achieved at pH 5.7. Substantial resistance to inhibition by high concentration of chloride ions was observed and tolerance of some commonly used cosolvents shows that applicability of these laccases goes beyond decolorization of textile effluents.

Halotolerant strains of Bacillus amyloliquefaciens were isolated from salt spring in Ovca spa located in Republic of Serbia. Strains exhibit robust spore laccase with high temperature optimum of 65 degrees C while pH optimum is wide and substrate dependant. Ability to oxidize azo dyes was demonstrated. Under optimized conditions more than 85% removal of Congo red dye was achieved at pH 5.7. Substantial resistance to inhibition by high concentration of chloride ions was observed and tolerance of some commonly used cosolvents shows that applicability of these laccases goes beyond decolorization of textile effluents. (C) 2014 Elsevier Ltd. All rights reserved.

Les superfícies hidrofòbiques artificials són de gran interès en una àmplia gamma d’aplicacions industrials gràcies a les seves propietats d’autoneteja, anticontaminació biològica, antifongs, antiadherència i anticorrosió, entre d’altres. En la indústria tèxtil, són de gran interès materials amb propietats capaces de repel·lir l’aigua i compostos oliosos, ja que poden ser molt útils per a roba esportiva especial, tèxtils per a la llar com ara catifes o mobles entapissats, paraigües, etc. Seguint la trajectòria del nostre grup, hem sintetitzat colorants reactius amb diferents centres cromàtics que contenen a la seva estructura llargues cadenes polifluorades i grups funcionals que permeten el seu ancoratge sobre una superfície de cotó o vidre, de manera que hem obtingut nous materials hidrofòbics acolorits. Per tal d’estudiar la hidrofobicitat dels materials obtinguts, hem realitzat mesures de l’angle de contacte d’una gota d’aigua dipositada a la superfície de les teles tenyides i sobre vidres recoberts amb els nostres colorants sintetitzats. S’han obtingut angles més grans de 150º, en el cas dels teixits tenyits, la qual cosa demostra que són superhidrofòbics.Paraules clau: Colorant reactiu, fluor, cadenes polifluorades, hidrofobicitat., Artificial hydrophobic surfaces have a great potential in a wide range of industrial applications owing to their self-cleaning, anti-biofouling, anti-fogging, anti-sticking, anti-corrosion and anti-contamination properties. Equipment for fibers and textiles with hydrophobic properties is of high interest for fabrics with water, oil or soil repellent properties, e.g. for special sports clothes, home textiles like carpets or upholstered furniture, and some outdoor materials, such as umbrellas. Continuing along the line of research of our group, functional reactive dyes with different chromatic cores have been prepared with long polyfluorinated chains in their structure, and functional groups that allow their grafting on a cotton fabric surface or on glass, obtaining new colored hydrophobic materials. Contact angle measurements have been made of a droplet of water on the surface of stained fabrics and on glass coated with our new compounds. Angles higher than 150º have been obtained on the stained fabrics, proving that they are superhydrophobics.Keywords: Reactive dye, fluorine, polyfluorinated chains, hydrophobicity.

Tato disertační práce se zabývá mikroenkapsulací kyselého a reaktivního barviva do liposomních systémů tvořených lecitinem a tenzidem a aplikací této formy barviva při barvení chromočiněných usní. V teoretické části jsou shrnuty základní teoretické poznatky zaměřené na barvení chromočiněných usní. Další část je zaměřena na studium mikroenkapsulační technologie, techniky a podmínky přípravy kapsle, možností použití fofolipidových liposomů při barvení proteinových substrátů. V experimentální části jsou popsány postupy přípravy liposomů sledovaných barviv, charakter liposomních systémů a technologické postupy barvení chromočiněných usní. V průběhu experimentální práce mikroenkapslovaná barviva (kyselé a reaktivní) byla aplikována při barvení chromočiněných usní a byl sledován efekt mirkoenkapsulace na retardaci počáteční rychlosti barvení, vytažení barviva z lázně, hloubku probarvení, sytosti odstínu, egalizací vybarvení a celkový výpad vybarvení usní. Mikroenkapslovaná barviva vykazovala ve srovnání s původní nekapslovanou formou barviva vyšší hloubku probarvení, a světlejší odstín při jinak stejných vytahovacích charakteristikách a při zachování stejných hodnot stálostí vybarvení., The thesis deals with the microencapsulation of acid and reactive dyes into liposomic systems composed of lecithin and surfactant and application of this form in dyeing of chrome-tanned leather. In the theoretical section the basic theoretical and practical knowledge aimed at dyeing of chrome tanned leather are summarized. The next part is focused on study of microencapsulation technology, technique and conditions of capsule preparation, the possibility of phospholipid liposomes application in dyeing of protein substrates. In the experimental section are described the procedures for preparation of liposomic systems of monitored dyes, physico-chemical characteristics of liposomic systems and procedures used in dyeing of chrome-tanned leather. In the course of experimental works prepared microencapsulated dyes (acid and reactive dyes) were applied in dyeing of chrome-tanned leathers and the final effects of the microencapsulation were studied mainly in: retardation of the initial dyeing velocity, dyebath exhaustion, depth of shade, leveling of dyeing, saturation of color, color fastness properties, and through-dyeing of chrome-tanned leather. In comparison with the original dyestuffs forms, the microencapsulated dyes showed a brighter shade and a greater depth of through-dyeing at the same exhaustion characteristics and at the same color fastness values., Ústav chemie a technologie makromolekulárních látek

