Decolorization Of Textile Dyes Research Articles

Treatment of textile industry wastewater by electrocoagulation coupled with electrochemical advanced oxidation process

The present study deals with the treatment of real effluents, containing a mixture of reactive dyes (mainly methylene blue), by electrocoagulation (EC) coupled with electrochemical advanced oxidation processes (EAOPs) such as peroxi-coagulation (PC), anodic oxidation (AO), and electro-Fenton (EF), individually. To choose the right treatment process, the key criteria should be higher degradation efficiency and minimal energy consumption. Textile effluents are physico-chemical characterized and the operating parameters i.e. the initial pH, the current density, and the electrolysis time, were investigated. Wastewater treatment energy consumption was evaluated for each combined process. The results highlighted high efficiency of electrochemical processes in effective degradation of organic pollutants at the optimum operating conditions. Among the electrochemical advanced oxidation processes tested, sequential EC-EF treatment was being preferred and quite effective since it provided electro generated hydroxyl radical OH especially when using the boron-doped diamond. Thus, removals of 97%, 100% and 100% for, respectively, TOC, turbidity and color removal were achieved by using the EC-EF combined process. Energy consumption values were evaluated for textile dye decolorization as 0.45–1.5 kW h kg−1 of the removed TOC, depending on the applied current density. Regarding the efficiency level and the operating cost, the EC-EF combined process offers many advantages allowing the reuse of the treated water for other purposes.

Comparison of indigo carmine decolorization by Pseudomonas aeruginosa and crude laccase enzyme from Funalia trogii.

The effects of incubation time, temperature, initial pH, and dye concentration on the indigo carmine decolorization activity of Pseudomonas aeruginosa ATCC 10145 and some factors on the decolorization potential of crude laccase enzyme obtained from Funalia trogii ATCC 200800 were comparatively investigated. This bacterium showed effective decolorization activity at all agitation and temperature values. Indigo carmine was greatly decolorized by P. aeruginosa at all pH values except pH 10. A decrease in decolorization activity occurred with increasing dye concentration, but this bacterium effectively decolorized the dye within 24 h. The decolorization process was through microbial metabolism, not biosorption. No decolorization or laccase activity could be obtained by the cell-free intracellular extract or culture filtrate of this bacterium. On the other hand, crude laccase effectively decolorized indigo carmine under highly acidic conditions, especially at pH 3.0 as 57% in 300 seconds. This activity decreased progressively due to the increase in pH values. In a short incubation period and at high temperature values, the crude laccase enzyme removed the color of the dye at 50 °C (56%), 60 °C (45%), and 70 °C (38%). These data are important for improving methods for decolorization of textile dyes used at high temperatures in various industrial applications.

Textile azo dye decolorization and detoxification using bacteria isolated from textile effluents

Textile azo dye decolorization and detoxification using bacteria isolated from textile effluents

Combined biological and advanced oxidation process for decolorization of textile dyes

The present study evaluated the efficiency of combined biological and AOPs treatment (Bio–AOP) using Aeromonas hydrophila SK16 and AOPs-H2O2 (4%) for the remediation of the textile dyes. Bio–AOP treatment showed 100% decolorization of Reactive Red 180 (RR 180), Reactive Black 5 (RB 5) and Remazol Red (RR), while 72% decolorization was observed in individual treatments. Combined treatment significantly reduced BOD and COD of RR 180–78 and 68%, RB 5–52 and 83% and RR—42 and 47%, respectively as compare to individual treatment. Significant increased levels of tyrosinase, laccase, lignin peroxidase, riboflavin reductase and azoreductase were observed in A. hydrophila SK16. Fourier-transform infrared spectroscopy and high-performance liquid chromatography analysis showed noteworthy biotransformation of textile dyes. Possible metabolic pathway of degradation of dyes were predicted based on GC–MS analysis. This study indicates that the Bio–AOP treatment is more efficient than an individual treatment of textile wastewater.

