Efficient fabrication of active CuO-CeO2/SBA-15 catalysts for preferential oxidation of CO by solid state impregnation

A facile solid state impregnation method was reported to prepare CuO-CeO2/SBA-15 catalysts for preferential oxidation of CO (CO-PROX). The catalysts were studied and compared with the counterpart from traditional wet impregnation. All catalysts together with a bulk CuO-CeO2 were characterized by XRD, N-2 sorption, TEM, XPS, FT-IR of CO adsorption and H-2-TPR. Results showed that: (1) both copper and ceria were well dispersed on SBA-15, and by adoption of a supported CuO-CeO2 configuration, the CO-PROX activities were greatly enhanced, which could be attributed to the distinct reduction of ceria size; (2) the optimum copper loading was 5 wt%, and obvious decrease of CO2 selectivity was observed at higher loading; (3) in comparison with wet impregnation, the solid state impregnation displayed advantages of increased interfacial CuO-CeO2 entities and enhanced interaction between CuO and CeO2, which increased the active site and upgraded the CO-PROX activity resultantly. As well, the reason accounting for the different properties was tentatively discussed. On the basis of the preliminary results, it is supposed the solid state impregnation will find unique application in fabrication of multi-component heterogeneous catalysts. (C) 2013 Elsevier B.V. All rights reserved.