Textile Dyeing Wastewater Research Articles

Monitoring and assessment of Dracaena-based constructed vertical flow wetlands treating textile dye wastewater.

The monitoring and assessment of multiple constructed vertical flow wetlands (CVFWs) treating textile dye wastewater (metanil yellow as dye) are studied covering three seasons. Three CVFWs (CVFW-1, dye—5 mg/l; CVFW-2, dye—50 mg/l; and CVFW-3, dye—100 mg/l) and a control (dye—5 mg/l) were used. The CVFWs with Dracaena (an ornamental plant) efficiently removed contaminants like dye, COD, NH4+-N, and PO43−-P from the wastewater under varying inlet dye concentrations, indicating its dependence on meteorological conditions. Substantial dye removal was observed to be maximum in summer (control, 44.3%; CVFW-1, 75.1%; CVFW-2, 76.1%; CVFW-3, 46%), but lesser in winter (control, 45%; CVFW-1, 73.1%; CVFW-2, 76.8%; CVFW-3, 42.6%) and minimum in monsoon (control, 40.8%; CVFW-1, 63.5%; CVFW-2, 51.6%; CVFW-3, 37.1%), respectively. Efficiency was less in CVFW-3 as it observed plant stress due to higher inlet dye concentration. COD removal was higher in winter, followed by summer and monsoon. A first-order kinetic model was used to investigate the efficiency of the CVFW system w.r.t. contaminant removal. Various functional groups were characterized using Fourier transform infrared spectroscopy (FTIR) from the inlet and outlet water samples of different CVFWs. The Dracaena accumulated various elements and oxides during the treatment with no stress on its health. No effects on plant health highlight the suitability of Dracaena for textile wastewater treatment. The results were validated using statistical tools like the Mann–Whitney U test and principal component analysis (PCA).Supplementary InformationThe online version contains supplementary material available at 10.1007/s10661-022-10415-y.

A Composite Fabric with Dual Functions for High-Performance Water Purification.

The dilemma of diminishing freshwater resources caused by water pollution has always impacted human life. Solar-driven interfacial evaporation technology has the potential for freshwater production via solar-driven distillation. However, in solar-driven interfacial evaporation technology, it is difficult to overcome the problem of wastewater containing various contaminants. In this work, we propose a bifunctional fabric created by depositing titanium dioxide@carbon black nanoparticles onto cotton fabric (TiO2@CB/CF). The TiO2@CB/CF has a coupling effect that includes the photothermal effect of CB and photocatalysis of TiO2, and it can not only generate clean water but can also purify contaminated water. The resulting bifunctional fabric can achieve an outstanding water evaporation rate of 1.42 kg m−2 h−1 and a conversion efficiency of 90.4% in methylene blue (MB) solution under one-sun irradiation. Simultaneously, the TiO2@CB/CF demonstrates a high photocatalytic degradation of 57% for MB solution after 2 h with light irradiation. It still shows a good photocatalysis effect, even when reused in an MB solution for eight cycles. Furthermore, the TiO2@CB/CF delivers excellent performance for actual industrial textile dyeing wastewater. This bifunctional fabric has a good application prospect and will provide a novel way to resolve the issue of freshwater scarcity.

MoSe2-modified ZIF-8 novel nanocomposite for photocatalytic remediation of textile dye and antibiotic-contaminated wastewater.

