Decolorization Of Textile Wastewater Research Articles

Electrocoagulation for the decolorization of textile wastewater in single-channel reactor: Response surface methodology for optimization and a novel model exploitation

This work focuses on the multi-objective optimization of the electrocoagulation process. The goal is to decolorize synthetic Reactive Black 5 wastewater using a single-channel reactor operating in a closed-circuit. Response Surface Methodology (RSM) is employed for the optimization. The Central Composite Design (CCD) is used to study the empirical relationship between two responses (decolorization efficiency (η) and energy consumption (WC)) and four independent variables (recirculation flow rate (Qv), current intensity (I), electrolysis time (τe) and active electrode area (Sa)), while the desirability function (D) is applied to determine optimal conditions. In addition, a novel approach for the exploitation of the RSM model is developed to set correlations between the limit of η (ηLim) and corresponding independent variables’ limit values (below of which η < ηLim). The developed correlations showed a good agreement between the graphical data and the estimated values (R2 > 0.99). The CCD model fits well the experimental data with a R2 of 0.94 and 0.95, for η and WC, respectively. The analysis of variance allowed to build quadratic models for both responses. For a maximal overall desirability D of 0.88, optimal conditions are Qv = 70 L h−1, I = 100 mA, τe = 34.6 min and Sa = 621 cm2. Under these conditions, η = 70.9% and WC = 4.6 Wh.m−3 were achieved. The sludge characterization using X-ray diffraction, Scanning Electron Microscopy, and Fourier Transform InfraRed reveals the formation of the amorphous Al(OH)3 without other precipitated substances and authenticates the successful sorption of RB5 onto the Aluminum hydroxide flocs.

Efficient photocatalytic decolorization of textile wastewater using Fe-Mo LDH/ZnO nanocomposite: A sustainable approach for environmental remediation

The efficient treatment of dye-contaminated wastewater using environmentally friendly technologies holds considerable significance. This study delves into the synthesis of Iron-Molybdenum Layered Double Hydroxide/Zinc Oxide (Fe-Mo LDH/ZnO) nanocomposite using a hydrothermal technique and evaluating its performance in adsorption and photocatalysis for decolorizing textile wastewater under ultraviolet (UV) irradiation. The synthesized photocatalyst was characterized through various analytical techniques, including Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), Energy dispersive X-ray spectroscopy (EDX), Elemental mapping, Vibrating sample magnetometer (VSM), Diffuse reflectance spectroscopy (DRS), Brunauer-Emmett-Teller (BET), Photoluminescence spectroscopy, and Transient photocurrent density analyses. Additionally, the study investigated the impact of different parameters such as pH, contact time, photocatalyst amount, and oxidant amount on dye removal efficiency using central composite design (CCD) experiments. Optimal conditions resulted in an impressive 97.50 % dye removal efficiency, achieved with 0.75 g/L of Fe-Mo LDH/ZnO, 0.095 M of sodium persulfate as the oxidizing agent, 156 min of contact time, and adjustment the pH of the wastewater to 3.1. The dye removal process followed pseudo-first-order kinetics, with a maximum adsorption capacity at 25 °C of 28.33 mg/g. Moreover, the photocatalyst maintained its efficiency over 5 cycles, showing no significant reduction in dye removal efficiency, which indicates its reusability and cost-effectiveness for practical applications. This research demonstrates the desirable potential of Fe-Mo LDH/ZnO nanocomposite as a highly efficient and environmentally friendly photocatalytic adsorbent for the treatment of dye wastewater, providing valuable insights for sustainable water resource management and pollution control strategies.

