Synthetic Textile Wastewater Research Articles

Controlling pathogenic risks of water treatment biotechnologies at the source by genetic editing means.

Antimicrobial-resistant pathogens in the environment and wastewater treatment systems, many of which are also important pollutant degraders and are difficult to control by traditional disinfection approaches, have become an unprecedented treat to ecological security and human health. Here, we propose the adoption of genetic editing techniques as a highly targeted, efficient and simple tool to control the risks of environmental pathogens at the source. An 'all-in-one' plasmid system was constructed in Aeromonas hydrophila to accurately identify and selectively inactivate multiple key virulence factor genes and antibiotic resistance genes via base editing, enabling significantly suppressed bacterial virulence and resistance without impairing their normal phenotype and pollutant-degradation functions. Its safe application for bioaugmented treatment of synthetic textile wastewater was also demonstrated. This genetic-editing technique may offer a promising solution to control the health risks of environmental microorganisms via targeted gene inactivation, thereby facilitating safer application of water treatment biotechnologies.

Effect of operational time on the chemical oxygen demand performance of sequencing batch reactor treating disperse dye synthetic wastewater

This work examines the effect of operational time of 6 hours on the removal of disperse dye from synthetic textile wastewater. Experiments were conducted daily at fill, react, settle, draw, and idle phase at 1 h, 1 h, 2 h, 1 h, 1 h respectively. The results showed that the highest removal efficiency of COD reached 77 %. Short operational time resulted in low COD removal efficiencies of disperse dye. The findings also revealed that when applying optimum operational time, sequencing batch reactor will achieve the highest growth of the bacteria responsible for the degradation of COD. When operational time increases, degradation becomes the dominant removal mechanisms of COD.

Kinetics of COD and Dye Removal for Waste Water from Textile Industry

Abstract: Water pollution poses serious threats to both the environment and the organisms that depend on their environment for survival. Due to the toxicity from dyes in textile wastewater, there is a dire need for the development of innovative and efficient treatment technologies. In this study treatability studies, using a electrochemical treatment (ECT) method followed by activated carbon (AC) based adsorption. ECT method was studied extensively for the treatment of reactive black dye. Moreover, to understand the practical applicability of ECTs, the findings were optimized for treatment of synthetic textile wastewater (STW).

Treatment of textile wastewater containing mixed toxic azo dye and chromium (VI) BY haloalkaliphilic bacterial consortium

Scientific empowerment in this century created a positive and negative impact on the ecosystem's biotic and abiotic components. The current scenario of emerging recalcitrant pollutants in the environment is encountered using various remediation approaches are enforced and applied. The need for mineralization of the toxic pollutants to non - toxic forms accomplished the application of microbes (bacteria, fungi and algae) and plants individually or in a combined manner. The current research on the removal of pollutants from synthetic textile wastewater containing 1200 ppm concentration of mixed azo dyes –Reactive red (RR), Reactive Brown (RB) & Reactive Black (RBl) and 300 ppm Cr (VI) metal using haloalkaliphilic bacterial strains LBKVG1, LBKVG2, LBKVG3 & LBKVG4 in a Moving Bed Biofilm Reactor (MBBR), showed decolorization of 82 ± 0.5% of mixed azo dyes and degradation 56 ± 0.5% of Cr (VI) metal at 37 °C and pH 8.5 in the fifth day of the study. The isolated bacterial strains in the consortium were molecularly and morphologically characterized by 16SrRNA sequencing and SEM analysis. FT-IR and GC-MS analysis scrutinized the metabolites obtained. The findings suggest the degradation of hazardous pollutants even at higher concentrations and attempt to decolourize the mixed azo dyes simultaneously using the eco-friendly bacterial consortium.

Optimization of nutrient rich solution for direct fertigation using novel side stream anaerobic forward osmosis process to treat textile wastewater