COVID-19-led antibiotic waste generated from hospitals and health centres may cause serious health issues and significantly impact the environment. In the coming decades, antibiotic resistance will be one of the most significant threats to global human health. Photocatalytic water remediation is an effective and promising environmental solution that can be utilized to address this issue, to convert antibiotic waste into non-toxic products by utilizing renewable and abundant solar energy. In the present study, a novel nanocomposite of zeolitic imidazolate frameworks (ZIF-8) and molybdenum diselenide (MoSe2) was efficiently synthesized by the solvothermal method for the complete degradation of the antibiotics and textile waste from water. The morphology, crystallinity and band gap of the samples were characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and UV–visible spectroscopy. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) provide the binding information of the sample. The photocatalytic activity was tested for degradation of the antibiotics (tetracycline hydrochloride (TC) and metronidazole (MNZ)) used in COVID-19 treatment and textile dye (malachite green). Time-resolved photoluminescence spectroscopy confirmed the enhanced charge separation in the MoSe2@ZIF-8 nanocomposite with an average lifetime of 4.72 ns as compared to pristine samples. The nanocomposite showed ~ 100% removal efficiency with rate constants of 63 × 10−3, 49 × 10−3 and 42 × 10−3 min−1 for TC, MNZ and malachite green, respectively. The photocatalytic degradation of TC was carried out under different pH conditions (4, 7 and 9), and the degradation mechanism was explained on the basis of zeta potential measurements and active species trapping experiment. The by-products of the photocatalytic treatment of TC antibiotics were tested using liquid chromatography-mass spectroscopy (LC–MS), and they were found to be non-toxic for aquatic and human life. The regeneration property of the nanocomposite was confirmed by FESEM with regeneration efficiency of 88.7% in the 4th cycle. Thus, MoSe2@ZIF-8-based photocatalysts have potential application in water remediation, especially in making the antibiotic waste less toxic.

Biochemical and molecular characterization of a new heme peroxidase from Aspergillus niger CTM10002, and its application in textile reactive dye decolorization

The presence of textile dyes in wastewater of textile factories represents a major environmental problem, threatening aquatic life. The decolorisation and degradation of harmful textile-dyes therefore remains a key field of research. In this study, a novel extracellular heme-manganese-peroxidase (30 kDa-MnP AN30) produced by Aspergillus niger strain CTM10002, a strain which was isolated from contaminated-wastewater of a nitrogen-phosphate-potash (NPK) chemical company in Sfax (Tunisia), was evaluated for its efficiency in the decolorization of different textile-dyes. Purification yield reached 60%, with a specific activity of 372 U/mg and Reinheitzahl (RZ) value of 2.8 under the optimal conditions of 40 °C and pH 5. The MnP AN30 NH2-terminal sequence was characterized by a high degree of similarity with those of other fungal-peroxidases. The mnp AN30 gene was cloned, sequenced, and expressed in Escherichia coli strain BL21(DE3)pLysS. Biochemical properties of the recombinant enzyme (rMnP AN30) were similar to those of the native one. Interestingly, molecular modeling and docking of MnP AN30 heme binding site revealed the involvement of 19 amino acid residues in substrate binding. More interestingly, MnP AN30 is capable of decolorizing textile dyes with higher decolorization efficiency than MnP TC55 from Trametes pubescens strain i8. Accordingly, these properties showed the potential candidacy of MnP AN30 to be used in biological treatment and decolorization of synthetic textile dyes.

Highly efficient adsorption of dye using novel reduced graphene oxide/halloysite nanocomposite

The novel composite nanomaterials were synthesized via a simple method from two natural clay mineral sources, graphite and halloysite. The materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR), Brunauer-Emmet-Teller (BET) methods. The results showed that halloysite nanotubes are successfully intercalated between the graphene oxide layers. The adsorption capacity of the material with RY-145, a typical dye in textile wastewater, was evaluated. Also, the effects of adsorption time, initial concentration of pollutant, adsorbent dosage, speed of agitation and temperature were investigated. The adsorption efficiency of the material for RY-145 dye is about 99% after 4 hours with the high initial concentration of pollutant of 50ppm. Adsorption kinetics of the material for RY-145 match the pseudo-second order kinetic of Langmuir adsorption model. The outstanding performance of the nanocomposite as an adsorbent highlight the promising applications of the novel material in was water treatment processes.

Optimization for minimizing the cost of ozonation of highly concentrated textile dyeing wastewater in a bubble column reactor.

Ozonation is one of the advanced oxidation methods that provide effective decolorization and detoxification of the dyeing wastewater without causing any sludge formation. Despite being a good alternative to biodegradation, ozonation suffers from a high operating cost. This study conducted the ozonation process at high initial dye concentrations and optimized the process parameters (such as initial ozone concentration, initial dye concentration, and pH) to minimize the operating cost in terms of the overall power consumption of the process. The ozonation of Reactive Blue dye was performed in a bubble column reactor at various process conditions. A central composite design (CCD)-based response surface method (RSM) statistical tool was used to optimize the process. An empirical correlation for the specific power consumption (defined as electricity consumed per unit mass of dye removed from a unit volume of dyeing wastewater) was developed and verified. It was found that the specific power consumption during ozonation can be lowered significantly (by ~25-30%) if the dyeing water was treated at high initial dye concentrations.

