Comparative Study of Fenton and Photo-Fenton Processes for the Treatment of Distillery Wastewater: Pollutant Removal Efficiency and Kinetic Analysis

This study investigates the optimization of key parameters (Fe²⁺ dosage, H₂O₂ concentration and pH) in the Fenton and photo-Fenton processes for the treatment of distillery wastewater (DWW). The effects of these parameters on COD removal efficiency were evaluated and the results demonstrated that Fe²⁺ dosage, H₂O₂ concentration and pH significantly influence the treatment efficiency. The highest COD removal efficiency in the Fenton process was achieved at Fe²⁺ 1.25 g L⁻¹, H₂O₂ 1110 mg L⁻¹ and pH 3, while the photo-Fenton process showed enhanced efficiency, particularly at lower pH values and with UV light exposure, which accelerated the reaction kinetics. Kinetic modeling revealed that the Fenton process followed pseudo-first-order kinetics, while the photo-Fenton process adhered to second-order kinetics, with UV light playing a crucial role in improving the reaction rate. ANOVA analysis confirmed that all three parameters were statistically significant, with pH being the most influential factor. The study highlights that both Fenton and photo-Fenton processes are effective for treating DWW, with the photo-Fenton process demonstrating superior performance due to the catalytic effect of UV light. These findings offer valuable insights into optimizing these processes for industrial-scale wastewater treatment, with potential for cost-effective and sustainable applications in distillery and similar industries. Future research could explore hybrid oxidation technologies and alternative UV sources to further improve process efficiency and sustainability.