The current study focused on the performance of a lab scale side stream anaerobic fertilizer drawn forward osmosis (An-FDFO) setup and optimization of nutrient rich solution to achieve sustainable water reuse from high strength synthetic textile wastewater. Three fertilizer draw solutes including Mono Ammonium Phosphate (MAP), Ammonium Sulphate (SOA) and Mono Potassium Phosphate (MKP) were blended in six different ratios with total molar concentration not exceeding 1 M. Among six blended draw solutions (DS), combination with high concentration of SOA have shown highest flux and combination with high concentration of MKP have shown highest reverse solute flux, while those with high concentration of MAP remain moderate both in flux and RSF. During long term runs, SOA: MKP (0.75: 0.25 M) showed longest filtration duration of 217 h in Run 1, with highest initial flux of 8.29 LMH and minimum dilution factor to achieve final nutrients concentration fit for direct fertigation, followed by Run 3 MAP: SOA: MKP (0.2: 0.6: 0.2 M) and then Run 2 MAP: MKP (0.75: 0.25). Moreover, deterioration of mixed liquor characteristics occurs in membrane tank due to high RSF. Similarly, the same inhibitory effect of reverse salt on biogas production was also assessed through Bio-Methane Potential experiments. However, Anaerobic Continuous Stirring Tank Reactor exhibited high performance efficacy, highlighting the importance of side stream submerged configuration in forward osmosis (FO) process.

Talaromyces cellulolyticus as a promising candidate for biofilm construction and treatment of textile wastewater

Screening of microorganisms with broad-spectrum adaptability to extreme acid–base conditions and highperformance is essential for the construction of high-efficient biochemical wastewater treatment system. Herein, an acid-tolerant fungus isolated from acid medium was successfully identified through micromorphological observation and molecular characterization. The isolated fungus matched well with the filamentous fungus and was eventually identified as Talaromyces cellulolyticus. Considering the wide-range adaptability to pH condition (2.0–9.0), high cellulase activity (11.25 U mL−1), ideal biofilm-forming property (17.87 mg cm−3) on the surface of ceramsites, high tolerance to metal ions, and potential adsorption performance for aniline dyes, T. cellulolyticus issuitable for the construction of biofilm treatment system and treatment of textile wastewater based on the investigation of the removal efficiency of chemical oxygen demand and chromaticity of the synthetic textile wastewater. A promising candidate filamentous fungus for the treatment of textile wastewater was provided.

Photocatalytic Treatment of Synthetic and Real Textile Wastewater Using Zinc Oxide Under the Action of Sunlight

Photocatalytic Treatment of Synthetic and Real Textile Wastewater Using Zinc Oxide Under the Action of Sunlight

Photocatalytic TiO2 incorporated PVDF-co-HFP UV-cleaning mixed matrix membranes for effective removal of dyes from synthetic wastewater system via membrane distillation

We report membranes with UV-cleaning properties by incorporating photocatalytic porous TiO2 sheets (PTS) (0–5 wt%) in the PVDF-co-HFP matrix. PTS were synthesized using controllable large-scale synthesis protocols by spray drying followed by calcination. These membranes were assessed for the removal of Congo red (CR) and methylene blue (MB) from synthetic textile industry wastewater system (CR: 100 mg l−1 + MB: 100 mg l−1 + 4% NaCl) via direct contact membrane distillation (DCMD) configuration and their UV-cleaning properties. The PTS were characterized by FE-SEM, TEM and different spectral techniques, while membranes were assessed by surface morphology (FE-SEM, AFM), thermal stability, hydrophobicity, permeate flux, and dye rejection performance. The surface morphology study of PTS revealed its micro-sized sheet with the porous surface. With increased PTS concentration in the membrane matrix, the flux and dye rejection of mixed matrix membranes improved. Suitably optimized PT3 (3 wt% PTS in PVDF-co-HFP matrix) membrane showed ~100% dye removal efficiency (MB and CR) and 6.1 kg m−2 h−1 vapour flux. Long run (5 days) DCMD experiments showed >91% flux recovery ratio (FRR) after UV-cleaning. This study suggests the suitability of the prepared membranes to treat textile wastewater and their UV-cleaning properties.

A study on removal of dye, COD, turbidity, and DO enhancement from synthetic textile wastewater by using natural adsorbent in RSM design: isothermal analysis

A study on removal of dye, COD, turbidity, and DO enhancement from synthetic textile wastewater by using natural adsorbent in RSM design: isothermal analysis

The influence of sulphate on the treatment of azo dye‐containing wastewater in an anaerobic‐microaerobic compartmentalized fixed‐bed bioreactor

