Search Results (162)

Ozonation and ozone-based advanced oxidation processes, including ozone/hydrogen peroxide and ozone/ultraviolet irradiation, have been extensively studied for their efficacy in treating wastewater across various industries. While sectors such as pulp and paper, textile, food and beverage, microelectronics, and municipal wastewater have successfully implemented ozone at full scale, others have yet to fully embrace these technologies’ effectiveness. This review article examines recent publications from the past two decades, exploring novel applications of ozone-based technologies in treating wastewater from diverse sectors, including food and beverage, agriculture, aquaculture, textile, pulp and paper, oil and gas, medical and pharmaceutical manufacturing, pesticides, cosmetics, cigarettes, latex, cork manufacturing, semiconductors, and electroplating industries. The review underscores ozone’s broad applicability in degrading recalcitrant synthetic and natural organics, thereby reducing toxicity and enhancing biodegradability in industrial effluents. Additionally, ozone-based treatments prove highly effective in disinfecting pathogenic microorganisms present in these effluents. Continued research and application of these ozonation and ozone-based advanced oxidation processes hold promise for addressing environmental challenges and advancing sustainable wastewater management practices globally. Full article

Industrial wastewater management remains a critical barrier to achieving Sustainable Development Goal 6 (SDG 6) in many developing countries, where regulatory frameworks exist but affordable and scalable treatment solutions are lacking. In Pakistan, the textile sector is a leading polluter, with untreated effluents routinely discharged into rivers and agricultural lands despite stringent National Environmental Quality Standards (NEQS). This study presents a pilot-scale case from Faisalabad’s Khurrianwala industrial zone, where a decentralized, nature-based bioreactor was piloted to bridge the gap between policy and practice. The system integrates four treatment stages—anaerobic digestion (AD), floating treatment wetland (FTW), constructed wetland (CW), and sand filtration (SF)—and was further intensified via nutrient amendment, aeration, and bioaugmentation with three locally isolated bacterial strains (Acinetobacter junii NT-15, Pseudomonas indoloxydans NT-38, and Rhodococcus sp. NT-39). The fully intensified configuration achieved substantial reductions in total dissolved solids (TDS) (46%), total suspended solids (TSS) (51%), chemical oxygen demand (COD) (91%), biochemical oxygen demand (BOD) (94%), nutrients, nitrogen (N), and phosphorus (P) (86%), sulfate (26%), and chloride (41%). It also removed 95% iron (Fe), 87% cadmium (Cd), 57% lead (Pb), and 50% copper (Cu) from the effluent. The bacterial inoculants persist in the system and colonize the plant roots, contributing to stable bioremediation. The treated effluent met the national environmental quality standards (NEQS) discharge limits, confirming the system’s regulatory and ecological viability. This case study demonstrates how nature-based systems, when scientifically intensified, can deliver high-performance wastewater treatment in industrial zones with limited infrastructure—offering a replicable model for sustainable, SDG-aligned pollution control in the Global South. Full article

This study presents the development of a textile-based cascade filter for the removal of microplastics from an industrial laundry effluent. The cascade microfilter consists of three stages of 3D textile sandwich composite filter media, which have successively finer pores and are aimed at filtering microplastic particles down to 1.5 µm. Polypropylene fabrics with pore sizes of 100, 50 and 20 µm and 3D warp-knitted fabrics with high porosity (96%) were used. Filtration tests were carried out with polyethylene model microplastic particles at a concentration of 167 mg/L. To regenerate the filter and restore its filtration performance, backwashing with filtered water and compressed air was applied. Field trials at an industrial laundry facility and a municipal wastewater treatment plant confirmed high removal efficiencies. The 3D textile sandwich structure promotes filter cake formation, allowing extended backwash intervals and the effective recovery of filtration capacity between 89.7% and 98.5%. The innovative use of 3D textile composites enables a high level of microplastic removal while extending the filter media lifetime. This makes a significant contribution to the reduction in microplastic emissions in the aquatic environment. The system is scalable, space and cost efficient and adaptable to various industrial applications and is thus a promising solution for advanced wastewater treatment. Full article