Unveiling antibacterial and antioxidant activities of zinc phosphate-based nanosheets synthesized by Aspergillus fumigatus and its application in sustainable decolorization of textile wastewater

BackgroundThe development of an environment-friendly nanomaterial with promising antimicrobial and antioxidant properties is highly desirable. The decolorization potentiality of toxic dyes using nanoparticles is a progressively serious worldwide issue.MethodsThe successful biosynthesis of zinc nanoparticles based on phosphates (ZnP-nps) was performed using the extracellular secretions of Aspergillus fumigatus. The antibacterial activity of the biosynthetic ZnP-nps was investigated against Gram-negative bacteria and Gram-positive bacteria using the agar diffusion assay method. The antioxidant property for the biosynthetic nanomaterial was evaluated by DPPH and H2O2 radical scavenging assay.ResultsRemarkable antibacterial and antiradical scavenging activities of ZnP-nps were observed in a dose-dependent manner. The minimum inhibitory concentration (MIC) for Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli was 25 µg/ml, however, the MIC for Bacillus subtilis was 12.5 µg/ml. The maximum adsorptive performance of nanomaterial was respectively achieved at initial dye concentration of 200 mg/L and 150 mg/L using methylene blue (MB) and methyl orange (MO), where sorbent dosages were 0.5 g for MB and 0.75 g for MB; pH was 8.0 for MB and 4.0 for MO; temperature was 30 °C; contact time was 120 min. The experimental data was better obeyed with Langmuir’s isotherm and pseudo-second-order kinetic model (R2 > 0.999). The maximum adsorption capacity (qmax) of MB and MO dyes on nanomaterial were 178.25 mg/g and 50.10 mg/g, respectively. The regenerated nanomaterial, respectively, persist > 90% and 60% for MB and MO after 6 successive cycles. The adsorption capacity of the prepared zinc phosphate nanosheets crystal toward MB and MO, in the present study, was comparable/superior with other previously engineered adsorbents.ConclusionsBased on the above results, the biosynthesized ZnP-nanosheets are promising nanomaterial for their application in sustainable dye decolorization processes and they can be employed in controlling different pathogenic bacteria with a potential application as antiradical scavenging agent. Up to our knowledge, this is probably the first study conducted on the green synthesis of ZnP-nanosheets by filamentous fungus and its significant in sustainable dye decolorization.

Physicochemical Modifications and Decolorization of Textile Wastewater by Ozonation: Performance Evaluation of a Batch System

ABSTRACT This is an experimental study on the decolorization efficiency and the degradation of organic compounds from textile wastewater by the ozonation process in a batch system. The effects of different sample volumes of textile wastewater over time were investigated. The experiments were performed in a 1 L glass reactor with a magnetic stirrer and a bubble diffuser at the bottom to feed the ozone. The applied cumulative ozone dosage varied at 120 gO3 L−1, 60 gO3 L−1, and 30 gO3 L−1, and the total interaction time for each test was 1 h. To investigate the physicochemical properties of the textile wastewater (solid and liquid phases) before and after the treatment, multiple analytical characterization methods were used: Thermal Gravimetric Analysis, Scanning Electron Microscopy coupled with Energy-Dispersive X-ray Spectroscopy, X-ray diffraction, Fourier Transform Infrared spectroscopy, and Spectrophotometer. The most perceptive change was observed in the color of the liquid medium, which turned from black to transparent, and a visual color number indicator known as DurchsichtFarbZahl (DFZ) was used for the evaluation of this process. Absorbance values decreased about 3.5 times after 5 min of treatment with a 0.15 L sample volume, and these values differed for tests with larger sample volumes. FTIR spectroscopy demonstrated that the bands’ intensities associated with the C − H, C − N, and C − O decrease during treatment. On the other hand, it was possible to conclude that combining treatment methods to improve the degradation of persistent compounds after the ozonation process is necessary. Finally, the ozonation of the textile wastewater proved to be effective at removing color due to its high reaction capacity.

Textile Wastewater Decolorization by Pleurotus ostreatus in Organic Material Board Media

The textile industry in one of the fastest industries that grow today. However, the increased activity makes the production of liquid wastewater also increased because the use of water reaches 80% in production. The wastewater can endanger the aquatic ecosystems because it contains toxic dyes. Pleurotus ostreatus has ligninolytic enzymes that are capable of degrading synthetic dyes into non-toxic forms to the environment. This study aims to determine the optimum contact time of P. ostreatus in organic material board media for the best result in textile wastewater decolorization. This research used an experimental method. The research consisted preparation of P. ostreatus isolate, making of seed media, inoculation into seed media, making of log media, inoculation into log media, making of board media, and decolorization process. The parameters tested were different contact time (24, 48, 72, 96, 120, 144, and 168 hours), Total Dissolved Solid (TDS), pH, and temperature. The result of this research was that the treatment of P. ostreatus in organic material board media can decolorize textile wastewater. The value of highest decolorization percentage was 35,69% at 24 hours contact time. There are change of TDS, pH, and temperature on before and after namely 835 to 566, 8.7 to 7.62, 28.3 to 31. This board system is promising for wastewater treatment.Keywords:decolorization, textile wastewater, P. ostreatus, board media

