A sustainable approach for remediation of Reactive dye contaminated water

Abstract

The treatment of effluent from textile industries that contains synthetic dyes poses a significant environmental issue due to its toxic effects. Addressing the effluent containing reactive dyes is crucial because these dyes are mainly used for dyeing cotton, which is the most commonly used fiber. They also exhibit a low degree of fixation to fibers and resist conventional treatment methods. Reactive dyeing demands substantial water during processing, contributing to water scarcity, and if left untreated, results in the build-up of persistent organic pollutants in the soil. The primary challenges associated with physical and chemical dye treatment methods include high costs and the need for strict reaction conditions. In contrast, biological treatment methods are more affordable and environmentally safe. Microbial and enzymatic systems can be employed to biodegrade dyes. However, the microbial cultures capable of degrading reactive dyes must be transformed into a format that can be easily and safely handled at effluent treatment plants (ETP), even by individuals with minimal training. Consequently, this research developed a formulation that includes a microbial consortium of Enterobacter hormaechei, Neobacillus niacini, and Enterobacter ludwigii for the treatment of Reactive Brown HER and Navy Blue HER dyes. Three treatment approaches were studied: T1, which used the microbial formulation; T2, which involved ozonation; and T3, a combination of the microbial formulation and ozonation. The percentage decolorization tests showed that using the microbial formulation for two days, followed by ozonation, achieved a decolorization of 98.54% for Reactive Brown HER and 97.92% for Navy Blue HER dyes.