Textile dyeing wastewater is one of the most challenging industrial effluents to treat due to its high concentrations of persistent organic compounds and nitrogenous substances. Conventional treatment methods often fall short in achieving both sufficient removal efficiency and environmental safety. In this study, we aimed to remove the total nitrogen (T-N) and total organic carbon (TOC) of dyeing wastewater from an industrial complex in D City, Korea, by applying bipolar and packed bipolar electrolysis using aluminum (Al) electrodes and activated carbon (AC). The system was operated for 60 min under varying conditions of applied voltage (5–15 V), electrolyte type and concentration (non-addition, NaCl 5 mM, NaCl 10 mM, Na₂SO₄ 5 mM, Na₂SO₄ 10 mM), and AC packing amount (non-addition or 100 g/L). The highest T-N and TOC removal efficiencies were observed at 15 V, reaching 69.53% and 63.68%, respectively. Electrolyte addition significantly improved initial treatment performance, with NaCl 10 mM showing the best results. However, Al leaching also increased, from 549.83 mg/L (non-addition) to 623.06 mg/L (NaCl 10 mM). When AC was used without electrolysis (control experiment), the T-N and TOC removal efficiencies were limited to 30.24% and 29.86%, respectively. In contrast, AC packing combined with 15 V electrolysis under non-addition achieved 86.04% T-N and 77.98% TOC removal, while also reducing Al leaching by 40.12%. These results suggested that electrochemical treatment with AC packing under non-addition conditions offers the best balance between high treatment efficiency and low environmental impact. These findings demonstrate that the synergistic use of packed activated carbon and electrochemical treatment under additive-free conditions can overcome the limitations of conventional methods. This study contributes to the development of more sustainable and effective technologies for treating high-strength industrial wastewater. Full article

The environmental impacts of industrial processes have increased the demand for sustainable alternatives in wastewater treatment. Conventional chemical coagulants, though widely used, can generate toxic residues and pose environmental and health risks. Biocoagulants, derived from natural and renewable sources, offer a biodegradable and eco-friendly alternative. This review explores their potential to replace synthetic coagulants by analyzing their origins, mechanisms of action, and applications. A total of 15 studies published between 2020 and 2025 were analyzed, all focused on industrial wastewater. These studies demonstrated that biocoagulants can achieve similar, or the superior, removal of turbidity (>67%), solids (>83%), and heavy metals in effluents from food, textile, metallurgical, and paper industries. While raw materials are often inexpensive, processing costs may increase production expenses. However, life cycle assessments suggest long-term advantages due to reduced sludge and environmental impact. A textile industry case study showed a 25% sludge reduction and improved biodegradability using a plant-based biocoagulant compared to aluminum sulfate. Transforming this waste into inputs for wastewater treatment not only reduces negative impacts from disposal but also promotes integrated environmental management aligned with circular economy and cleaner production principles. The review concludes that biocoagulants constitute a viable and sustainable alternative for industrial wastewater treatment. Full article