Probing the performance and mechanisms of Congo red wastewater decolorization with nanoscale zero-valent iron in the continuing flow reactor

Rapid and efficient decolorization is great challenging for wastewater treatment, and nanoscale zero-valent iron (nZVI) was recognized as an environmental-friendly and economical-cost agent for effective decolorization of textile wastewater. Herein, the performance and mechanisms of Congo Red (CR) wastewater treatment with nZVI were probed in a continuous flow nano-iron reactor (NIR), which included the “reaction, separation and reuse” process. CR wastewater (initial concentration up to 500 mg·L−1) was successfully decolorized by nZVI in the NIR during the 125 d continuous running period. The color removal efficiency achieved 98.59%, accompanied with a large removal capacity of 6.64 mg-CR/g-nZVI at an average low nZVI dose (0.075 g-nZVI/L-CR). The decolorization mechanism of CR wastewater was ascribed to the chromophore groups (–N=N–) breaking, the final productive products were 4-Amino-1-naphthalene sulfonic acid and 4,4′-diaminodiphenyl, which were proved by liquid chromatography coupled to mass spectrometry, X-ray photoelectron spectroscopy, UV–Vis spectrophotometer, infrared spectroscopy. Decolorization efficiencies were up to 77.82% and 87.95% on average for two actual textile wastewater in the NIR, during the 83.5 h and 445 h continuous running period. This work provides proof that the nZVI technology can offer tremendous potential for the decolorization of recalcitrant organic dye wastewater.

Optimization studies on decolorization of textile wastewater using natural coagulants

The textile industry produces large amounts of wastewater from various finishing and dyeing processes. The eco-friendly coagulants which are readily available and low-cost, can be chosen as an alternative to other conventional coagulation methods. A study on the removal of commercially used dye from textile wastewater was conducted to investigate the effectiveness of coagulation with natural coagulants. Natural coagulants can treat low to high turbid water and have remarkable color removal efficiency that can be used for various purposes. Four types of Natural coagulants, viz Maize, Green beans, Nirmal seeds (Strychnos potatorum), and Moringa seeds, were studied. Moringa seeds were the promising coagulant for color removal from textile wastewater. Further, the process parameters like coagulant concentration, pH, and mixing time to decolorize textile wastewater were optimized using Response surface methodology (RSM). The optimum conditions from RSM for the maximum decolorization were obtained at coagulant concentration 55 mg/L, pH 6.5, and mixing time 62.5 min. At these optimum conditions, maximum decolorization obtained 98.7%, TDS-312 ppm & Turbidity-3 NTU. The decolorization of the textile wastewater using natural coagulants was best described by a second-order polynomial equation with a correlation coefficient R2 of 0.9868.

Decolorization of textile wastewater by electrooxidation process using different anode materials: Statistical optimization.