Les superfícies hidrofòbiques artificials són de gran interès en una àmplia gamma d’aplicacions industrials gràcies a les seves propietats d’autoneteja, anticontaminació biològica, antifongs, antiadherència i anticorrosió, entre d’altres. En la indústria tèxtil, són de gran interès materials amb propietats capaces de repel·lir l’aigua i compostos oliosos, ja que poden ser molt útils per a roba esportiva especial, tèxtils per a la llar com ara catifes o mobles entapissats, paraigües, etc. Seguint la trajectòria del nostre grup, hem sintetitzat colorants reactius amb diferents centres cromàtics que contenen a la seva estructura llargues cadenes polifluorades i grups funcionals que permeten el seu ancoratge sobre una superfície de cotó o vidre, de manera que hem obtingut nous materials hidrofòbics acolorits. Per tal d’estudiar la hidrofobicitat dels materials obtinguts, hem realitzat mesures de l’angle de contacte d’una gota d’aigua dipositada a la superfície de les teles tenyides i sobre vidres recoberts amb els nostres colorants sintetitzats. S’han obtingut angles més grans de 150º, en el cas dels teixits tenyits, la qual cosa demostra que són superhidrofòbics.Paraules clau: Colorant reactiu, fluor, cadenes polifluorades, hidrofobicitat., Artificial hydrophobic surfaces have a great potential in a wide range of industrial applications owing to their self-cleaning, anti-biofouling, anti-fogging, anti-sticking, anti-corrosion and anti-contamination properties. Equipment for fibers and textiles with hydrophobic properties is of high interest for fabrics with water, oil or soil repellent properties, e.g. for special sports clothes, home textiles like carpets or upholstered furniture, and some outdoor materials, such as umbrellas. Continuing along the line of research of our group, functional reactive dyes with different chromatic cores have been prepared with long polyfluorinated chains in their structure, and functional groups that allow their grafting on a cotton fabric surface or on glass, obtaining new colored hydrophobic materials. Contact angle measurements have been made of a droplet of water on the surface of stained fabrics and on glass coated with our new compounds. Angles higher than 150º have been obtained on the stained fabrics, proving that they are superhydrophobics.Keywords: Reactive dye, fluorine, polyfluorinated chains, hydrophobicity.

Two series of organobentonites (OBs) were synthesized from Na+-exchanged bentonite clay from Bogovina, Serbia. In the first series the starting material was modified using hexadecyltrimethylammonium (HDTMA(+)) ion in the amounts corresponding to 0.2, 0.5, 1.0 and 2.0 of the CEC value. The second series was obtained using quaternary alkyl ammonium cations (QAACs) with different alkyl chain lengths: hexadecyltrimethylammonium (HDTMA(+)), dodecyltrimethylammonium (DDTMA(+)) and tetramethylammonium (TMA(+)) ions. The synthesized OBs were characterized. The adsorption of anionic reactive dye Reactive Black 5 (RB5) and Pb2+ from single component solutions and their hi-component solution was investigated for both series of OBs. The adsorptive properties of the OBs were correlated to the amount and type of incorporated QAACs. The correlation was tested using different mathematical models and best fits were found. Experimental results showed that simultaneous adsorption of RB5 and Pb2+ exhibited synergic effect. The adsorption capacity for both RB5 and Pb2+ was higher in their hi-component solution than in single-component solutions. These results indicate the creation of new adsorption sites during the simultaneous adsorption.