Textile dyeing wastewater treatment by Penicillium chrysogenum: Design of a sustainable process.

In this work a parametric study and a bench bioreactor degradation test of Direct Black 22 (DB22) by Penicillium chrysogenum was performed as a first approach to an industrial application, framed within a policy of sustainable processes development. Three ancillary carbon sources and their optimum initial concentrations were studied. These were: glucose, potato starch and potato industry wastewater. Their optimum initial concentration was 6 g/L. The use of potato starch as co-substrate showed the highest decolorization rate and COD removal. Degradation of DB22 using different immobilization supports (stainless steel sponge, loofah sponge and polyethylene strips) was studied and the results showed that the time needed for the treatment decreased from 6 to 4 d. Phytotoxicity was evaluated in the final products of the immobilized cells assays, using Lactuca sativa seeds. For all treatments phytoxicity was reduced with respect to the untreated wastewater, except for the assays using polyethylene strips. Finally, the reuse of the biomass attached to different carriers and the performance of the treatment of DB22 in a 1 L bench scale bioreactor were tested. P. chrysogenum decolorized at least four sucesives reuses. The reactor assays showed a better performance of the treatment.

Optimizing textile dyeing wastewater for tomato irrigation through physiochemical, plant nutrient uses and pollution load index of irrigated soil

Reuse of wastewater for vegetable cultivation is becoming popular in order to augment the inadequate irrigation supplies and meet the growing demands of ground water for agriculture and industries production in different regions of the world. This study was investigated to optimize different stages of textile dyeing wastewater (TDW) for irrigation focusing on their effect on growth, yield and physiochemical attributes of tomato, plant nutrient use, heavy metals enrichment and pollution load of the irrigated soil. Textile wastewater were collected from the seven stages of (second wash after scouring and bleaching T2; enzyme treated water T3; second wash after bath drain T4; neutralization treatment T5; second wash after soaping T6; fixing treatment water T7; mixed effluent T8) of a dyeing process for physiochemical characterization and evaluation their irrigation feasibility for tomato cultivation in compare with the ground water (T1). The pot experiment consists of eight irrigation treatments was laid out following a completely randomized block design with three replications. Results showed the presence of plant nutrients and heavy metals in all the studied samples where T8 (mixed effluent) exceeded the limit of agricultural standard for almost all physiological parameters such as TDS, TSS, EC, BOD, COD affording the highest value. T8 also delivered the highest Cl- and heavy metals like Cd, Ni, Cr followed by T4 < T7. As a consequence, these provided comparatively higher enrichment factor (EF), pollution load index (PLI) and sodium absorption ratio (SAR) to transform fresh soil into the category of severe and slightly to moderate saline. Therefore, the yield and physiochemical attributes of tomato were dramatically reduced with T8 and T4 treatment. On the other hand, T2, T3 and T6 treatment had significant positive impact on growth and yield of tomato due to having higher N, P, K, S and lower heavy metals (Cu, Zn, Fe, Pb, Cd, Ni, Cr) than the recommended guideline. These features were contributed to cause minimum EF and PLI in the soil irrigated with T2, T3 and T6 stages of TDW. Correlation matrix demonstrated that EF and PLI of heavy metals (except Cd, Ni) were negatively related to yield, while positively related to SAR and fruit abortion. Although T6 (2nd wash after soaping) performed better in respect to growth, yield, yield attributes and nutrient use efficiency, principal component analysis revealed that T2 (2nd wash after scouring and bleaching) and T3 (enzyme treated water) were also belong to the same group of T6 and T1 (ground water). Thus, it may be suggested that T2, T3 and T6 stages of textile dyeing wastewater could be used profitably without ETP for vegetable cultivation and would effectively supplement not only the nutrient requirement of the crop but may also act as the alternate source of irrigation water. Although, further research is needed to sort out the health risk assessment through the heavy metals’ accumulation in the plant parts after irrigation with different stages of textile dyeing wastewater.

