Pollutants In Textile Wastewater Research Articles

Generation of H2O2 via simultaneous treatment of cotton and organic pollutants in textile wastewater

The textile industry is essential for human life but generates significant amounts of waste cotton and alkaline dye wastewater. These pollutants are difficult to separate and treat, causing numerous environmental issues. Traditional methods struggle to deal with the combined pollution without additives. In this study, we developed a simple hydrothermal process to convert waste cotton and dye wastewater into a non-metal catalyst. This catalyst can degrade dyes using oxygen from the air. Remarkably, it produces a substantial amount of H2O2 after degrading the dyes. This demonstrates that we utilized waste cotton present in textile wastewater as a catalyst precursor and abundant oxygen as an oxidant to convert dye wastewater into valuable H2O2. We also used commercially available cotton cloth as a raw material and achieved good results. Under the optimized conditions, 96 % of the dye was degraded within 4 h, generating 252 μM of H2O2 simultaneously. Additionally, the catalysts performed better under alkaline conditions, with the dye degradation rate increasing by 33 % compared to neutral conditions. This is ideal for alkaline textile mill wastewater. Therefore, our work provides a novel method for the treatment of cotton waste and dyes in textile mills and has broad application prospects.

Removal of mixed pollutants of perfluorooctanoic acid and 2,4,6-trichlorophenol via adsorption-photocatalysis using Ga2O3-Bi4O7 combining with fluorine-doped covalent triazine framework: Role of different active species

Perfluorooctanoic acid (PFOA) and 2,4,6-trichlorophenol (2,4,6-TCP) are significant pollutants found in textile wastewater, posing severe threats to ecological environments. The construction of an adsorption-photocatalytic system enables the efficient removal of mixed pollutants by harnessing their synergistic effect, thereby overcoming the limitations of removing mixed pollutants with single water treatment technologies. Herein, fluorine-doped covalent triazine framework (F-CTF) was combined with Ga2O3-Bi4O7 heterojunction to obtain Ga2O3-Bi4O7/F-CTF (GaBi/CTF). F-CTF greatly facilitates the adsorption process and provides convenience for photocatalysis. Simultaneously, the excellent conductivity of F-CTF promoted the separation of photoinduced charge carriers in Ga2O3-Bi4O7. GaBi/CTF5 (5 is the mass percentage of F-CTF) showed excellent degradation performance, and the removal rates of PFOA and 2,4,6-TCP reached 93.0 % and 100.0 % within 90 min, respectively. Mechanistic analysis revealed that 2,4,6-TCP and PFOA were attacked by distinct active species because of the disparate characteristics. The presence of phenolic hydroxyl groups makes 2,4,6-TCP more vulnerable to superoxide radicals (·O2–) and hydroxyl radicals (·OH), whereas PFOA is oxidized by holes (h+). The coexistence of mixed pollutants with diverse characteristics enables optimal utilization of active species generated within photocatalytic system. Moreover, the good stability of GaBi/CTF5 provides a feasible solution for efficient treatment of mixed pollutants in textile wastewater.

Exploring Cu-doped graphitic carbon nitride for treatment of dye pollutants in textile wastewater: Benefits and limitations

This study introduces an innovative method utilizing Cu-doped graphitic carbon nitride (Cu-GCN) photocatalyst for the effective removal of dye pollutants such as methylene blue (D-MB) and Rhodamine B (D-RhB) from textile industry wastewater. The findings demonstrate that Cu-GCN achieves impressive degradation efficiency of 86.9 and 75.1 % for D-MB and D-RhB, respectively. Notably, the decomposition rate constants (k) exhibit an inverse relationship with pollutant concentrations. Specifically, the k value of D-MB and D-RhB using Cu-GCN increased from 0.010 to 0.023 min−1 and 0.009 to 0.022 min−1, respectively, with decreasing concentrations from 100 to 5 mg L−1. Besides, the decomposition efficiency of D-MB and D-RhB by Cu-GCN shows enhancements of 15.2 and 13.5 %, respectively, with a rise in solution pH from 5.0 to 9.0. Within 60 min of reaction time, Cu-GCN exhibits good decomposition efficiency of 69.1 % for D-MB and 55.3 % for D-RhB in textile wastewater samples. We also explore the comparative advantages and limitations of utilizing the photocatalysis process for the degradation of D-MB and D-RhB. This work offers valuable insights into the potential of Cu-GCN as a promising photocatalyst that can be further developed for effectively removing various pollutants from textile wastewater.

Emerging pollutants in textile wastewater: an ecotoxicological assessment focusing on surfactants.

