Impacts on color properties of textile fabric following repetitive utilization of electro-coagulated dyeing wastewater

In the textile industry, the process of washing off dyes requires a substantial amount of water, leading to the generation of heavily polluted wastewater. This study assessed the viability of electrocoagulation (EC) treatment for degradation of reactive orange 84 dye in wash-off liquor and its repetitive utilization in the same process by using a laboratory-scale experimental setup. Optimal operational factors, including electrolysis time, pH and applied current were determined through experimentation, resulting in a maximum color removal efficiency of 99 %. This efficiency was achieved at reaction time of 10 min, pH 7.5 and a current 1.0 A. Evaluation of fabric quality, considering color difference and wash fastness properties, indicated that the color difference values for dyed fabric samples over five repetitive reuses fell within an industrially acceptable range (ΔEcmc < 1). Wash fastness properties remained comparable to conventionally washed fabric samples, with negligible differences in color strength (K/S) values. Despite an escalation in pH, COD, TDS, and turbidity level after each reuse, the overall quality of dyeing was not compromised. This work pioneers the integration of iron and aluminum electrocoagulation in practical conditions, demonstrating enhanced contaminant removal efficiency, promoting water reuse in the textile industry, and enhancing environmental sustainability.