Synthesis of rGO/g-C3N4 for methyl orange degradation in activating peroxydisulfate under simulated solar light irradiation

• Metal-free rGO/g-C 3 N 4 composite was synthesized successfully by a simple polymerization-hydrothermal method. • rGO/g-C 3 N 4 /PDS system exhibited superior degradation efficiency of MO under stimulated solar light irradiation. • SO 4 ¯ · , h + , O 2 ¯ · and non-radical reaction pathway were involved in the removal of MO. In this study, reduced graphene oxide-based graphitic carbon nitride (rGO/g-C 3 N 4 ) composite was fabricated via thermal polymerization-hydrothermal method and were utilized to activate peroxydisulfate (PDS) under simulated solar light irradiation. The as-synthesized rGO/g-C 3 N 4 was demonstrated to effectively remove methyl orange (MO) in wastewater. Notably, 92.3% of MO (15 mg/L) was removed within 120 min in the presence of 0.2 g/L rGO/g-C 3 N 4 and 0.225 g/L PDS. The influence of activator dosage, PDS concentration and co-existing solution matrix on the removal efficiency was investigated. Free radical capture experiments confirmed that SO 4 ¯ · , photogenerated holes (h + ), O 2 ¯ · and non-radical reaction initiated by rGO played a major role in MO removal. Furthermore, PDS and rGO acted as the electron acceptor and transfer carrier of the photogenerated charges, respectively, resulting in the efficient activation of PDS. The promoting visible light absorption might be ascribed to the defect sites on the surface of rGO/g-C 3 N 4 , which generated from the rGO loading. This study revealed that the as-synthesized rGO/g-C 3 N 4 composite exhibits wide promising application prospects as a photocatalytic activator of PDS for the degradation of azo dyes in textile wastewater.

Biodegradation of Textile Dye Wastewater with the Application of Response Surface Methodology (RSM): A Factorial Design Approach

The increasing demands in textile industries has created huge production of textile coloured products globally, leading to large production of textile effluent. Textile effluent is often discharged to the environment without proper treatment by the textile factories. The untreated textile effluent typically contains harmful chemicals and is hazardous to the environment, due to the toxicity of the dyes used. In this study, biological treatment is applied to the textile effluent. A 2-level full factorial design from response surface methodology (RSM) was applied to find the optimized treatment process condition for the textile wastewater degradation. Sixteen runs of experiment with 4 factors were performed; bacterial inoculum (%, v/v), temperature (℃), agitation (rpm), and pH were tested. It was observed highest decolourization obtained (91.95 % with pH 4, low concentration of bacterial inoculum (5 %), agitation speed (200 rpm) and temperature (40 ℃)) meanwhile lowest decolourization was achieved at 73.47 % with pH 10, low concentration of bacterial inoculum (5 %), agitation speed (100 rpm) and high temperature (40 ℃). It was observed that low concentration of bacterial inoculum (%, v/v) gave more favourable dye degradation and COD removal, while pH ranged from low to high in the textile dye treatment.&#x0D; HIGHLIGHTS&#x0D; &#x0D; Textile wastewater contributes the most in Sg. Hiliran, as textile wastewater was discharged directly into the river without proper treatment&#x0D; Biodegradation using a bacterial approach offers safe and costly effective treatment for the textile wastewater&#x0D; The application of RSM offers a practical approach in providing optimized parameters for the textile wastewater treatment&#x0D;

Intensification of ozone mass transfer for wastewater treatment using a rotating bar reactor

As one of the advanced oxidation processes (AOPs), ozonation has been widely used in the treatment of textile dyeing wastewater. However, ozonation was limited by the mass transfer process due to the low solubility of ozone in water. In this work, a novel rotating bar reactor (RBR) was developed to enhance ozone-water mass transfer via optimizing its inner structures. The RBR with the internal structure of sieve plates combined with spoiler columns has the best mass transfer performance, which was 249% higher than that of the RBR without these structures. Furthermore, the optimized RBR was adopted to intensify the decolorization of the simulated wastewater of reactive black 5. The ozone dose was used to characterize the introduced ozone mass for treating a liter of wastewater in different reactors. The ozone dose in RBR was 150 mg/L (using O3), which was lower than that in semibatch glass reactor (567 mg/L, using O3/UV/H2O2) and in cylindrical glass cell (506.67 mg/L, using O3/US), reported in the literatures. The results indicated that RBR can achieve the same decolorization rate with less ozone dose, i.e. the RBR is more efficient. The RBR exhibited great potential application in enhancing liquid-film controlling system.

