Design and Synthesis of Mn-Fe-Cu Multi-Metal Oxide Catalysts for Efficient Degradation of Organic Pollutants

Heterogeneous ozone-catalyzed oxidation technology is one of the effective ways of wastewater treatment, and the development of efficient ozone oxidation catalyst is the key to this process. Herein, this work proposes the design and synthesis of an efficient multi-metal composite oxide catalyst by metal salt precursor mixing-direct granulation. The successful loading of the main active metal components, such as Mn, Cu, Fe, etc. was clarified by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and other systematic characterizations, the specific surface area of the catalyst spheres produced by pelletizing could reach 231.699 m2/g, and the pore volume was 0.414 cm3/g. And after the optimization of the catalyst preparation conditions and oxidation process conditions, the removal rate of COD could reach more than 50% for the simulated wastewater, and the catalytic activity was basically kept stable in a long-cycle operation of 1000 h, which indicated that the prepared multi-metal composite oxide catalyst had good catalytic activity and stability. Finally, the EPR characterization clarified that the degradation of organic pollutants in the catalytic process was mainly dominated by the singlet oxygen and proposed a possible catalytic oxidation mechanism, which provided a reference for the synthesis of new high-efficiency ozone oxidation catalysts.