Water and several chemicals, including dyestuffs, surfactants, acids, and salts, are required during textile dyeing processes. Surfactants are harmful to the aquatic environment and induce several negative biological effects in exposed biota. In this context, the present study aimed to assess acute effects of five surfactants, comprising anionic and nonionic classes, and other auxiliary products used in fiber dyeing processes to aquatic organisms Vibrio fischeri (bacteria) and Daphnia similis (cladocerans). The toxicities of binary surfactant mixtures containing the anionic surfactant dodecylbenzene sulfonate + nonionic fatty alcohol ethoxylate and dodecylbenzene sulfonate + nonionic alkylene oxide were also evaluated. Nonionic surfactants were more toxic than anionic compounds for both organisms. Acute nonionic toxicity ranged from 1.3mg/L (fatty alcohol ethoxylate surfactant) to 2.6mg/L (ethoxylate surfactant) for V. fischeri and from 1.9mg/L (alkylene oxide surfactant) to 12.5mg/L (alkyl aryl ethoxylated and aromatic sulfonate surfactant) for D. similis, while the anionic dodecylbenzene sulfonate EC50s were determined as 66.2mg/L and 19.7mg/L, respectively. Both mixtures were very toxic for the exposed organisms: the EC50 average in the anionic + fatty alcohol ethoxylate mixture was of 1.0mg/L ± 0.11 for V. fischeri and 4.09mg/L ± 0.69 for D. similis. While the anionic + alkylene oxide mixture, EC50 of 3.34mg/L for D. similis and 3.60mg/L for V. fischeri. These toxicity data suggested that the concentration addition was the best model to explain the action that is more likely to occur for mixture for the dodecylbenzene sulfonate and alkylene oxide mixtures in both organisms. Our findings also suggest that textile wastewater surfactants may interact and produce different responses in aquatic organisms, such as synergism and antagonism. Ecotoxicological assays provide relevant information concerning hazardous pollutants, which may then be adequately treated and suitably managed to reduce toxic loads, associated to suitable management plans.

Alkalophilic bacterial co-cultures for the remediation of toxic pollutants in textile wastewater

Alkalophilic bacterial co-cultures for the remediation of toxic pollutants in textile wastewater

Spectral change of dissolved organic matter after extracted by solid-phase extraction and its feasibility in predicting the acute toxicity of polar organic pollutants in textile wastewater.

Spectroscopic parameters can be used as proxies to effectively trace the occurrence of organic trace contaminants, but their suitability for predicting the toxicity of discharged industrial wastewater with similar spectra is still unknown. In this study, the organic contaminants in treated textile wastewater were subdivided and extracted by four commonly-used solid-phase extraction (SPE) cartridges, and the resulting spectral change and toxicity of textile effluent were analyzed and compared. After SPE, the spectra of the percolates from the four cartridges showed obvious differences with respect to the substances causing the spectral changes and being more readily adsorbed by the WAX cartridges. Non-target screening results showed source differences in organic micropollutants, which were one of the main contributors leading to their spectral properties and spectral variations after SPE in the effluents. Two fluorescence parameters (C1 and humic-like) identified by the excitation emission matrix-parallel factor analysis (EEM-PARAFAC) were closely correlated to the toxicity endpoints for Scenedesmus obliquus (inhibition ratios of cell growth and Chlorophyll-a synthesis), which can be applied to quantitatively predict the change of toxicity effect caused by polar organic pollutants. The results would provide novel insights into the spectral feature analysis and toxicity prediction of the residual DOM in industrial wastewater.

Application of Salvinia sps. in remediation of reactive mixed azo dyes and Cr (VI) - Its pathway elucidation

The emerging industrialization has resulted in the rapid growth of textile industries across the globe. The presence of xenobiotic pollutants in textile wastewater threatens the ecosystem. Applying different microbes (bacteria, fungi & algae) has paved the way for phytoremediation – the eco-friendly, cost-effective method. The present study focuses on the phytoremediation of reactive dyes - Reactive red, Reactive Brown & Reactive Black and Cr (VI) in synthetic textile wastewater using Salvinia sps. The mixed azo dyes of each 100 mg/L showed decolourization of 75 ± 0.5% and 82 ± 0.5% of removal of 20 mg/L of Cr (VI) after eight days of incubation in a phytoreactor setup. Chlorophyll analysis revealed the gradual decrease in the photosynthetic pigments during the remediation. The degraded metabolites were analyzed using FT-IR and showed the presence of aromatic amines on day zero, which were converted to aliphatic amines on day four. The GC-MS analysis revealed the disruption of –NN- bond, rupture of –CN- bond, scission of –N-N-bond, and loss of –SO3H from the Reactive Black dye leading to the formation of an intermediate p-Hydroxy phenylhydrazinyl. The rupture of Reactive red dye resulted in the formation of p-Hydrazinyl toluene sulphonic acid, Naphthyl amine −3,6-disulphonic acid and 8-Hydroxy Naphthyl amine −3,6-disulphonic acid. Decarboxylation, desulphonation, deoxygenation and deamination of Reactive Brown dye showed the presence of different metabolites and metabolic pathways were proposed for the reactive azo dyes which were phytoremediated.