Reuse of Textile Dyeing Wastewater Treated by Electrooxidation

Wastewater reuse has been addressed to promote the sustainable water utilization in textile industry. However, conventional technologies are unable to deliver treated wastewater with the quality required for reuse, mainly due to the presence of dyes and high salinity. In this work, the feasibility of electrooxidation, using a boron-doped diamond anode, to provide treated textile dyeing wastewater (TDW) with the quality required for reuse, and with complete recovery of salts, was evaluated. The influence of the applied current density on the quality of treated TDW and on the consecutive reuse in new dyeing baths was studied. The ecotoxicological evaluation of the process towards Daphnia magna was performed. After 10 h of electrooxidation at 60 and 100 mA cm−2, discolorized treated TDW, with chemical oxygen demand below 200 (moderate-quality) and 50 mg L−1 (high-quality), respectively, was obtained. Salt content was unchanged in both treatment conditions, enabling the consecutive reuse without any salt addition. For the two reuse cycles performed, both treated samples led to dyed fabrics in compliance with the most restrictive controls, showing that an effective consecutive reuse can be achieved with a moderate-quality water. Besides the water reuse and complete salts saving, electrooxidation accomplished an ecotoxicity reduction up to 18.6-fold, allowing TDW reuse without severe ecotoxicity accumulation.

A novel and one-pot synthesis of Punica granatum mediated copper oxide having flower-like morphology as an efficient visible-light driven photocatalyst for degradation of textile dyes in waste water

Removal of an organic pollutant from wastewater is becoming a matter of serious concern due to pure water scarcity. The present research proposed a one-pot synthesis of CuO nanoparticles with a novel flower-like morphology which is found to be an efficient photocatalyst for the current scenario of environmental concern i.e., degradation of organic pollutants. Nanoparticles have been successfully synthesized using Punica granatum leaf extract as a stabilizing and reducing agent and are characterized through XRD, FTIR, FESEM, EDX, TEM, and UV–Visible spectrophotometer. XRD pattern elucidates the formation of green synthesized CuO along with the coexistence of cubic-Cu2O and monoclinic-CuO phases. FTIR and EDS results enumerate the presence of biomolecules of leaf extract on the particle’s surface of CuO and elemental composition, respectively. FESEM images depict different flower-like morphology. TEM images expose the interspaces among the particles which result in high absorption of dye-molecules. HRTEM reveals the interplanar distance of 0.24 nm corresponding to (111) lattice plane of CuO. BET results reveal mesoporous nature of copper oxide particles with surface area and pore size of 85.551 m2g−1 and 9 nm. TG-DTA analysis reveals the formation of stable CuO. Effect of pH, copper oxide dose, dye concentration and contact time on the adsorption of dye has been studied along with adsorption isotherms. High photocatalytic efficiency (97.8%, 90.8% and 93%) of such type of morphology of CuO has been achieved under natural sunlight towards decolorization of three different type dyes (Reactive Yellow-86, Reactive Orange-4 and Methylene Blue). Therefore, current work offers simplistic, rapid, and eco-friendly green synthesis of CuO. This study will contribute in its own way for the practical development of the green synthesis route.

A novel route to the synthesis of α-Fe2O3@C@SiO2/TiO2 nanocomposite from the metal-organic framework as a photocatalyst for water treatment