AbstractA fixed bed reactor (FBR) comprised of an anaerobic zone (AZ) coupled to a micro‐aerated zone (MAZ) was used for the biological treatment of synthetic textile wastewater. The azo dye in the textile effluent is expected to be reduced to aromatic amines (decolouration) in AZ followed by biological degradation of the aromatic amines due to oxygen exposure in MAZ. We focused on assessing the effect of sulphate, a common component of textile wastewaters, on the degradation of the tetra‐azo dye Direct Black 22 (DB22). The influence of sulphide, a product of sulphate biological reduction, on the removal of aromatic amines, toxic by‐products of DB22 degradation, was also analyzed. The AZ and the MAZ were filled with expanded clay balls and polyurethane foam, respectively. The chemical oxygen demand and sulphate ratio (COD/SO4−2) in the feed started at 4.8 ± 0.2 and was later changed to 0.8 ± 0.1 by increasing the sulphate content. This change consequently increased DB22 removal efficiency from 38 ± 11% to 72 ± 6% in AZ and from 56 ± 7% to 75 ± 7% at MAZ, but also resulted in high sulphide concentration and reduced redox potential (ORP) at the MAZ inlet. However, the change negatively affected the degradation of aromatic amines in the MAZ. Aromatic amines were removed only at redox potential values higher than −228 mV and biogenic sulphide concentrations lower than 44 mg HS−/L.

Copper and chromium removal from synthetic textile wastewater using clay minerals and zeolite through the effect of pH

Copper and chromium removal from synthetic textile wastewater using clay minerals and zeolite through the effect of pH

Treatment of high‐strength synthetic textile wastewater through anaerobic osmotic membrane bioreactor and effect of sludge characteristics on flux

AbstractThe anaerobic osmotic membrane bioreactor (AnOMBR) system was evaluated for the treatment of high‐strength synthetic textile wastewater. The chemical oxygen demand (COD) concentration was above 3,000 mg/L and color above 1,300 Pt‐Co in the synthetic textile wastewater. The study was divided into six cycles of roughly nine days each. Mono ammonium phosphate with 1 M concentration was used as draw solution. Average COD and color removal efficiencies from anaerobic bioreactor were 57% ± 5% and 43.7% ± 6%, respectively; however, in OMBR permeate, these parameters were improved to 91% ± 4% and 91% ± 2%, respectively. After each cycle, membrane cleaning was performed using osmotic backwashing for 3 hours, which produced flux recovery values between 88% and 61% from cycle 2 to cycle 6, respectively. High mixing speed of the stirrer bar (600 rpm) in the bioreactor produced a greater shear force, causing a reduction in average sludge particle size from 10 to 3.5 μm. It increased the release of soluble microbial products and extra polymeric substances to cause an initial flux decline from 3.3 to 2.2 LMH from cycle 1 to cycle 6. The study proved AnOMBR as a promising technology for high‐strength synthetic textile wastewater treatment.

Highly efficient removal of methyl orange from aqueous media by amine functional cyclotriphosphazene submicrospheres as reusable column packing material

Polyphosphazenes have an important place in material science because they allow functional diversity to be realized easily. In this study, for the first time, synthesis of cyclomatrix-type poly-(cyclotriphosphazene-co-4-(aminomethyl)-1,8-octanediamine) (Phz-AO) particles including different surface features and dimensions have been reported using different stoichiometric ratios of hexachlorocyclotriphosphazene and 4-(aminomethyl)-1,8-octanediamine. The use of Phz-AO (1:2) submicroparticles with spherical form and average dimension of 647.82 ± 22.23 nm as an adsorbent was researched for methyl orange (MO) anionic azo dye. Submicrospheres had significant potential for adsorption of negative charged MO and maximum adsorption capacity of 1244.7 mg.g − 1. The submicrospheres displayed high adsorption potential at pH ≤6 conditions thanks to their surface amine groups. The maximum adsorption capacity in synthetic textile wastewater was 912.75 mg.g−1 as experimental. While the adsorption kinetics had the pseudo second order model, the most suitable model for adsorption was the Langmuir isotherm. The thermodynamic parameters for MO adsorption with submicrospheres were 10.02 ± 1.81 kj.mol−1 for ΔH°, 61.08 ± 5.74 j.mol−1.K−1 for ΔS° and ΔG° (kj.mol−1)<0. In light of all data obtained, the Phz-AO (1:2) submicrospheres which can be easily prepared with a single-step reaction are expected to be a remarkable member of the super adsorbent material family.