The presence of reactive dyes in textile wastewater is a serious environmental concern due to their associated mutagenic and carcinogenic effects. The present study aims to analyze the effect of different anodic materials on the decolorization of a real textile wastewater effluent. For this purpose, four different anodic materials-TiO2 -coated platine, TiO2 -coated ruthenium dioxide (RuO2 ) (viz., RuO2 ), titanium dioxide (TiO2 ), and graphite-were connected, respectively, to titanium dioxide (TiO2 ) used as a cathode electrode. Color and cost optimization studies were performed using the response surface methodology and the Box-Behnken experimental design (BBD). According to ANOVA results, the R2 values for Pt/TiO2 , RuO2 /TiO2 , TiO2 /TiO2 , and graphite/TiO2 electrode pairs were found to be 97.4%, 93.8%, 92.44%, and 92.2%, respectively, indicating a good compatibility as it is close to one. The results show that color removal efficiencies at the optimal conditions were 86.3%, 90.8%, 91.5%, and 93.6% for Pt/TiO2 , graphite/TiO2 , TiO2 /TiO2 , and RuO2 /TiO2 , respectively. Furthermore, energy consumption cost at the optimum conditions was also evaluated, and the results were as follows: Pt/TiO2 (0.95 €/m3 ), graphite/TiO2 (0.74 €/m3 ), TiO2 /TiO2 (0.31 €/m3 ), and RuO2 /TiO2 (0.26 €/m3 ). Consequently, this research paper shows that all of the tested anodic materials give satisfactory color removal efficiencies higher than 86%. When energy consumption and color removal are considered together, the use of TiO2 /TiO2 and RuO2 /TiO2 pairs would be preferred. PRACTITIONER POINTS: Anodic contribution was investigated for decolorization of textile wastewater by electrooxidation process. Graphite, TiO2 -coated Pt, TiO2 -coated RuO2 , and TiO2 were used as anode materials. Highest color removal with lowest energy consumption was achieved with TiO2 -coated RuO2 anode material (93.6%).

Design and Engineering of an Efficient Peroxidase Using Myoglobin for Dye Decolorization and Lignin Bioconversion.

The treatment of environmental pollutants such as synthetic dyes and lignin has received much attention, especially for biotechnological treatments using both native and artificial metalloenzymes. In this study, we designed and engineered an efficient peroxidase using the O2 carrier myoglobin (Mb) as a protein scaffold by four mutations (F43Y/T67R/P88W/F138W), which combines the key structural features of natural peroxidases such as the presence of a conserved His-Arg pair and Tyr/Trp residues close to the heme active center. Kinetic studies revealed that the quadruple mutant exhibits considerably enhanced peroxidase activity, with the catalytic efficiency (kcat/Km) comparable to that of the most efficient natural enzyme, horseradish peroxidase (HRP). Moreover, the designed enzyme can effectively decolorize a variety of synthetic organic dyes and catalyze the bioconversion of lignin, such as Kraft lignin and a model compound, guaiacylglycerol-β-guaiacyl ether (GGE). As analyzed by HPLC and ESI-MS, we identified several bioconversion products of GGE, as produced via bond cleavage followed by dimerization or trimerization, which illustrates the mechanism for lignin bioconversion. This study indicates that the designed enzyme could be exploited for the decolorization of textile wastewater contaminated with various dyes, as well as for the bioconversion of lignin to produce more value-added products.

Characterization and potential of two different anaerobic mixed microflora for bioenergy recovery and decolorization of textile wastewater: Effect of C/N ratio, dye concentration and pH

A series of standardized activity experiments were conducted to investigate the effect of the C/N ratio, dye concentration, and pH on the performance of two mesophilic mixed cultures for bioenergy production and decolorization of textile wastewater. The results showed that the most significant factor was the C/N ratio with LogWorth value of 9.961. The maximum methane yield reached 13.18 ± 0.64 mmoL/g COD with chemical oxygen demand (COD) degradation and decolorization of 84.32 and 98%, respectively under digested sludge. The propionate and butyric acid/acetic acid ratio were significantly affected by C/N ratio and the results of C/N ratio were explained by changes in the soluble by-products. The dye concentration of 100 mg/L yielded the highest biogas production with a maximum decolorization percentage. The digested sludge showed better performance under all tested conditions compared to granular sludge. Analysis of the data showed that the best condition was observed and the bioreaction was optimized.

The effect of different types of AOPs supported by hydrogen peroxide on the decolorization of methylene blue and viscose fibers dyeing wastewater.