Reuse of gamma-ray irradiated textile wastewater: implications on the growth of Capsicum frutescens plant

This investigation concentrates on the possibility of using gamma radiation for the decomposition of organic pollutants in textile wastewater and reuse as irrigation water. The wastewater sample was irradiated at four different absorbed doses of 3, 5, 8, and 10 kilo Gray (kGy). After irradiation at 8–10 kGy, physicochemical parameters, i.e., pH, turbidity, EC, total suspended solids (TSS) and total dissolved solids (TDS), have decreased sharply and approached to the expected value recommended by Department of Environment (DoE), Bangladesh. At 10 kGy absorbed dose, 59.0 % biological oxygen demand (BOD5) and 71.6 % chemical oxygen demand (COD) removal has been achieved, accelerating the enhancement in biodegradability index (BOD5/COD). Ammonium and total nitrogen have improved up to 87.0 % and 94.5 % after irradiation at 10 kGy doses. Subsequently, the treated textile wastewater samples were reused to grow Capsicum frutescens plants to inspect the fertility responses. When Capsicum plants were nourished by textile wastewater irradiated at 8–10 kGy, increased values were observed in the plant morphological parameters such as dry masses of the fruits (from 2.25 to 3.02 g), moisture content (from 91.35 to 92.62%), root length (from 13.21 to 16.56 cm), average plant height (from 2.42 to 4.07 cm/week), average number of leaves (from 14 to 16 nos./week), and total number of fruits (from 25 to 40 nos.) in comparison to those plants nourished by simply water and raw wastewater. The elemental analysis confirmed that negligible amounts of heavy metals were found in Capsicum fruits at higher absorbed doses. In contrast, helpful macro and micronutrients for plant production were raised to sufficient levels at 8–10 kGy, which can be the optimum doses for gamma irradiation to treat textile wastewater for maintaining sustainable water resources.

Wastewater treatment by adsorption with electrochemical regeneration using reactive brown 9 as adsorbate.

Textile industries are producing a huge amount of wastewater that contains harmful pollutants. The main pollutants in textile wastewater are dyes. In this work, adsorption and electrochemical regeneration of adsorbent Nyex 1000 have been studied using Reactive Brown 9 dye as adsorbate. Nyex 1000 successfully removed the dye from water, and then the adsorbent was regenerated electrochemically. The Regenerated adsorbent was retreated several times to check the change in regeneration efficiency. Regeneration efficiency remained more than 90% each time. To find more effective method of finding adsorbent capacity, kinetics were studied. It was found that Pseudo first order kinetic was more effective than pseudo second order kinetic.

Chromium bioremediation of batik industrial wastewater using a consortium of sulfate-reducing bacteria from forested wetland soil

Chromium pollutants in textile wastewater can be removed by bioremediation using sulfate-reducing bacteria (SRB) from forested wetland soil. Biostimulation of carbon sources in the form of molasses and a supporting material in the form of zeolite to trap bacteria and create biofilms can improve the ability of SRB to bioremediate chromium. The batch bioremediation technique was further examined by including molasses, a combination of molasses and zeolite, and SRB, which has been adapted to acclimatize wastewater that is diluted two times. Adaptive SRB aged 7 days, which had reached the exponential growth phase, showed optimal bioremediation activity when molasses and zeolite were added. Results of further observations of the consortium on continuous bioremediation with the same treatment showed decontamination of chromium efficiency that reached about 94%. In addition, pH values decreased efficiency at approximately 7.3 in 14 days of incubation. The biological oxygen demand, chemical oxygen demand, and sulfate concentrations also decreased at around 89%, 92%, and 91%, respectively. SRB immobilization with zeolite-induced biofilm formation was observed at 9 days, and it further increased at 14 days. SRB cells observed were attached to the surface of the zeolite, between cells connected to each other by extracellular polymeric substances. The mass of sulfur and chromium on the surface of the zeolite increased from the 9th and 14th days. Sulfur increased from 0.07% to 0.27%, whereas chromium increased from 0.21% to 0.84%. The increase in the percentage of the two elements on the zeolite surface indicated the decontamination of sulfate and chromium pollutants in wastewater.