The periodate/hydrogen peroxide (PI/H₂O₂) system is a recently developed advanced oxidation process (AOP) characterized by its rapid reaction kinetics, making it highly suitable for continuous-flow applications compared to conventional batch systems. Despite its potential, no prior studies have investigated its performance under flowing conditions. This work presents the first application of the PI/H₂O₂ process in a tubular microreactor, a promising technology for enhancing mass transfer and process efficiency. The degradation of textile dyes (specifically Basic Yellow 28 (BY28)) was systematically evaluated under various operating conditions, including reactant concentrations, flow rates, reactor length, and temperature. The results demonstrated that higher H₂O₂ flow rates, increased PI dosages, and moderate dye concentrations (25 µM) significantly improved degradation efficiency, achieving complete mineralization at 2 mM PI and H₂O₂ flow rates of 80–120 µL/s. Conversely, elevated temperatures negatively impacted the process performance. The influence of organic and inorganic constituents was also examined, revealing that surfactants (SDS, Triton X-100, Tween 20, and Tween 80) and organic compounds (sucrose and glucose) acted as strong hydroxyl radical scavengers, substantially inhibiting dye oxidation—particularly at higher concentrations, where nearly complete suppression was observed. Furthermore, the impact of water quality was assessed using different real matrices, including tap water, seawater, river water, and secondary effluents from a municipal wastewater treatment plant (SEWWTP). While tap water exhibited minimal inhibition, river water and SEWWTP significantly reduced process efficiency due to their high organic content competing with reactive oxygen species (ROS). Despite its high salt content, seawater remained a viable medium for dye degradation, suggesting that further optimization could enhance process performance in saline environments. Overall, this study highlights the feasibility of the PI/H₂O₂ process in continuous-flow microreactors and underscores the importance of considering competing organic and inorganic constituents in real wastewater applications. The findings provide valuable insights for optimizing AOPs in industrial and municipal wastewater treatment systems. Full article

Humans are in constant contact with clothing and textiles throughout their lives, which can expose them to chemicals present in these materials. Chemicals used in fiber production and in material processing can be absorbed through the skin, ingested, or inhaled, causing allergic reactions. Advancements in modern textiles have made them more versatile and functional for a variety of applications, resulting in the use of more chemicals. Regarding the textile industry, several studies have focused on the environmental impact of its effluents and dyes, and, more recently, several studies have focused on textile waste impact in general. Nevertheless, few studies have been carried out on human cytotoxicity, and very little is known about the dangers of long-term use of textiles. The aim of this work was to review the literature to understand what has been done in the field of textile cytotoxicity. In addition, this work also highlights the existing gap regarding regulation and standardized tests for the analysis of everyday clothing. There is an urgent need to establish regulations and standardize testing protocols to assess the potential cytotoxic effects that may arise from finished textile products before they are marketed, in order to guarantee consumer safety. Full article

Microbial enzymes have revolutionised the textile industry by replacing harmful chemicals with eco-friendly alternatives, enhancing processes such as desizing, scouring, dyeing, finishing, and promoting water conservation while reducing pollution. This review explores the role of enzymes like amylases, pectinases, cellulases, catalases, laccases, and peroxidases in sustainable textile processing, focusing on their ability to mitigate environmental pollution from textile effluents. The review also examines the types and characteristics of hazardous textile waste and evaluates traditional waste treatment methods, highlighting sustainable alternatives such as microbial enzyme treatments for effluent treatment. Recent advancements in recombinant enzyme technology, including enzyme engineering and immobilisation techniques to enhance stability, reusability, and catalytic performance, are also explored. Additionally, the potential of extremozymes in textile processing and effluent treatment is explored, emphasising their stability under harsh industrial conditions. Strategies for reducing textile waste through enzyme-based processes are presented, focusing on principles of the circular economy. The review also addresses challenges such as scalability, cost, and process optimisation, while proposing potential solutions and outlining future directions for the widespread adoption of microbial enzymes in sustainable textile production and waste management. This review underscores the transformative potential of microbial enzymes in achieving greener textile manufacturing practices. Full article

Effective wastewater management is a critical environmental challenge, particularly in industrial regions like Faisalabad, where untreated textile effluents contribute to severe water pollution. This study evaluates the potential of phytoremediation using floating aquatic plants—Eichhornia crassipes (water hyacinth), Pistia stratiotes (water lettuce), and Lemna minor (common duckweed)—for the treatment of industrial textile wastewater. A controlled laboratory-scale experiment was conducted to assess pollutant removal efficiency over a 10-day retention period. The initial effluent concentrations of key parameters were measured before treatment to establish baseline conditions. The results demonstrated that Eichhornia crassipes exhibited the highest removal efficiency, achieving reductions of 36.12% (TDS), 36.14% (EC), 36.30% (salinity), 6.12% (pH), 34.30% (total hardness), and 44.52% (chloride). Furthermore, Pistia stratiotes and Lemna minor were particularly effective in removing nitrate (99.76%), ammonium (52.11%), and sodium adsorption ratio (46.29%), indicating species-specific phytoremediation potential. These findings highlight the viability of a low-cost, eco-friendly, and sustainable nature-based solution for wastewater treatment in industrial clusters, offering a practical alternative to conventional treatment technologies. Full article