Wastewater from the textile industry containing a high concentration of organic and inorganic chemicals has strong color and residual chemical oxygen demand (COD). Therefore, advanced oxidation processes (AOPs) are very good candidates to treat textile industry wastewater. In this study, we investigated the effect of different types of AOPs supported with hydrogen peroxide (H2O2) for the treatment of viscose fibers dyeing wastewater. Fenton, photo-Fenton, and Fenton-supported subcritical water oxidation (FSWO) processes were chosen as AOPs to compare the treatment efficiency of viscose fibers dyeing wastewater. The effects of solution pH, Fe2+ concentration, and H2O2 concentration on the treatment of viscose fibers dyeing wastewater were tested. The maximum color and COD removal efficiency was obtained corresponding to pH 2.5 for all oxidation methods when methylene blue (MB) dye solution was used. However, the maximum efficiencies were obtained at pH 3.0 for real textile wastewater decolorization. The MB dye removal efficiency was increased to 97.22, 100, and 100% for Fenton, photo-Fenton, and FSWO processes, respectively, when the addition of H2O2 concentration was adjusted to 125 mg/L. However, the maximum color removal efficiencies of viscose fibers dyeing wastewater were obtained 56.94, 61.26, 64.11% for Fenton, photo-Fenton, FSWO processes, respectively. As a result, the FSWO showed maximum color removal efficiencies.

Decolorization of Textile Wastewater with Activated Carbon made of Coconut Shell

This study focus on the removal of textile dyeing effluent by analyzing the physio-chemical parameters such as color, turbidity, pH, Chemical Oxygen Demand (COD). Activated carbon is used for removing color from the wastewater collected from silkworm textile industry, Bishnupur, West Bengal. We have used activated carbon made with coconut shell which is ecofriendly and low in cost. The results of the analysis were compared with the water quality standards of BIS (Bureau of Indian Standard) for further application of the treated water in agricultural field. Also, this paper included the case study on textile dyeing industry in Bankura district, West Bengal, India and its impacts of pollution load in the environment.

Glow-discharge plasma enhanced coating and functionalization of needle-punched nonwoven PET filter media for textile wastewater decolorization

This study reports the use of glow-discharge plasma coated and functionalized PET needle-punched nonwovens as filter media for decolorization of textile dye-containing effluent. The investigation had been aimed at proving the possibility of GDP enhanced coating and functionalization (GDP processing) to produce better results for successfully replace such thermochemical finishing of PEI coat onto the primary PET fibers. The fiber surfaces functionalization with branched polymers such PEI has aroused much interest recently due to their unique properties as dye-immobilization absorber. For this study, the effect of processing time on the dye retention capacity of the functionalized PET nonwovens was investigated. Comparison was made between the most influential parameters of the basic, chemically and GDP processed PET nonwovens, such as: material thickness, air permeability, and puncture strength. The dye-retention capacity of the basic and functionalized nonwovens was determined by two synthetic water effluent – the anionic Orange G and the cationic Methylene Blue test-dyes have been used. The normal glow-discharge plasma processing in air as residual gas at 80 Pa provide the best possible anionic dye retention capacity. Based on this study, it was confirmed that this PEI coated and functionalized PET nonwoven could be used for the immobilization of anionic dyes from colored textile wastewater: the retention capacity from 4.16 to 5.57 mg/g with is comparable to the other available products used as adsorbent in dye-immobilization wastewater treatment.

Iron Oxide/Chitosan Magnetic Nanocomposite Immobilized Manganese Peroxidase for Decolorization of Textile Wastewater

Because of its effectiveness in organic pollutant degradation, manganese peroxidase (MnP) enzyme has attracted significant attention in recent years regarding its use for wastewater treatment. Herein, MnP was extracted from Anthracophyllum discolor fungi and immobilized on the surface of magnetic nanocomposite Fe3O4/chitosan. The prepared nanocomposite offered a high surface area for MnP immobilization. The influence of several environmental factors like temperature, pH, as well as storage duration on the activity of the extracted enzyme has been studied. Fourier transmission infrared spectroscopy (FT-IR), scanning electron microscope (SEM), X-ray diffraction (XRD), and transmission electron microscope (TEM) techniques were used for the characterization of the prepared MnP/Fe3O4/chitosan nanocomposite. The efficiencies of the prepared MnP/Fe3O4/chitosan nanocomposite for the elimination of reactive orange 16 (RO 16) and methylene blue (MB) industrial dyes were determined. According to the results, the immobilization of MnP on Fe3O4/chitosan nanocomposite increases its capacity to decolorize MB and RO 16. This nanocomposite allowed the removal of 96% ± 2% and 98% ± 2% of MB and RO 16, respectively. The reusability of the synthesized nanocomposite was studied for five successive cycles showing the ability to retain its efficiency even after five cycles. Thus, the prepared MnP/Fe3O4/chitosan nanocomposite has potential to be a promising material for textile wastewater bioremediation.