In this study, an attempt was made to synthesize metal-organic frameworks (MOFs) based magnetic iron particles as photocatalysts for textile dye wastewater. Improvement strategy was a novel two-step dry method without using conventional methods to eliminate the consumption of chemical reagents. First, the heterogeneous photocatalyst of Fe-MOFs derived magnetic carbon nanocomposite with carboxylic acid surface functional groups (Fe@C–COOH) was achieved. Next, the α-Fe2O3@C@SiO2/TiO2 was successfully synthesized followed by a sol-gel method to coat the SiO2 shell and a solvothermal method to coat the surface of the intermediate TiO2 particles. The as-synthesized nanocomposite materials were characterized and physicochemical analytical equipment. Further, the investigation on magnetic photocatalytic nanocomposite α-Fe2O3@C@SiO2/TiO2 performance of dye degradation and photocatalytic activity on Reactive yellow 145 (RY145), using as an indicator was conducted. The as-synthesized nanocomposite particles were characterized using X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FT-IR), vibrating sample magnetometer (VSM), X-ray energy dispersive spectroscopy (EDX), and scanning electron microscopy (SEM) techniques. The structural characterization of the as-synthesized materials proved that these methods generate oxygen-containing functional groups, such as, –OH, –CO, and –COOH, which increases the polarity and hydrophilicity of the photocatalyst. The photocatalytic oxidation of RY145 dye under UVc light was discussed by the apparent first-order reaction rate and the kinetic model of the Langmuir-Hinshelwood followed a better fitting. The optimal performance of the composite is at pH = 2, 15 mg/100 mL of photocatalyst dose, 150 mg/L concentration of the dye RY145 at 25 °C temperature under UVc lamp irradiation for 90 min, and with the apparent reaction rate constant was 0.0165 min−1. The thermodynamic analysis of activation parameters computed by the Eyring model and based on transition state theory (TST), an endothermic reaction with a positive value for Δ‡Ho (50.16 kJ mol−1) and a negative value for Δ‡So (−153 J/mol K) both contribute toward achieving positive values for Δ‡Go and a nonspontaneous process. The proposed α-Fe2O3@C@SiO2/TiO2 demonstrated a high capability of photocatalytic degradation up to 97% after five successive cycles at the optimal condition compared to that of Fe3O4@C (18.74%) and Fe@C–COOH (77.9%) without reusability.

Exploring the potential of a newly constructed manganese peroxidase-producing yeast consortium for tolerating lignin degradation inhibitors while simultaneously decolorizing and detoxifying textile azo dye wastewater

MnP-YC4, a newly constructed manganese peroxidase-producing yeast consortium, has been developed to withstand lignin degradation inhibitors while degrading and detoxifying azo dye. MnP-YC4 tolerance to major biomass-derived inhibitors was promising. MnP induced by lignin was found to be highly related to dye decolorization by MnP-YC4. Simulated azo dye-containing wastewater supplemented with a lignin co-substrate (3,5-Dimethoxy-4-hydroxybenzaldehyde) decolorized up to 100, 91, and 76% at final concentrations of 20, 40, and 60%, respectively. MnP-YC4 effectively decolorized the real textile wastewater sample, reaching up to 91.4%, and the COD value decreased significantly during the decolorization, reaching 7160 mg/l within 7 days. A possible dye biodegradation pathway was proposed based on the degradation products identified by UV–vis, FTIR, GC/MS, and HPLC techniques, beginning with azo bond cleavage and eventually mineralized to CO2 and H2O. When compared to the phytotoxic original dye, the phytotoxicity of MnP-YC4 treated dye-containing wastewater samples confirmed the nontoxic nature.

Study on the Flocculation Performance of a Cationic Starch‐Based Flocculant on Humic Substances in Textile Dyeing Wastewater

AbstractDissolved organic matter is one of the difficult problems in the treatment of textile dyeing wastewater, among which humic substances are the most harmful to the environment and human health. Herein, cationic starch‐based flocculants are prepared by free radical polymerization of corn starch (St) and methacryloyloxyethyl trimethyl ammonium chloride (DMC) in a redox‐initiated system of ammonium persulfate and sodium bisulfite. Corn starch‐graft‐poly(methacryloyloxyethyl trimethyl ammonium chloride) is denoted as St‐g‐PDMC. The St‐g‐PDMC is comprehensively characterized in terms of structural (element analysis, Fourier transform infrared, X‐ray diffraction, proton nuclear magnetic resonance spectroscopy), morphological (scanning electron microscopy), and thermal (differential scanning calorimetry) properties. Humic acid (HA) solution is selected to simulate negatively charged dissolved organic matter. The flocculation performance and mechanism of St‐g‐PDMC, cationic polyacrylamide (CPAM), and polymerized aluminum chloride (PAC) are systematically investigated. The experimental results show that St‐g‐PDMC functions mainly through the electric neutralization and bridging effect as the flocculation mechanism, CPAM using its own structure and the colloid formed by PAC through hydrolysis is more in line with the bonded bridging and net roll sweep trapping. The combined formulation of St‐g‐PDMC and PAC shows advantages over a single flocculant in the treatment of textile dyeing wastewater, and its cost is evaluated.