The use of indigo carmine dye in the textile industry, particularly in denim production, presents a significant sustainability challenge due to the large amounts of wastewater generated by this process, since this fabric is one of the most produced around the world. In order to face challenges like this, effluent treatment using polymeric materials has become an area of intense research. In this study, we developed an eco-friendly hydrogel based on oligoglycerol-malic acid polyester crosslinked with citric acid, which was applied to adsorb indigo carmine. The properties of the hydrogel and its precursors were analyzed using spectroscopic, thermal, and morphologic techniques. The hydrogel demonstrated water uptake capacity up to 187% of its own mass and adsorbed approximately 73% of the dye after 24 h of contact. Tests were conducted in the presence of sodium chloride and indicated that the presence of salt impairs the adsorption process. Additionally, the adsorption kinetics and isotherms were evaluated and demonstrated that the adsorption followed a pseudo-second-order model, indicating a chemisorption process, and a Langmuir isotherm, consistent with a monolayer adsorption. These results emphasize the potential of this hydrogel for removing dye and its application in textile industry wastewater treatment, aiming to minimize environmental impacts. Full article

The dyeing industry plays a substantial role in environmental pollution, primarily through the release of wastewater that contains a variety of chemicals into aquatic ecosystems. Synthetic dyes play a crucial role in numerous sectors, including textiles, tanning, food production and pharmaceuticals. However, the effluents generated by industries that utilize these dyes are regarded as detrimental to both the environment and human health. Additionally, wastewater may include a range of chemical additives utilized during the dyeing process, including fixing agents, surfactants and pH adjusters. Various techniques for dye remediation have been extensively studied. Nevertheless, effective and economically viable methods for dye removal have yet to be fully developed. This paper emphasizes and provides an overview of the recent literature concerning the application of the most commonly accessible biogenic materials in the context of dye removal by the adsorption process. Various biogenic adsorbents sourced from plants, algae, microorganisms and biopolymers contain bioactive compounds that interact with the functional groups of dyes, leading to their attachment to the sorbent. By mechanical, thermal and chemical modifications of these materials, their adsorption capabilities could be increased. Full article

Wastewater treatment plants (WWTPs) play a crucial role in mitigating microplastic (MP) release to the environment. In this paper, a WWTP of a textile manufacturing plant in Guangdong, China, was investigated to identify MP characteristics and the effectiveness of wastewater treatment within the plant. Laser Direct Infrared (LDIR) and Liquid Chromatography with Mass Spectrometry (LC-MS/MS) were applied to quantify both the number and the mass of the microplastics in the effluent of the textile manufacturing plant where most of the wastewater were from three printing and dyeing lines. The study further investigated the MP removal efficiency of each wastewater treatment process of the industry-owned WWTP and analysed the removal mechanism of each step, highlighting limitations in detecting and eliminating MPs. It is observed that (1) the results from LDIR and LC-MS/MS can be complementary to each other; (2) the MP concentration in the influent was 1730 n/L by number and 13.52 µg/L by mass; (3) the total removal efficiency of the WWTP were 99% by the number of MPs and 67.7% by the mass of MPs; (4) nine types of polymers have been identified in the influent, of which Polyamide (PA) was dominating; (5) hydrolysis acidification removed PA most; (6) aerobic tank, sand filter, and biological aerated filter (BAF) showed low removal efficiency; (7) coagulation and sedimentation tank had the highest removal efficiency to PET than any other processes. Full article