Potential use of bacteria collected from human hands for textile dye decolorization

We obtained dye-decolorizing bacteria from the hands of ordinary people with an efficiency of approximately 40%. The bacteria were classified into the azo dye-decolorizing group and anthraquinone dye-decolorizing group. The former were capable of decolorizing real textile wastewater, whereas the latter could achieve only partial decolorization. These bacterial strains can potentially be applied to assess the major types of dyes in textile wastewater and dye-polluted rivers. The azo dye-decolorizing bacterial strain degraded Congo red into its intermediates and then further degraded phenyl compounds. Interestingly, the azo dye-decolorizing bacterial strain produced a significant amount of protein (20–60 mg L−1), which correlated with the dye-decolorization rate. We further identified cell density as the main factor affecting stabilization of the dye-decolorization reaction. In summary, human hands are a readily accessible source from which to collect dye-decolorizing bacteria that can be used to treat textile wastewater and to remediate environmental pollution sites.

Covalent immobilization of laccase by one pot three component reaction and its application in the decolorization of textile dyes

In present study, laccase from Myceliophthora thermophila, was immobilized on epoxy-functionalized silica via one-pot three component reaction as a novel and efficient method for immobilization. The results revealed immobilization of 50 mg of M. thermophila laccase on 1 g of the supports in presence of cyclohexyl isocyanide after 12 h of incubation. The immobilized enzyme exhibited notable activity (50 U/g) with improved stability toward pH, temperature and organic solvents. Laccase derivative was used for decolorization of five textile dyes (acid orange 156, acid red 52, coomassie brilliant blue, methyl violet, malachite green) with or without the redox mediators such as 1-hydroxybenzotriazole (HBT), catechol, syringaldehyde and N-hydroxyphthalimide (HPT). The results showed that laccase/mediator systems were effective biocatalysts for the treatment of textile dyes.

Toxicity of enzymatically decolored textile dyes solution by horseradish peroxidase.

The oxidative systems including enzymatic systems have been widely studied as an alternative for textile effluents treatment. However, studies have shown that some oxidative processes can produce degradation products with higher toxicity than the untreated dye. In this work, enzymatic dye decolorization was evaluated by horseradish peroxidase enzyme (HRP) and the toxicity of discoloration products was evaluate against Daphnia magna, Euglena gracilis algae, and Vibrio fischeri. Dye decolorization kinetics data were evaluated and the pseudo-second-order model showed the best-fitting to the experimental data. In addition, it was observed an increased acute and chronic toxicity associated with the decolorization efficiency. The Reactive Blue 19 and Reactive Black dye showed the highest toxicity against D. Magna (16 toxicity factor) and V. Fischeri (32 toxicity factor) after enzymatic decolorization. For the chronic toxicity against D. Magna, Reactive Red was the only dye with no fertility inhibition. In relation to toxicity tests with E. gracilis algae, it was not observed photosynthetic inhibition for all dyes. This study verified the viability of the enzyme horseradish peroxidase in the textile dyes decolorization and the importance to evaluate the decolorization products.

In situ phytoremediation of dyes from textile wastewater using garden ornamental plants, effect on soil quality and plant growth

In situ phytoremediation of dyes from textile wastewater was carried out in a high rate transpiration system ridges (91.4 m × 1.0 m) cultivated independently with Tagetes patula, Aster amellus, Portulaca grandiflora and Gaillardia grandiflora which reduced American Dye Manufacturers Institute color value by 59, 50, 46 and 73%, respectively within 30 d compared to dye accumulated in unplanted ridges. Significant increase in microbial count and electric conductivity of soil was observed during phytoremediation. Reduction in the contents of macro (N, P, K and C), micro (B, Cu, Fe and Mn) elements and heavy metals (Cd, As, Pb and Cr) was observed in the soil from planted ridges due to phyto-treatment. Root tissues of these plants showed significant increase in the specific activities of oxido-reductive enzymes such as lignin peroxidase, laccase, veratryl alcohol oxidase, tyrosinase and azo reductase during decolorization of textile dyes from soil. Anatomical studies of plants roots revealed the occurrence of textile dyes in tissues and subsequent degradation. A minor decrease in plant growth was also observed. Overall surveillance suggests that the use of garden ornamental plants on the ridges of constructed wetland for the treatment of dyes from wastewater along with the consortia of soil microbial flora is a wise and aesthetically pleasant strategy.