Treatment of Synthetic Textile Wastewater using Enhanced Adsorption onto Calcium Alginate Polymer in the Presence of Ultrasonic Waves

Treatment of Synthetic Textile Wastewater using Enhanced Adsorption onto Calcium Alginate Polymer in the Presence of Ultrasonic Waves

Heterogeneous activation of peroxymonosulfate with Fe3O4 magnetic nanoparticles for degradation of Reactive Black 5: Batch and column study

In the present study, magnetite nanoparticles (Fe3O4) were used to activate peroxymonosulfate (PMS) in the degradation of Reactive Black 5 (RB5) from aqueous solutions. 94.86% of RB5 was degraded using Fe3O4 dosage of 250 mg L−1, PMS of 2 mM at pH of 7 after 60 min. The RB5 degradation rate was improved with temperature, and the activation energy was obtained to be 13.36 kJ mol−1. The presence of chloride, carbonate, nitrate, and bicarbonate in the solution reduced the rate of RB5 degradation due to the scavenging effect and the production of reactive species with low oxidation potential. Fe3O4 exhibited excellent stability for 240 min in a column reactor. The scavenging experiments emphasized that both SO4•- and •OH play an important role in the tests; however, SO4•- was the dominant species for RB5 degradation. The possible mechanism of PMS decomposition into reactive species by Fe3O4 was proposed. The column reactor showed a degradation efficiency of 95.65%, 80%, and 50% for RB5 in the synthetic sample, surface water, and textile wastewater, respectively. Toxicity was assessed by culturing Escherichia coli (E. coli) under the optimal condition. Five RB5 degradation products were identified by gas chromatography-mass spectrometry (GC-MS), and SO42-, NH4+, NO3-, CO2 and H2O were produced as the final mineralized products in the Fe3O4/PMS system. Comparative experiments have shown that the Fe3O4 catalyst has high efficiency in PMS activation and RB5 degradation; however, the presence of ultrasound, heat, and ultraviolet in the catalytic system can be beneficial to increase the degradation rate during fewer reaction times.

Comparative investigation of RSM and ANN for multi-response modeling and optimization studies of derived chitosan from Archachatina marginata shell

The design of this paper was to investigate comparatively the optimization techniques of response surface methodology (RSM) and artificial neural network (ANN) when applied to the conditions for chitosan production from Archachatina marginata shell and the % removal of methylene blue, MB, from synthetic textile wastewater. The proposed RSM and ANN models are optimized using genetic algorithm (GA). The optimum conditions for the extraction processes of chitosan and % removal of MB are determined and the derived chitosan at optimized conditions is characterized using analytical techniques. The ANN portrays better modeling abilities than RSM for the responses. The predicted values of % yield of chitosan, % DD and % removal of MB are obtained as 51.56, 98.68 and 94.71 respectively using the RSM-GA technique while the ANN-GA technique predicted 45.32%, 91.96% and 95.96% respectively. The experimental values of the responses are in excellent agreement with the ANN-GA predicted values with % errors being 1.8, 1.2 and 1.19 respectively. Hence, the conditions of chitosan production from Archachatina marginata shell and its bioremediation capacity of synthetic wastewater from textile industry can be adequately and accurately optimized and modeled using ANN-GA for routine seafood applications and treatment of industrial wastewater effluents.

Evaluation of combined anaerobic membrane bioreactor and downflow hanging sponge reactor for treatment of synthetic textile wastewater

Various toxic chemicals in textile wastewater can cause serious problems for the ecosystem and human health if it is discharged without proper treatment. In this study, the performance of textile wastewater treatment using an anaerobic membrane bioreactor (AnMBR) combined with a downflow hanging sponge (DHS) reactor is evaluated. An AnMBR with a working volume of 5 L and a third-generation DHS with a working volume of 0.5 L is used to treat synthetic textile wastewater containing Reactive Black 5 azo dye. The experiment is performed under ambient conditions using AnMBR hydraulic retention times (HRTs) of 12 and 24 h, DHS HRTs of 1.4 and 2.8 h, and membrane fluxes of 2.65 and 5.21 LMH. The AnMBR-DHS combination significantly reduces the biochemical oxygen demand, chemical oxygen demand, and color of the synthetic textile wastewater by approximately 97.3 ± 1.8%, 94.4 ± 4.8%, and 95.0 ± 1.6%, respectively. Most of the reduction occurs in the AnMBR. The HRT and membrane flux do not significantly affect the performance of the AnMBR-DHS system. The microbial community in the AnMBR is dominated by the phyla Euryarchaeota, Caldiserica, and Proteobacteria, whereas that in the DHS is dominated by Proteobacteria. Some of the genera found in the AnMBR can reportedly reduce azo dyes, whereas some of those found in the DHS can reportedly degrade sulfonated aromatic amines.