Two series of organobentonites (OBs) were synthesized from Na+-exchanged bentonite clay from Bogovina, Serbia. In the first series the starting material was modified using hexadecyltrimethylammonium (HDTMA(+)) ion in the amounts corresponding to 0.2, 0.5, 1.0 and 2.0 of the CEC value. The second series was obtained using quaternary alkyl ammonium cations (QAACs) with different alkyl chain lengths: hexadecyltrimethylammonium (HDTMA(+)), dodecyltrimethylammonium (DDTMA(+)) and tetramethylammonium (TMA(+)) ions. The synthesized OBs were characterized. The adsorption of anionic reactive dye Reactive Black 5 (RB5) and Pb2+ from single component solutions and their hi-component solution was investigated for both series of OBs. The adsorptive properties of the OBs were correlated to the amount and type of incorporated QAACs. The correlation was tested using different mathematical models and best fits were found. Experimental results showed that simultaneous adsorption of RB5 and Pb2+ exhibited synergic effect. The adsorption capacity for both RB5 and Pb2+ was higher in their hi-component solution than in single-component solutions. These results indicate the creation of new adsorption sites during the simultaneous adsorption.

Two series of organobentonites (OBs) were synthesized from Na+-exchanged bentonite clay from Bogovina, Serbia. In the first series the starting material was modified using hexadecyltrimethylammonium (HDTMA(+)) ion in the amounts corresponding to 0.2, 0.5, 1.0 and 2.0 of the CEC value. The second series was obtained using quaternary alkyl ammonium cations (QAACs) with different alkyl chain lengths: hexadecyltrimethylammonium (HDTMA(+)), dodecyltrimethylammonium (DDTMA(+)) and tetramethylammonium (TMA(+)) ions. The synthesized OBs were characterized. The adsorption of anionic reactive dye Reactive Black 5 (RB5) and Pb2+ from single component solutions and their hi-component solution was investigated for both series of OBs. The adsorptive properties of the OBs were correlated to the amount and type of incorporated QAACs. The correlation was tested using different mathematical models and best fits were found. Experimental results showed that simultaneous adsorption of RB5 and Pb2+ exhibited synergic effect. The adsorption capacity for both RB5 and Pb2+ was higher in their hi-component solution than in single-component solutions. These results indicate the creation of new adsorption sites during the simultaneous adsorption.

Two series of organobentonites (OBs) were synthesized from Na+-exchanged bentonite clay from Bogovina, Serbia. In the first series the starting material was modified using hexadecyltrimethylammonium (HDTMA(+)) ion in the amounts corresponding to 0.2, 0.5, 1.0 and 2.0 of the CEC value. The second series was obtained using quaternary alkyl ammonium cations (QAACs) with different alkyl chain lengths: hexadecyltrimethylammonium (HDTMA(+)), dodecyltrimethylammonium (DDTMA(+)) and tetramethylammonium (TMA(+)) ions. The synthesized OBs were characterized. The adsorption of anionic reactive dye Reactive Black 5 (RB5) and Pb2+ from single component solutions and their hi-component solution was investigated for both series of OBs. The adsorptive properties of the OBs were correlated to the amount and type of incorporated QAACs. The correlation was tested using different mathematical models and best fits were found. Experimental results showed that simultaneous adsorption of RB5 and Pb2+ exhibited synergic effect. The adsorption capacity for both RB5 and Pb2+ was higher in their hi-component solution than in single-component solutions. These results indicate the creation of new adsorption sites during the simultaneous adsorption.

The effect of alkali and chitosan treatment on reactive dyeing characteristics of polyester/cotton blend is studied in this work. Various methods for characterization of physical and chemical changes in the surface layer of polyester fiber and dye utilization after individual and combine treatments were used. A simultaneous dyeing of cotton and polyester fabrics and dyeing of factory blends of polyester/cotton were carried out after individual and hybrid treatment. Dyed fabrics were evaluated by dye intensity and fastness. By using alkali treatment, the surface of polyester fiber is physically and chemically modified and at the same time the cotton is mercerized, favorably affecting absorption of reactive dye C.I. Reactive Red 3, resulting to a dye intensity increase of 24% on factory blend. With deposition of chitosan biopolymer, dye intensity on all samples is increased proportionally with concentration, especially on polyester. Hybrid treatment combining alkali and chitosan treatments is the most effective and it could enable a new approach to textile dyeing and finishing.

