Preferential oxidation of CO in excess H2 over CeO2/CuO catalyst: Effect of calcination temperature

Different from the classical configuration CuO/CeO₂ catalyst, the inverse configuration CeO₂/CuO catalyst (atomic ratio of Ce/Cu = 10/100) was prepared by impregnation method. Five calcination temperatures were selected to investigate the interaction between CeO₂ and CuO support. It is found that as calcination temperature increased from 500 to 900°C, sintering of CeO₂ particles on the support occurred together with the diffusion of a portion of Ce⁴⁺ ions into CuO crystals, forming solid solution. Formation of interface complex Ce-O-Cu was suggested by TPR measurements. The catalyst calcined at 700°C gives the highest activity for preferential oxidation of CO in excess H₂ stream.