High-rate anaerobic decolorization of methyl orange from synthetic azo dye wastewater in a methane-based hollow fiber membrane bioreactor

Anaerobic biological techniques are widely used in the reductive decolorization of textile wastewater. However, the decolorization efficiency of textile wastewater by conventional anaerobic biological techniques is generally limited due to the low biomass retention capacity and short hydraulic retention time (HRT). In this study, a methane-based hollow fiber membrane bioreactor (HfMBR) was initially inoculated with an enriched anaerobic methane oxidation (AOM) culture to rapidly form an anaerobic biofilm. Then, synthetic azo dye wastewater containing methyl orange (MO) was fed into the HfMBR. MO decolorization efficiency of ∼ 100 % (HRT = 2 to 1.5 days) and maximum decolorization rate of 883 mg/L/day (HRT = 0.5 day) were obtained by the stepwise increase of the MO loading rate into the methane-based HfMBR. Scanning electron microscopy (SEM) and fluorescence in situ hybridization (FISH) analysis visually revealed that archaea clusters formed synergistic consortia with adjacent bacteria. Quantitative PCR (qPCR), phylogenetic and high-throughput sequencing analysis results further confirmed the biological consortia formation of methane-related archaea and partner bacteria, which played a synergistic role in MO decolorization. The high removal efficiency and stable microbial structure in HfMBR suggest it is a potentially effective technique for high-toxic azo dyes removal from textile wastewater.

Comparative Studied of Degradation of Textile Brilliant Reactive Red Dye Using H2O2, TiO2, UV and Sunlight

In this study sunlight and UV radiation were used to compare the efficiency of decolorization of textile wastewater containing brilliant reactive red dye K-2BP (?max = 534 nm) by the advanced oxidation process (AOP) using (H2O2/sunlight, H2O2/UV, H2O2/TiO2/sunlight, and H2O2/TiO2/UV). The results studied the effect of solution pH, applied H2O2 concentration, TiO2 concentration (nanoparticle), and initial dye concentration were studied. The experimental results showed that decolorization percentage with H2O2/sunlight and TiO2/H2O2/sunlight under the following conditions: - reaction time 150 of minutes, [ 500 ppm] H2O2, [100 ppm] TiO2, pH=3, initial dye concentration =15 ppm and at ambient temperature were 95.7% and 98.42% respectively. For the same conditions using H2O2/UV, H2O2/TiO2 /UV, the percentage of decolorization were 97.85% and 96.33% respectively. The results also indicated that the sunlight is more economic and cost-effective than UV radiation.

Investigation of Some Parameters Affecting Methyl OrangeRemoval by Fusarium acuminatum

ABSTRACT Dye stuff released to the ecosystem from textile industries cause a serious contamination and become a major environmental problem over the last few decades. As biological decolorization of textile wastewater is an important issue, Fusarium . acuminatum was used to removal of a frequently used textile dye, methyl orange. Live pellet of Fusarium acuminatum was used and decolorization studies performed in various temperatures and pH conditions with different dye concentrations. The highest decolorization rate was observed at 35ᴼC. 60 mg/L was found as the optimum initial dye concentration. In the pH range of 3-4, decolorization rate was approximately 70%. It was seen that Fusarium acuminatum have the great ability of the methyl orange removal. To our knowledge, it took place for the first time in the literature.