Industrial wastewater treatment is essential to mitigate pollution and address global water scarcity. In this study, an activated carbon/copper (II) complex (AC/CuL) composite was obtained for enhanced removal of organic compounds by coupling adsorption and oxidation. Tests were performed using Drimaren Red X-6BN (DRX-6BN) and oily effluent at pH~6.0. Tests to obtain the adsorption kinetics of DRX-6BN (20 mg/L) were performed at 25 °C and using an amount of 0.42 g/200 mL of solution. The data were well fitted by several models, suggesting a complex adsorption process; however, the best fit was achieved by the pseudo-second-order (PSO) model (R² = 0.9996). The adsorption data best fit the Freundlich model. The addition of hydrogen peroxide to the system reduced the need for adsorbent, removing approximately 100% of the chemical oxygen demand (COD) from the emulsion in 120 min using only 0.04 g of AC/CuL. The material exhibited high storage stability and maintained its effectiveness in removing oil and grease (O&G) content and COD for at least 12 months. These results indicate that AC/CuL is promising for the removal of complex organic compounds, such as that from the textile and petroleum industries. These findings offer a sustainable, economical, and safe approach for wastewater treatment. Full article

The objective of this study is to utilize a simulation employing advanced oxidation processes (AOPs) from photodegradation to examine the treatment of textile effluents. The selection of textile effluents as the material to be degraded is justified by the significant volume of water containing dyes, such as methylene blue (MB), generated daily by the textile industry. Often, this water is discarded without undergoing effective treatment. The purification of textile effluents would enable the reuse of water within the textile production cycle, thereby promoting sustainability. This study focuses on AOPs, which are extensively utilized in photocatalytic processes. The catalytic precursor material consists of two types of clay: a commercial clay and a natural clay. The natural clay is pillared with Al and impregnated with Ce, while the commercial clay is also pillared with Al and impregnated with Ce. Both clays are also pillared with a mixed pillar of Al and Ce. This results in three comparable materials. These clays are characterized by the presence of montmorillonite as their predominant mineral component. The selected clays were commercial bentonite and natural clay (FCN). Photocatalytic performance validation tests were conducted using UV-Vis spectroscopy. Material characterization methods included crystallographic analysis (by X-Ray diffraction (XRD)), chemical composition (by X-Ray fluorescence (XRF)), morphological studies (by scanning electron microscopy (SEM)) and textural property analysis (by N₂ adsorption). The outcomes of these investigations offer signification insights into the potential applications of these materials in the treatment of textile effluents and the development of more sustainable processes within the textile industry. Furthermore, the results contribute to the advancement of photocatalytic material design. Full article

Globalization has increased production in various industries, including textiles, food, and pharmaceuticals. These industries employ different dyes in production, leading to undesired discharge, which conventional treatment fails to remove from the water. The present study aims to synthesize, characterize, and use different pure catalysts (TiO₂ and Zn₂SnO₄) and their compounds doped with CoFe₂O₄ together with ozone (O₃) for the degradation of the azo dye yellow tartrazine (TZ), evaluating the process. For this characterization, N₂ porosimeter, zeta potential, X-ray diffraction, SEM-EDS, and diffuse reflectance spectra were used. Specific surface areas (m² g⁻¹) of 109, 106, 65, and 83 were used for TiO₂, CoFe₂O₄/TiO₂, Zn₂SnO₄, and CoFe₂O₄/Zn₂SnO₄, respectively. Both compounds are characterized as nanocatalysts as they have a band gap of 2.75 and 2.83 eV and average particle size of 98 and 85 nm for CoFe₂O₄/TiO₂ and Zn₂SnO₄, respectively. We employed a reactional model, which was able to describe the catalytic ozonation for all cases, with a low R² of 0.9731. The combination of processes increased TZ degradation from 57% to 74% compared to O₃ alone, achieving a maximum degradation of 98.5% within 50 min of catalysis at a low ozone flow rate. This highlights the potential of the produced catalysts for energy-efficient effluent treatment. Full article