Electro-oxidation: An Effective Alternative for the Degradation of Textile Dyes and Reduction of Toxicity in Industrial Effluents

Abstract

Purpose: This study aims to evaluate the efficiency of electro-oxidation as a treatment option for textile effluents containing industrial dyes, with the goal of minimizing their environmental impact.   Theoretical framework: The textile industry is known for its high water demand and generation of effluents containing dyes, posing an environmental challenge. Electro-oxidation is a promising technology for the degradation of pollutants that are difficult to mineralize.   Method: The treatment process and operational conditions were described, utilizing a Boron-Doped Diamond (BDD) electrode. Three ranges of electric current (6, 12, and 18 mA cm-2) were tested to degrade the Procion Yellow (PY) dye. The removal of the dye, energy consumption, reduction in Chemical Oxygen Demand (COD), Total Organic Carbon (TOC), and effluent toxicity were evaluated.   Results and conclusion: The treatment resulted in the removal of 91.4% of the dye, with an energy consumption of 88.4 kWh/m³ for a concentration of 150 mg/L of PY, following a first-order kinetics. Significant reductions in COD (74%) and TOC (85.2%) were observed. The effluent toxicity decreased at currents of 6 and 12 mA cm-2 but increased at 18 mA cm-2. Electro-oxidation proved to be a promising option for treating textile effluents containing industrial dyes.   Research implications: The results contribute to the advancement of science and socio-environmental management practices in the textile industry, providing a viable option for effluent treatment and reduction of environmental impact.   Originality/value: This study highlights the efficiency of electro-oxidation in the degradation of industrial dyes present in textile effluents, presenting relevant results on dye removal, energy consumption, COD and TOC reduction, as well as the evaluation of treated effluent toxicity.