Decolorization and detoxification of textile dyes using a versatile Streptomyces laccase-natural mediator system.

Currently, there is increasing interest in assessing the potential of bacterial laccases for industrial and environmental applications especially in harsh conditions. The environmental impact of the textile industry requires novel and effective technologies to mitigate the presence of dyes in wastewaters before discharging into the environment. Dyes usually remain stable in the presence of a variety of chemicals, light and are recalcitrant to microbial degradation. Among available technologies the biological treatments offer environmentally friendly strategies for decolorizing and detoxifying these compounds. The recent discovery of versatile laccases in streptomycetes opens up new opportunities for their commercial application. The aim of this study is to assess the potential of a novel bacterial laccase SilA produced by Streptomyces ipomoeae CECT 3341 active over wide temperature and pH ranges for use as an eco-friendly, biological treatment for the degradation of textile dyes. Insights into the enhancement of the oxidative action of this enzyme through the use of natural redox mediators are presented together with an assessment of the potential toxicity of the degradation products. Our results confirm that the combination of the laccase and natural mediators such as acetosyringone and methyl syringate enhanced the decolorization and detoxification of a variety of textile dyes up to sixfold and 20-fold, respectively. Mediator concentration was found to have a significant effect (p < 0.05) on dye decolorization at 60 °C; thus, the decolorization of Acid Orange 63 increased from 6 to 70-fold when the mediator concentration was increased from 0.1 to 0.5 mM. Further, the toxicity of tartrazine decreased 36-fold when the SilA-MeS system was used to decolorize the dye. The thermal properties of the SilA coupled with the stability of SilA at high pH suggest a potential commercial application for use in the decolorization of textile wastewaters which generally are performed at high temperature (>55 °C) and salinity and neutral pH, conditions which are unfavourable for conventional fungal laccases.

R software package based statistical optimization of process components to simultaneously enhance the bacterial growth, laccase production and textile dye decolorization with cytotoxicity study.

The thermophilic bacterium, Bacillus licheniformis U1 is used for the optimization of bacterial growth (R1), laccase production (R2) and synthetic disperse blue DBR textile dye decolorization (R3) in the present study. Preliminary optimization has been performed by one variable at time (OVAT) approach using four media components viz., dye concentration, copper sulphate concentration, pH, and inoculum size. Based on OVAT result further statistical optimization of R1, R2 and R3 performed by Box–Behnken design (BBD) using response surface methodology (RSM) in R software with R Commander package. The total 29 experimental runs conducted in the experimental design study towards the construction of a quadratic model. The model indicated that dye concentration 110 ppm, copper sulphate 0.2 mM, pH 7.5 and inoculum size 6% v/v were found to be optimum to maximize the laccase production and bacterial growth. Whereas, maximum dye decolorization achieved in media containing dye concentration 110 ppm, copper sulphate 0.6 mM, pH 6 and inoculum size 6% v/v. R package predicted R2 of R1, R2 and R3 were 0.9917, 0.9831 and 0.9703 respectively; likened to Design-Expert (Stat-Ease) (DOE) predicted R2 of R1, R2, and R3 were 0.9893, 0.9822 and 0.8442 respectively. The values obtained by R software were more precise, reliable and reproducible, compared to the DOE model. The laccase production was 1.80 fold increased, and 2.24 fold enhancement in dye decolorization was achieved using optimized medium than initial experiments. Moreover, the laccase-treated sample demonstrated the less cytotoxic effect on L132 and MCF-7 cell lines compared to untreated sample using MTT assay. Higher cell viability and lower cytotoxicity observed in a laccase-treated sample suggest the impending application of bacterial laccase in the reduction of toxicity of dye to design rapid biodegradation process.

