Arivazhagan Mahizhnan

Textile industrial wastewater contains high levels of chemical and nutrient pollutants, posing significant environmental challenges that conventional physicochemical treatments inadequately address, highlighting the need for eco-friendly biological alternatives utilizing native algal isolates. This study investigates the potential of native algal isolates for sustainable wastewater treatment. Algal strains were isolated from textile effluents and identified based on morphological characteristics and molecular sequencing as Cyanobacterium stanieri DSA01 (CS), Desertifilum salkalinema DSA02 (DS), and Ciimarium marinum DSA03 (CM). Three algal isolates were cultivated in 30 day batch experiments using two textile wastewater samples (TW1 and TW2) to evaluate treatment efficacy for chemical oxygen demand (COD) and key nutrients (e.g., nitrate, ammonia and phosphate). The maximum COD removal by DS was 88.49 ± 1.77% on day 5 in TW1 and 63.52 ± 1.27% on day 15 in TW2. DS consistently demonstrated nutrient removal efficiencies exceeding 50% in both TW1 and TW2. Biochemical analysis revealed a significant increase in protein content, indicating efficient nutrient utilization. The treated wastewater enhanced the shoot and root development of Vigna radiata seeds, confirming pollutant reduction and demonstrating potential for industrial reuse, agricultural irrigation, and aquatic ecosystem protection, thereby promoting sustainable wastewater management. This study confirms the applicability of native algal isolates as an effective and sustainable strategy for managing textile wastewater.

The textile industry plays a central role in economic development; however, the discharge of wastewater with diverse dyes poses higher risks to both ecosystems and human health. This study investigated the treatment of real‐time reactive dye–based textile industrial wastewater using a hybrid electrocoagulation (EC) and adsorption (AD) process, with algal‐derived activated carbon (AAC) as a novel adsorbent. AAC provides a sustainable and eco‐friendly option for enhancing treatment efficiency, along with the EC process, compared with the stand‐alone process. The present study focuses on finding out the optimal dosage of the adsorbent and time for the effective removal of COD and color. Maximum removal efficiency obtained for COD and color was 95.73% ± 1.91% and 58.70% ± 1.17%, respectively, with an optimal adsorbent dosage of 6 g/L and an optimum time of 50 min. Electrochemical studies revealed typical Tafel behavior for aluminum electrodes in wastewater. A negative corrosion potential indicates a propensity for anodic dissolution, crucial for coagulant generation, facilitating impurity removal in textile wastewater. Linear sweep voltammetry demonstrates that the aluminum electrode possesses the potential for both oxidation and reduction reactions, while the mesoporous structure and surface functional groups of the adsorbents together enhance the COD and color removal efficiency in the hybrid EC‐AD treatment process. The findings highlight the novelty and efficacy of the hybrid EC‐AD process in addressing the challenges associated with real‐time textile wastewater treatment.

Pollutants, including dyes and heavy metals from textile industrial discharge, adversely affect the surface and groundwater resources, and pose a severe risk to the living organisms in the ecosystem. Phycoremediation of wastewater is now an emerging trend, as it is colossally available, inexpensive, eco-friendly, and has many other benefits, with high removal efficiency for undesirable substances, when compared to conventional treatment methods. Algae have a good binding affinity toward nutrients and toxic compounds because of various functional groups on its cell surface by following the mechanisms such as biosorption, bioaccumulation, or alternate biodegradation pathway. Algae-based treatments generate bioenergy feedstock as sludge, mitigate CO₂, synthesize high-value-added products, and release oxygenated effluent. Algae when converted into activated carbon also show good potential against contaminants, because of its higher binding efficiency and surface area. This review provides an extensive analysis of different mechanisms involved in removal of undesirable and hazardous substances from textile wastewater using algae as green technology. It could be founded that both biosorption and biodegradation mechanisms were responsible for the removal of dye, organic, and inorganic pollutants. But for the heavy metals removal, biosorption results in higher removal efficiency. Overall, phycoremediation is a convenient technique for substantial conserving of energy demand, reducing greenhouse gas emissions, and removing pollutants. Graphical abstract