Application of Activated Afzelia Africana and Acacia Albida Carbon for Removal of Pollutants in Textile Wastewater

Adsorption of contaminants in textile wastewater onto activated carbon derived from two wood species has been studied using batch-adsorption techniques. This study was carried out to examine the removal efficiency of the low-cost adsorbent (Afzelia africana) AFA and (Acacia albida) ACA for the removal of heavy metals and other organic contaminants from textile effluents. The influence of contact time and adsorbent dose kept constant on the adsorption process was also studied. Removal efficiency increased with increase in contact time. The two adsorbents had an average removal efficiency of 60% at 90mins contact time for Zn. The ACA had higher removal efficiency for chromium at all contact times than AFA except at 120mins contact time where there existed a slight difference in the removal efficiency between the two adsorbents. Removal efficiency of iron was high between 58.18- 70.52% and 72.75-75.86% for AFA and ACA carbon respectively. This showed that iron had high affinity to the adsorbents surface. It was observed that AFA exhibited highest removal efficiency for nitrate at all contact times as compared to ACA. Results indicated that the freely abundant, locally available, low-cost adsorbent derived from the two wood species could be treated as being economically viable for the removal of contaminants from textile effluents.

Application of electrocoagulation for textile wastewater treatment: A review

The increasing development of the textile industry is always followed by the amount of wastewater produced. The textile industry uses various types of synthetic dyes, and the amount of dyes is still high in its waste. The impact of the discharge of textile wastewater into the environment without rigorous treatment will damage the environment because the dense color of the waste can prevent light penetration for aquatic organisms. Also, various metals and other harmful chemicals can contaminate soil and water sources. One promising method for treating textile wastewater is electrocoagulation. Electrocoagulation can reduce pollutants in textile wastewater efficiently, cheaply, and reliably. In this review article, an explanation regarding the basis and techniques for processing textile wastewater by electrocoagulation will be presented. Various electrocoagulation operational parameters and their relation to the quality of textile wastewater treatment will be reviewed. In addition, problems and limitations of the application of electrocoagulation as a basis for the development of textile waste treatment in the future will be explained.

Treatment of Typical Organic Pollutants in Textile Wastewater by Direct Contact Membrane Distillation

Direct contact membrane distillation technology was considered as a promising and efficient technology for the treatment of textile wastewater. In this study, hydrophobic polytetrafluoroethylene and polyvinylidene fluoride membranes for the treatment of selected model compounds of textile wastewater (e.g., phenol, aniline, and sulfanilic acid) were explored comparatively in a bench-scale direct contact membrane distillation technology test unit. The effect of various operational parameters including temperature, flow rate, and concentration on the rejection performance was investigated systematically. The results indicated that an increased feed temperature and a faster cross flow velocity contributed positively to the direct contact membrane distillation performance. Limited rejection for phenol and aniline was witnessed, which can be due to their relatively lower boiling point. A > 99% of sulfanilic acid rejection was obtained under the same conditions. Furthermore, the polytetrafluoroethylene membrane always presented enhanced performance compared with the polyvinylidene fluoride samples. In brief, the direct contact membrane distillation process could be potentially used as a promising technique for the treatment of textile wastewater.

Decomposition of pollutants in textile wastewater during the Fenton process in the presence of iron nanocompounds

Decomposition of pollutants in textile wastewater during the Fenton process in the presence of iron nanocompounds

Decomposition of pollutants in textile wastewater during the Fenton process in the presence of iron nanocompounds

Decomposition of pollutants in textile wastewater during the Fenton process in the presence of iron nanocompounds

Biological aeration filter post-treating effluent from Fenton oxidation process of wastewater containing rhodamine B

In order to investigate the treatment of refractory organic pollutants in textile wastewater, Rhodamine B (RhB) was selected as a model pollutant to prepare the simulated wastewater. Aim to treat the effluent from Fenton oxidation process for wastewater containing RhB, biological aerated filter (BAF) was used as post-treatment process. The start-up process of the BAF reactor and the optimum operation conditions for the wastewater treatment process were investigated in this study. It was demonstrated by a series of bench-scale tests that the reactor could be successfully started up by exogenously inoculated activated sludge and gradual acclimation method. Operation condition experiments indicated that the BAF could achieve relatively high performance when gas–water ratio was 5–6, hydraulic retention time was controlled at 6–8 h and influent organic loading was within the range from 0.77 to 2.04 kgCOD/(m3 d).