Comparative study on crude and partially purified laccase from Polyporus durus ATCC 26726 in the decolorization of textile dyes and wastewater treatment

Background and objective In textile processing, 50% of the dye is released as effluent which is considered as hazardous contaminant that threats environment and human life. The use of laccase enzyme for dye decolorization is cost effective and environmentally friendly. So, the main objective of the present study is the production of microbial laccase with high yield using low-cost substrates. The study also involved comparing and evaluating the dye decolorization efficiency of both crude and partially purified laccase enzymes. Materials and methods Six fungal strains were tested for laccase productivity. Some agro-industrial wastes were evaluated for laccase production by the most potent fungus. The produced laccase was partially purified by acetone precipitation. Both the crude and the partially purified laccase were evaluated for decolorization of some textile dyes and two synthetic wastewater solutions. Results and conclusion The fungus Polyporus durus ATCC 26726 exhibited the highest laccase productivity among all the tested fungi. Maximal enzyme productivity (2297 U/ml) was reached after 7 days by submerged fermentation using a medium containing 60 g/l wheat bran with the addition of 1 mmol/l copper on the fifth day of fermentation. The produced laccase was partially purified by 40% acetone concentration with an 8.1-fold purification factor. Both the crude and the partially purified laccase exhibited high efficiency to decolorize reactive blue 19, acid blue 225, and reactive violet 5 dyes. The crude enzyme exhibited 100 and 96.4% decolorization activities against the synthetic wastewater solutions A and B, respectively. However, the decolorization activity of the partially purified enzyme was 100% against both solutions A and B. Hence laccase enzyme from P. durus ATCC 26726 could be used effectively for the removal of textile dye pollutants in both its crude and partially purified form without the need to redox mediators.

Decolorization of textile dyes by combination of gold nanocatalysts obtained from Acinetobacter sp. SW30 andNaBH4

Abstract In the present work, a new strategy for decolorization of textile dyes such as direct black 22 (DB) and reactive yellow 186 (RY) has been studied using sodium borohydride 100 mM ( NaBH 4 ) as a reducing agent and 6 . 5 μ g ∕ ml bacteriogenic gold nanoparticles (AuNP) as nanocatalysts. The combination of two could decolorize 93 and 83% of DB and RY in 20 and 30 min respectively. The rate constant for both the dyes were very less, indicating the higher affinity of AuNP for dyes. FTIR, HPLC and GC–MS confirm that NaBH4 reduces the dye at azo bond leading to decolorization of dyes. Phytotoxic and cytotoxic studies were performed on bulbs of Allium cepa which revealed the non-toxic nature of degraded metabolites towards onion bulbs. AuNP can be immobilized in sodium alginate beads and can be reused for 3 times with same efficiency of decolorization. This is the first report on the decolorization of textile azo dyes using AuNP as catalysts.

Bacterial laccase: recent update on production, properties and industrial applications.

Laccases (benzenediol: oxygen oxidoreductase, EC 1.10.3.2) are multi-copper enzymes which catalyze the oxidation of a wide range of phenolic and non-phenolic aromatic compounds in the presence or absence of a mediator. Till date, laccases have mostly been isolated from fungi and plants, whereas laccase from bacteria has not been well studied. Bacterial laccases have several unique properties that are not characteristics of fungal laccases such as stability at high temperature and high pH. Bacteria produce these enzymes either extracellularly or intracellularly and their activity is in a wide range of temperature and pH. It has application in pulp biobleaching, bioremediation, textile dye decolorization, pollutant degradation, biosensors, etc. Hence, comprehensive information including sources, production conditions, characterization, cloning and biotechnological applications is needed for the effective understanding and application of these enzymes at the industrial level. The present review provides exhaustive information of bacterial laccases reported till date.

