Heterogeneous Fenton-like reactions with a novel hybrid Cu-Mn-O catalyst for the degradation of benzophenone-3 in aqueous media

This study focuses on the heterogeneous Fenton-like reaction performed over a novel hybrid Cu-Mn-O catalyst for the degradation of a model compound benzophenone-3 (BP-3) in aqueous media. The hybrid Cu-Mn-O catalysts with different Cu/Mn molar ratios were synthesized using co-precipitation and hydrothermal methods, and their composition and morphology were characterized using XRD and SEM analyses. Key parameters including the Cu/Mn ratio in the synthesis, pH and titration of H2O2 were shown to significantly influence the degradation of BP-3. A hybrid catalyst with a chemical composition of Cu1.4Mn1.6O4, Mn3O4, and Mn2O3 exhibiting a morphology of nanofibers and nanoparticles demonstrated the highest catalytic activity in the degradation of BP-3. After 240 min of degradation, 81.5% of BP-3 was removed, which could be mostly related to the presence of hydroxyl radicals (˙OH). Unlike the conventional Fenton reaction that performs well under highly acidic conditions, BP-3 can be degraded in a wider pH range (2.6-7.1) in the Fenton-like reaction presented herein. Considering the mild conditions used for this Fenton-like system, this novel hybrid catalyst remains promising for wastewater treatment.