Advances in dye degradation in industrial textile effluent: Unveiling the potential of Fenton, photo-Fenton, and helio-photo-Fenton processes for environmental conservation

The contamination of soil and water by coloring effluents is a significant environmental concern, prompting the adoption of advanced oxidation processes (AOPs). Fenton oxidation, a commonly used method for treating industrial effluents, generates hydroxyl radicals •OH) that oxidize pollutants, leading to their mineralization. The combination of UV radiation with Fenton’s reagent, particularly for landfill leachates, enhances this process by generating additional hydroxyl radicals through photolysis. This study applied UV light in conjunction with a conventional Fenton process under optimized conditions: pH 3, iron(II) sulfate concentration of 3.29×10-4 mol/L, hydrogen peroxide concentration of 0.7×10-3 mol/L, and a temperature of 25°C. The degradation of textile dyes (FBB Bezathren Red, FFB Bezathren Green, RS Bezathren Blue) and their mixtures, as well as real liquid waste from the textile industry, was investigated. The Helio photo-Fenton process demonstrated exceptional efficiency, achieving mineralization rates of 90% for synthetic mixtures, 96% for textile effluent, and 81.92%, 81.20%, and 96.77% for FBB Bezathren Red, FFB Bezathren Green, and RS Bezathren Blue, respectively. The process efficacies for removing chemical oxygen demand (COD) and turbidity reached 80% and 90%, respectively. In summary, the Helio photo-Fenton process, which utilizes renewable energy, demonstrated higher degradation efficiency compared to artificial light, highlighting its potential for sustainable development.