Anaerobic structured‐bed reactor for azo dye decolorization in the presence of sulfate ions

AbstractBACKGROUNDTextile wastewater is known for its polluting potential and toxicity. Biological, affordable treatments are especially desirable in developing countries to fulfill legal and ecological demands during its treatment.RESULTSThe performance of an anaerobic structured‐bed reactor (AnSTBR) treating synthetic textile wastewater containing Direct Black 22 azo dye (DB22; 0.06 mmol L–1) and sulfate ions (200 mg L−1) was evaluated. The reactor hydraulic retention time (HRT) was 24 h and ethanol was used as the electron donor (1000 mgCOD L−1). The AnSTBR achieved an average decolorization efficiency of 68 ± 5%, chemical oxygen demand (COD) efficiency of 77.7 ± 9.2% and sulfate removal of 77.3 ± 5.2%. Toxicity tests showed lower toxicity of the treated effluent to Ceriodaphnia dubia. Despite that, the AnSTBR effluent was still highly toxic to mammalian cells. The metabarcoding technique of the 16S rRNA gene sequencing revealed a consistent community of sulfate‐reducing and azo‐degrading bacteria.CONCLUSIONMetagenomic data revealed a promising development of the inoculum in the AnSTB structure. The AnSTB reactor configuration may be a promising alternative for DB22 dye removal from textile wastewater containing sulfate. © 2021 Society of Chemical Industry

A positively charged loose nanofiltration membrane fabricated through complexing of alginate and polyethyleneimine with metal ions on the polyamideimide support for dye desalination

Abstract Nowadays, loose nanofiltration (NF) membranes are preferred for dye desalination to achieve high dye/salt selectivity and enable filtration at low operating pressure. However, current fabrication techniques require rigorous reaction conditions and long preparation times. Herein, we used the chelating ability of the polyethyleneimine (PEI) and alginate with the metal ions to fabricate loose NF membranes via a facile approach. The positively charged polyamide imide (PAI)/PEI support was used to build the assembly. Direct attachment of Zn or Fe ions to the PEI chains did not result in a stable complex in the presence of a high salt concentration (1000 ppm NaCl). On the other hand, alginate coated on the support allowed building permanent assemblies after crosslinked with Fe3+ and Zn2+ transition metal ions. The PAI/PEI-Alg-Fe3+ membrane exhibited the highest permeability, excellent antifouling behaviour upon exposure to synthetic textile wastewater, and maintained long-term stability under static and dynamic conditions. Also, the same membrane rejected dyes and coloured substances in real wastewater sample during 72 h continuous filtration. With alginate metal complex formation on a suitable support, a scalable loose NF membrane was manufactured, demonstrating improved throughput value compared to current NF membranes.

CoFe2O4@Methylcelloluse as a New Magnetic Nano Biocomposite for Sonocatalytic Degradation of Reactive Blue 19

Reactive Blue 19 (RB19) removal from synthetic textile wastewater was investigated by using a CoFe2O4@methylcellulose (MC) activated with peroxymonosulfate (PMS) and the ultrasound process. CoFe2O4@MC as a new magnetic nano-biocomposite was prepared using a convenient and rapid microwave-assisted technique in presence of MC as a green biopolymer, and characterized by FESEM, EDS, Mapping, TEM, FTIR, XRD, TGA, VSM, and BET techniques. Then, the effective parameters including pH (4–10), reaction time (0–30 min), CoFe2O4@MC (0.2–1 g/L), and PMS concentration (0.5–10 mM) in the sonocatalytic degradation of RB19 were investigated. The maximum removal efficiency of RB19 was achieved as 97% for synthetic wastewater under the optimal conditions of pH 4, CoFe2O4@MC dosage (0.6 g/L), reaction time = 30 min, and PMS (5 mM) in the presence of ultrasonic waves (60 kHz) at the ambient room temperature of 22 °C. The CoFe2O4@MC catalyst was simply isolated using a magnet and recycled with no remarkable loss of catalytic activity following usage in four runs. The results showed that the CoFe2O4@MC sonocatalysis process is practical, and effective for degrading complex and resistant dyes such as RB19.