The effect of alkali and chitosan treatment on reactive dyeing characteristics of polyester/cotton blend is studied in this work. Various methods for characterization of physical and chemical changes in the surface layer of polyester fiber and dye utilization after individual and combine treatments were used. A simultaneous dyeing of cotton and polyester fabrics and dyeing of factory blends of polyester/cotton were carried out after individual and hybrid treatment. Dyed fabrics were evaluated by dye intensity and fastness. By using alkali treatment, the surface of polyester fiber is physically and chemically modified and at the same time the cotton is mercerized, favorably affecting absorption of reactive dye C.I. Reactive Red 3, resulting to a dye intensity increase of 24% on factory blend. With deposition of chitosan biopolymer, dye intensity on all samples is increased proportionally with concentration, especially on polyester. Hybrid treatment combining alkali and chitosan treatments is the most effective and it could enable a new approach to textile dyeing and finishing.

The adsorption of a reactive dye, Ariazol Scarlet 2G (AS2G) (C. I.: Reactive Red 234), onto compost, from aqueous solutions, was studied in a batch system. The effects of initial dye concentration, initial pH and sorbent mass have been studied. Four two-parameter isotherm models-Langmuir, Freundlich, Temkin and Harkins Jura - were used to fit the experimental data using a nonlinear trial-and-error method. The best fit of the adsorption isotherm data was obtained using the Langmuir model (X(2) = 1.97E-03). A comparison of kinetic models applied to the adsorption of AS2G on compost was evaluated using the pseudo-second order, Elovich and Lagergren first-order kinetic models. Results showed that the pseudo-second order kinetic model was found to agree well with the experimental data. An intra-particle diffusion model analysis showed multi-linearity with two steps and a non-zero intercept which indicated the intra-particle diffusion model is not a dominant rate controlling mechanism in the sorption of AS2G by compost.

The adsorption of a reactive dye, Ariazol Scarlet 2G (AS2G) (C. I.: Reactive Red 234), onto compost, from aqueous solutions, was studied in a batch system. The effects of initial dye concentration, initial pH and sorbent mass have been studied. Four two-parameter isotherm models-Langmuir, Freundlich, Temkin and Harkins Jura - were used to fit the experimental data using a nonlinear trial-and-error method. The best fit of the adsorption isotherm data was obtained using the Langmuir model (X(2) = 1.97E-03). A comparison of kinetic models applied to the adsorption of AS2G on compost was evaluated using the pseudo-second order, Elovich and Lagergren first-order kinetic models. Results showed that the pseudo-second order kinetic model was found to agree well with the experimental data. An intra-particle diffusion model analysis showed multi-linearity with two steps and a non-zero intercept which indicated the intra-particle diffusion model is not a dominant rate controlling mechanism in the sorption of AS2G by compost.

The electrochemical treatment of wastewaters from textile industry is a promising technique for substances which are resistant to biodegradation. This paper deals with the electrochemical decolourisation/degradation of synthetic solutions containing a reactive dye, C.I. Reactive Orange 4. Oxidation, reduction and oxido-reduction processes were evaluated using Ti/SnO 2-Sb-Pt and stainless steel electrodes as anode and cathode, respectively. Electrolyses were performed at galvanostatic conditions in a filter press reactor. Decolourisation and degradation were followed by means of total organic carbon (TOC), chemical oxygen demand (COD) measurements and high performance liquid chromatography (HPLC). A higher mineralisation rate for oxidation was found whilst oxido-reduction process gave more oxidised species. The kinetics of decolourisation was of pseudo-first order in all cases. The reduction process was the slowest process to decolourise. Gas chromatography-mass spectrometry (GC-MS) was employed to investigate the main intermediate compounds, confirming the presence of 2-amino-1, 5-naphthalenedisulphonic acid (2A15NDS) in solution. When this compound was generated, it was gradually degraded during the oxidation and oxido-reduction processes indicating the feasibility and durability of Ti/SnO 2-Sb-Pt electrodes. However, during the electrochemical reduction process, this compound was continuously generated but it was not degraded. © 2011 Elsevier B.V.

The adsorption of a reactive dye, Ariazol Scarlet 2G (AS2G) (C. I.: Reactive Red 234), onto compost, from aqueous solutions, was studied in a batch system. The effects of initial dye concentration, initial pH and sorbent mass have been studied. Four two-parameter isotherm models-Langmuir, Freundlich, Temkin and Harkins Jura - were used to fit the experimental data using a nonlinear trial-and-error method. The best fit of the adsorption isotherm data was obtained using the Langmuir model (X(2) = 1.97E-03). A comparison of kinetic models applied to the adsorption of AS2G on compost was evaluated using the pseudo-second order, Elovich and Lagergren first-order kinetic models. Results showed that the pseudo-second order kinetic model was found to agree well with the experimental data. An intra-particle diffusion model analysis showed multi-linearity with two steps and a non-zero intercept which indicated the intra-particle diffusion model is not a dominant rate controlling mechanism in the sorption of AS2G by compost.