In Silico Analysis of Bacterial Systems For Textile Azo Dye Decolorization and Affirmation With Wetlab Studies

A systemic approach involving in‐silico and in‐vitro tests were used for the decolorization of five azo dyes, Reactive Yellow F3R, Joyfix Yellow 53R, Remazol Red RR, Drimaren Black CL‐S and Disperse Red F3BS, using Aeromonas hydrophila SK16 and Lysinibacillus sphaericus SK13. Homology models for laccase and azoreductase enzymes from these two bacteria were generated using Accelrys Discovery Studio 3.5 and validated. Docking was performed with LeadIT software for binding energy calculation, and active site residues were identified. Reactive Yellow F3R showed highest binding energy with A. hydrophila, which emulated the decolorization percentage by ultraviolet–visible (UV–vis) spectroscopy. High‐performance LC (HPLC), Fourier transform IR spectroscopy (FTIR), and gas chromatography–mass spectrometry (GCMS) supported biotransformation and biodegradation of Reactive Yellow F3R by A. hydrophila SK16, and a biodegradation pathway was proposed. HPLC analysis of treated sample illustrated peaks at retention time 1.481, 3.165, 3.374, and 3.945 min while the control dye showed peaks at 1.478 and 3.106 min. GCMS analysis showed that (2Z)‐but‐2‐ene, 1,3,5‐triazine, aniline, and naphthalene were formed as end products. The in‐silico outcome was in good agreement with experimental studies. Thus, it can be surmised that in‐silico molecular modeling and docking studies can assist as a preliminary tool for screening of potential bacterial system to be employed in textile dye decolorization and degradation studies.

Decolorization of Textile Dye- Malachite Green

Decolorization of Textile Dye- Malachite Green

Optimization of conditions for decolorization of azo-based textile dyes by multiple fungal species

Wastewater from textile industries contains azo dye residues that negatively affect most environmental systems. The biological treatment of these wastes is the best option due to safety and cost concerns. Here we isolated and identified 19 azo dye-degrading fungi and optimized conditions resulting in enhanced degradation. The fungi belonged to five species of Aspergillus and a single Lichtheimia sp. All fungi were evaluated for their ability to decolorize 20 azo dyes. While the most easily transformable azo dye was direct violet (decolorization ranged from 71.1 to 93.3%), the most resistant to decolorization was fast green azo dye. The greatest degradation potential of azo dyes (direct violet and methyl red) was optimized using the most promising four fungal strains and changing media glucose concentration, nitrogen source, and micronutrients. Biomass, lignin peroxidase, and laccases production were also determined in the optimization studies. The decolorization of both azo dyes by the four fungal strains was greatly enhanced by glucose supplementation. The fungal strains were not able to produce lignin peroxidases in the absence of organic nitrogen source. Both yeast extract and casamino acid supplementation enhanced decolorization of direct violet and methyl red dyes and production of lignin peroxidase by the fungal strains. In contrast, the laccases were absent in the similar medium enriched with the same organic nitrogen sources.

Decolorization of textile dyes in an air-lift bioreactor inoculated with Bjerkandera adusta OBR105

ABSTRACTA new decolorizing white-rot fungus, OBR105, was isolated from Mount Odae in South Korea and identified by the morphological characterization of its fruit body and spores and partial 18s rDNA sequences. The ligninolytic enzyme activity of OBR105 was studied to characterize their decolorizing mechanism using a spectrophotometric enzyme assay. For the evaluation of the decolorization capacity of OBR105, the isolate was incubated in an erlenmeyer flask and in an airlifte bioreator with potato dextrose broth (PDB) medium supplemented with each dye. In addition, the decolorization efficiency of real textile wastewater was evaluated in an airlift bioreactor inoculated with the isolate. The isolate was identified as Bjerkandera adusta and had ligninolytic enzymes such as laccase, lignin peroxidase (LiP), and Mn-dependent peroxidase (MnP). Its LiP activity was higher than its MnP and laccase activities. B. adusta OBR105 successfully decolorized reactive dyes (red 120, blue 4, orange 16, and black 5) and acid dyes (red 114, blue 62, orange 7, and black 172). B. adusta OBR105 decolorized 91–99% of 200 mg L−1 of each dye (except acid orange 7) within 3 days in a PDB medium at 28°C, pH 5, and 150 rpm. This fungus decolorized only 45% of 200 mg L−1 acid orange 7 (single azo-type dye) within 3 days, and the decolorization efficiency did not increase by prolonging the cultivation time. In the air-lift bioreactor, B. adusta OBR105 displayed a high decolorization capacity, greater than 90%, for 3 acid dyes (red 114, blue 62, and black 172) and 1 reactive dye (blue 4) within 10–15 h of treatment. B. adusta OBR105 could decolorize real textile wastewater in the air-lift bioreactor. This result suggests that an air-lift reactor employing B. adusta OBR105 is a promising bioreactor for the treatment of dye wastewater.

