Biochar-supported copper/manganese oxide composite (CuOx-MnOy@BC) as a useful Fenton-like catalyst was synthesized and characterized. The nanocatalyst was applied to eliminate metronidazole (MNZ) from an aqueous wastewater. 99.7% of MNZ and 55.2% of the total organic carbon (TOC) removal were achieved at 20 mM of H2O2, 0.75 mg/L of CuOx-MnOy@BC, and 20 mg/L of MNZ under neutral pH, and the catalyst remained active under a wide range of pH. Free radicals quenching studies verified the dominant role of hydroxyl radicals produced through activation of H2O2 with the synergistic effect of Cu2+, Mn2+, persistent free radicals, and visible light. The reusability of catalyst was confirmed through five repeated uses.