Investigation of dye removal with isolated biomasses from whey wastewater

In this work, as a new eco-friendly biosorbent, the removal of textile wastewater was carried out by biomass of mesophilic and thermophilic lactic acid bacteria (LAB), which form the natural flora of whey. Mesophilic and thermophilic LAB provide a wide variety of properties in the taste and texture of food products through the fermentation of raw materials in the production of dairy products. Whey is produced as waste after dairy products are produced. Decolorization tests of Dorasyn Red azo dye, which is widely used in the textile sector, have been carried out by obtaining biomass with LAB isolated from whey. Thus, the recovery of whey, which is accepted as waste, has been achieved. In this study, parameters affecting the dissociation reaction of different pH and biomass concentrations were investigated. The dye removal test for four different LAB biomasses (mesophilic lactobacilli and lactococci, and thermophilic lactobacilli and lactococci) was performed at ten different concentration levels (0, 0.5, 0.75, 1, 1.25, 1.5, and 5 g/L). The pH value was adjusted to pH 3 and 6.8 (original) and incubated for 3 h at 20 °C. Tested pH values were 1.5, 2, 3, 4, 5, 6, 7, 8, 9, and 10 with constant 2.5 g/L biomass concentration. Decolorization efficiencies for about 90% dye removal were obtained with mesophilic lactobacilli biomass (2.5 g/L) at pH 3 after 3-h reaction time. This study presents a report that the whey for environmental protection and paint recovery is an appropriate alternative to the decolorization of textile wastewater.

Decolorization of Textile Wastewater Using Fabricated Poly Acrylonitrile (PAN) Nanoparticles

Water contamination is not only influence human health and environment, but it has alsoeffects on social and economic costs. Textile wastewater is considered to be one of the mostdangerous types of water contaminants as it consists of mixture of pigments, dyes and differenttypes of organic contaminants. Nanotechnology offers novel functional materials in the area ofwastewater treatment especially dye removal. Polyacrylonitrile (PAN) nanoparticles considered tobe one of the most promising prepared materials in the field of dye removal. PAN nanoparticleswas prepared by precipitation polymerization technique in an alcoholic aqueous solution (water:ethanol) and was characterized using scanning electron microscope (SEM), Fourier Transferinfrared spectrophotometer (FT-IR) and Thermal Gravimetric Analysis (TGA). Basic Red 46 (BR46) dye is a cationic dye which is used as a model of contaminant due to its extensive use intextile industry. The processing parameters affecting on the adsorption of BR 46 onto theprepared PAN nanoparticles have been optimized through a batch mode experiments.The maximum removal percentage of the selected dye was 62.4 % recorded after 240 minequilibrium time using 0.05 g from PAN nanoparticles and with 5 ppm initial dye concentration.As the experimental results proved that the increment in material dosage from 0.01 to 0.5 genhanced the dye removal percentage from 43.6% up to 85%. Meanwhile, the improvement ininitial dye concentrations had negative impact on the adsorption process onto the preparedpowdered material, as it decreased from 82.3 to 11.85% when the initial dye concentrationincreased from 1-100 ppm. The dye adsorption mechanism was investigated through theapplication of Langmuir and Freundlich isotherm models on the experimental data. Moreover, thekinetics of dye adsorption process was tested using the pseudo-first and pseudo-second orderkinetic models.

/+//Biodecolorization of Reactive Black5 and Reactive Red120 azo dyes using bacterial strains isolated from dairy effluents

In a biological treatment of an industrial effluent, the indigenous bacteria have already been used. In this study, the three bacteria strains which are potent in the decolorization of azo dyes were isolated from dairy effluent and used for decolorization of Reactive Black5 and Reactive Red120 azo dyes and decolorization test of each dye was conducted at five concentration levels (10, 50, 100, 150, and 200 mg/l). The pH of which was adjusted to 7 and incubated at 37 °C for 3 days. The strains were identified as Staphylococcus sp. and Micrococcus luteus strains by 16S rRNA gene sequences analysis. The strains were deposited in GenBank with accession numbers of KX180131, KX180132, and KX180133 and submitted to laboratory identifier named Staphylococcus sp. MEH038S, Micrococcus luteus strain SEH038S, and Micrococcus luteus strain FEH038S. Three days into incubation, the lowest efficiency was at a concentration level of 200 mg/l for each dye. Decolorization efficiencies for Staphylococcus sp. MEH038S, Micrococcus luteus strain SEH038S, and Micrococcus luteus strain FEH038S at the concentration level of 200 mg/l for Reactive Red120 were 89.7, 87.1, and 89.3%, and for Reactive Black5 were 90.8, 90.0, and 89.9%, respectively. Based upon this study, dairy effluents can be used as a suitable alternative to the decolorization of textile wastewater. This study demonstrates a report on grounds of elucidation for the use of non-indigenous bacteria in the treatment of industrial wastewater.