Mutual effects of CO and benzene oxidation over Cu catalysts: The role of surface oxygen species and reaction pathways

CuMn, CuMnCe, and CuCe metal oxide catalysts were prepared and applied in oxidizing CO and benzene as representative volatile organic compounds (VOCs). Various characterization methods and in situ diffuse reflectance infrared Fourier transform spectra (DRIFTS) were used to explore mutual effects between CO and benzene oxidation and the role of reactive oxygen species. CuMn shows the highest activity in independent and simultaneous oxidation of CO and benzene due to its spinel Cu 1.5 Mn 1.5 O 4 structure, which gives abundant Cu + sites, acidic sites, O α , and O β . Cu + sites and O α benefit CO oxidation, while acidic sites, O α , and O β contribute to benzene oxidation, producing intermediates decomposable at low temperatures. Mechanism study reveals that benzene inhibits CO oxidation by competing for O α at low temperatures to retard carbonate intermediates formation. CO enhances benzene oxidation by promoting benzene preliminary oxidation and intermediates deep degradation. On CuMn, the formation and degradation of maleate and acetate are facilitated, while maleate and formate degradation are promoted on CuMnCe and CuCe, respectively.