Photocatalytic potential of ZnO/TiO2: a bionanocomposite from Ocimum basilicum

Decolorization of textile dyes by photocatalysis is an area that has gained considerable interest due to the need to minimize pollution. Nanocomposites possess prominence owing to their small size, good catalytic activity, high surface area and selectivity. Although nanocomposites have been synthesized by conventional techniques, green synthesis remains an unexplored area. Thus, the present study is the first one on ‘green’ synthesis of a zinc oxide (ZnO)/titanium dioxide (TiO2) nanocomposite using leaf extract of Ocimum basilicum L. var. purpurascens Benth. Lamiaceae as a novel source, along with an insight into its photocatalytic potential for decolorization of the textile dye Blue RGB under sunlight and ultraviolet (UV) irradiation. Hexagonal-shaped zinc oxide/titanium dioxide nanocomposites with a size of 50 nm have been synthesized and characterized using X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and energy-dispersive X-ray spectroscopy. Maximum photodecolorization was observed for sunlight-mediated photocatalytic decolorization (99·8%) compared to UV (95·8%) within 8 h. The study adds value to the applications of nanoparticles in various fields such as photocatalysis for degradation of pollutants and in wastewater treatment.

Decolorization of Textile Dyes in Two Different Medium

Bu calismada tekstil fabrikasindan alinan uc farkli tekstil boyasinin (Doracryl Blue (DB), Astrozon Red (AR) and Maxillon Red (MR)) atik sudan izole edilen bakteriyel kultur ile renk giderimi tespit edilmistir. Biyoakumulasyon orani, iki farkli besiyerinde (Nutrient Broth ve Melasli Besiyeri) baslangic pH (5-8), boya konsantrasyonu (100-500 mgL -1 ) ve sicakliga (25-35oC) karsilik tespit edilmistir. Her iki besiyerinde de inkubasyon periyodu boyunca pH 7 ve 8’de yuksek oranlarda giderim tespit edilmistir. Bakteriyel kultur MR ve DB boyalarini tum yuksek konsantrasyonlar ve sicakliklarda %95 oraninda gidermistir. Bunun yaninda AR ise 200 mgL -1 konsantrasyonda %40 oraninda giderilmis ve daha yuksek konsantrasyonlarda giderilememistir. Calismada elde edilen sonuclar bakteriyel kulturun MR ve DB boyalarini tum konsantrasyon ve sicakliklarda yuksek oranda gidermesine karsin AR’nin yuksek oranda dekolorize edilmedigini ortaya koymustur. Bundan dolayi bakteriyel kultur DB ve MR boyalarinin dekolorizasyonu icin kullanilabilecekken AR icin sinirli kullanim alanina sahiptir

Electrochemical Decolorization of Reactive Violet 5 Textile Dye using Pt/Ir Electrodes

Electrochemical decolorization of textile dyeing wastewater containing Reactive Violet 5 (RV5) were investigated at Pt/Ir electrodes in the presence of 75%NaCl+25%Na 2 CO 3 (w/w) supporting electrolyte mixture in a batch electrochemical reactor. Experimental parameters were operated in the range of 300-1500 mg/L textile dye concentration, 4-20 g/L 75%NaCl+25%Na 2 CO 3 electrolyte concentration, 5-15 mA/cm 2 current density, and 20-60°C reaction temperature in 15 min electrolysis time. Reactive Violet 5 decolorization increased with increasing current density and electrolyte concentration, and decreasing the textile dye concentration. Although a slight increase obtained in color removal efficiency, the temperature was not show much significant effect on decolorization. Depending on electrochemical reaction conditions, Reactive Violet 5 textile dye decolorization were obtained between 42.8-100%.