The Applicability of an Advanced Oxidation Process for Textile Finishing Waste Streams & Fate of Persistent Organic Pollutants

The trend of sustainable use of available water resources encourages textile finishing enterprisesto implement efficient wastewater treatment technologies that enable water recycling, and not just it’sdischarging into the local wastewater treatment plants (WWTP). This paper presents the results obtainedfrom the H2O2/UV treatment of wastewater from Slovene textile finishing company. Laboratory scaledecolouration experiments were performed on the most representative wastewater samples, collected in three months period. In general 80 % decolouration and 86 % total organic carbon (TOC) reduction was achieved. On the other hand, the use of ultraviolet (UV) radiation to degrade and destroy organic pollutants in textile wastewater could lead to the formation of toxic dioxins and dioxin-like compounds, groups of persistent organic pollutants, especially due to the presence of halogenated compounds in textile finishing processes. For these reasons, textile wastewater samples were analysed for any content of dioxins before and after the treatment with H2O2/UV.

Decolorization and mineralization of reactive dyes by a photocatalytic process using ZnO and UV radiation

Reactive dyes are one of the major pollutants in textile wastewater and a concern because they are not easily degraded by conventional wastewater treatments. Heterogeneous photocatalysis has been considered an effective option for treating wastewater containing those dyes. This research work assesses the photocatalytic degradation of reactive dyes using UV irradiation and pure or impregnated ZnO. In addition to photocatalysis, separate photolysis and adsorption experiments were conducted but showed low efficiency. The dye degradation was monitored by UV-Vis spectroscopy and mineralization was determined by total organic carbon (TOC) analyses. Total color removal was achieved after 30 min of irradiation using pure ZnO. The Black 5 dye photocatalytic decolorization reaction followed first-order kinetics, while Yellow 145, Red 4 and Blue 21 dyes followed zero-order kinetics. TOC removals in the range of 70-80% were achieved after 240 min of individual photocatalytic treatment with ZnO. The performance of each photocatalyst was also compared when the four dyes were mixed together and the order of efficiency in the mineralization process was as follows: Fe/ZnO > ZnO > Co/ZnO. This result was explained by the crystal field theory.

Photo and Electrocatalytic Treatment of Textile Wastewater and Its Comparison

ABSTRACT: Electrochemical and photochemical techniques have been proved to be effective for the removal oforganic pollutants in textile wastewater. The present study deals with degradation of synthetic tex-tile effluents containing reactive dyes and assisting chemicals, using electro oxidation and photocatalytic treatment. The influence of various operating parameters such as dye concentration, cur-rent density, supporting electrolyte concentration and lamp intensity on TOC removal has beendetermined. From the present investigation it has been observed that nearly 70% of TOC removalhas been recorded for electrooxidation treatment with current density 5 mA/dm 2 , supporting elec-trolyte concentration of 3 g/L and in photocatalytic treatment with 250 V as optimum lamp intensitynearly 67% of TOC removal was observed. The result indicates that electro oxidation treatment ismore efficient than photocatalytic treatment for dye degradation.Keywords : TiO 2 /UV, Electro oxidation, Photocatalysis, Organic pollutant, Textile effluent

Application of expanded graphite/attapulgite composite materials as electrode for treatment of textile wastewater

Acid activation of attapulgite with hydrochloric acid was carried out to obtain greater specific surface area. The activated attapulgite was homogenized completely within an expanded graphite (EG) matrix for preparation of expanded graphite/attapulgite composite materials, which have excellent adsorption capacity and conductivity. The composite materials were used as electrode in treatment of textile wastewater, which was obtained from a local printing and dyeing mill, and contained various types of dyes, such as reactive blue and reactive yellow. The effects of initial pH value, electrolyte concentration, current density and electrolysis time on the treatment efficiency were investigated. Under optimum experimental conditions, the decolorization rate was close to 100%, and chemical oxygen demand (COD) was reduced from 443 g/L to 250 g/L. According to the results, EG/attapulgite composite seemed to be an excellent material for the degradation of organic pollutants in textile wastewater through adsorption and electrochemical oxidation. Also in the present work, scanning electron microscopy (SEM), infrared spectroscopy (IR), UV–vis, surface area and porosimetry systems were used to explain the relationship between the structure of EG/attapulgite and the possible interaction mechanism.