Role of biological and integrated bio-electrochemical techniques for degradation of textile dyes

Abstract

The development of first synthetic dye in 1865 has triggered the largescale production of more than 10,000 types of synthetic dyes globally. It is estimated that global production of these dyes is 1,000,000 tons annually (Tkaczyk et al., 2020). These dyes are widely utilized in various industries like food, paper, leather, tanning, cosmetic, textiles and pharmaceuticals. Despite that, textile industries contribute to 80% utilization of synthetic dyes out of all industries and generates approximately 70 billion tons of wastewater containing dyes annually (Lin et al., 2023). Therefore, water contamination and water scarcity issues have raised all over the globe which eventually has led to environmental and human health concerns. Currently, research in the treatment of dye containing wastewater has been mainly focussed on discoloration and mineralization of textile dyes. Conventional physiochemical and biological techniques have been studied in detail by the researchers for the degradation of textile dyes. Physio-chemical techniques, such as coagulation/flocculation, advanced oxidation, adsorption, and membrane filtration, have gained widespread acceptance. However, their reliance on costly chemicals and the need for managing sludge production and the formation of toxic by-products post-treatment pose significant challenges.