Independent Acidic pH Reactivity of Non-Iron-Fenton Reaction Catalyzed by Copper-Based Nanoparticles for Fluorescent Dye Oxidation

The process of hydrogen peroxide decomposition, facilitated by copper oxide nanoparticles, produces reactive oxidants that possess the ability to oxidize multiple pollutants. CuO/Cu₂O hybrid nanoparticles were successfully synthesized through a thermal decomposition route and applied as a heterogeneous catalytic oxidant for a fluorescent dye, namely Basic Violet 10 (BV10) dye. The microstructure and morphology of the prepared catalyst were evaluated via X-ray diffraction (XRD) and a field-emission scanning electron microscope (FE-SEM), respectively. The produced nanoparticles (NPs) were induced through ultraviolet light as a green photodecomposition technology. The system parameters were investigated, and the optimal initial NP concentration, H₂O₂ concentration, and pH were assessed. The highest removal rate corresponding to 82% was achieved when 40 and 400 mg/L of NPs and H₂O₂ were introduced, respectively. The system could operate at various pH values, and the alkaline pH (8.0) was efficient in proceeding with the oxidation system that overcomes the limitation of the homogeneous acidic Fenton catalyst. The introduced catalyst demonstrated consistent sustainability, achieving a notable removal rate of 68% even after six consecutive cycles of use. This innovative technique’s accomplishment examines the feasibility of utilizing copper as a replacement for iron in the Fenton reaction, demonstrating efficacy over an extended pH range. Finally, the temperature effectiveness of the reaction showed that the reaction is exothermic in nature, working at a low energy barrier (20.4 kJ/mol) and following the pseudo-second-order kinetic model.