A Sustainable Approach in Bioremediation of Textile Dye Effluent by Microbial Consortia

Abstract: The humongous load on the environment due to the expulsion of textile dye wastewater has always been a major issue. Significantly, the dye is present in the wastewater due to its complex chemical structure, making it a recalcitrant pollutant. Therefore, becoming highly noxious to flora and fauna of the aquatic ecosystems and crop plants. Due to the low biodegradability, dyes are carcinogenic and mutagenic to plants and human beings. Various physicochemical strategies to treat textile effluent have been used, but because of several drawbacks, they are not implemented by most industries. Microbial decolorization is more eco-compatible and economical as it does not produce any intermediate by-products. Also, it can mineralize the dyes completely and efficiently. Microbes like bacteria, fungi, and algae possess enzymes capable of degrading dyes. These organisms are now in trend with the utilization of mixed culture in comparison to the use of individual strain. Bioremediation of pollutants reduces the toxicity from the soil and water source so that water used for irrigation will no longer be harmful to the plants and eventually to us. Keywords: Textile, effluent, bioremediation, decolourization, pollutants

Treatment of Blue HB Reactive Dyes in Textile Wastewater using Bio-waste based Hydroxyapatite

Treatment of Blue HB Reactive Dyes in Textile Wastewater using Bio-waste based Hydroxyapatite

Synthesis and Characterization of Poly(o-chloroaniline)/TiO2 Nanocomposites for Photocatalytic Degradation of Direct Yellow 50 Dye in Textile Wastewater

&lt;p&gt;The nanocomposites of poly(o-chloroaniline) with titanium dioxide have been prepared via chemical oxidative polymerization technique using o-chloroaniline monomer and titanium dioxide nanoparticles for photocatalytic application. The different composites were prepared by varying the load percentage of titanium oxide nanoparticles (TiO2 NPs) in polyorthochloroaniline (POCA) matrix. The synthesized composite materials were characterized by Scanning electron microscopy (SEM), X-Rays diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) techniques. The POCA/TiO2 nanocomposites were further applied to evaluate the photocatalytic degradation potential towards direct yellow 50 (DY50) dye in an aqueous medium under ultraviolet radiations.&lt;/p&gt;&#x0D;

Kinetics and Performance of Biological Activated Carbon Reactor for Advanced Treatment of Textile Dye Wastewater

The kinetics and performance of a biological activated carbon (BAC) reactor were evaluated to validate the proposed kinetic model. The Freundlich adsorption capacity (Ka) and adsorption intensity constants (n) obtained from the batch experiments were 1.023 ± 0.134 (mg/g) (L/mg)1/n and 2.036 ± 0.785, respectively. The effective diffusivity (Ds) of the substrate within the activated carbon was determined by comparing the adsorption model value with the experimental data to find the best fit value (4.3 × 10–4 cm2/d). The batch tests revealed that the yield coefficient (Y) was 0.18 mg VSS/mg COD. Monod and Haldane kinetics were applied to fit the experimental data and determine the biokinetic constants, such as the maximum specific utilization rate (k), half-saturation constant (KS), inhibition constant (Ki), and biomass death rate coefficient (kd). The results revealed that the Haldane kinetics fit the experimental data better than the Monod kinetics. The values of k, KS, Ki, and kd were 3.52 mg COD/mg VSS-d, 71.7 mg COD/L, 81.63 mg COD/L, and 4.9 × 10−3 1/d, respectively. The BAC reactor had a high COD removal efficiency of 94.45% at a steady state. The average influent color was found to be 62 ± 22 ADMI color units, and the color removal efficiency was 73–100% (average 92.3 ± 10.2%). The removal efficiency for ammonium was 73.9 ± 24.4%, while the residual concentration of ammonium in the effluent was 1.91 ± 2.04 mg/L. The effluent quality from the BAC reactor could meet the discharge standard and satisfy the reuse requirements of textile dye wastewater.