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In this paper, MCM-41 was synthesized by a soft template technique and MCM-41 supported CuO-CeO2 nano-sized catalysts with different Cu/Ce molar ratios were prepared by a deposition-precipitation method. N2 adsorption, HRTEM-EDS, H2-TPR, XPS characterization, as well as catalytic activity and durability tests for the catalytic combustion of chlorobenzene (CB) were conducted to explore the relationship between the structure and catalytic performance of the catalysts. It is revealed that CuCe(6:1)/MCM-41 has the highest activity and can completely catalyze the degradation of CB at 260 ℃. The reasons for the high activity of the catalysts are as follows:MCM-41, a type of mesoporous material which has large pore size and large specific surface area, is suitable as a catalyst carrier. The average diameter of nano-sized CuO and CeO2 particles is about 3-5 nm and adding CeO2 improves the dispersion of active component CuO, which are highly and evenly dispersed on the surface of MCM-41. Characterization results also explain why MCM-41 supported CuO-CeO2 with appropriate proportion can highly enhance the catalytic activity. The reason is that CeO2 acting as an oxygen-rich material can improve the mobility of oxygen species through continuous redox between Ce4+and Ce3+, and improve the catalytic performance of CuO for CB combustion. Besides, CuCe (6:1)/MCM-41 also displays good durability for CB combustion, both in the humid condition and in the presence of benzene, making it a promising catalytic material for the elimination of chlorinated VOCs.