Three-dimensionally ordered macro-porous CuO–CeO2 used for preferential oxidation of carbon monoxide in hydrogen-rich gases

Three-dimensionally ordered macro-porous (3DOM) CuO–CeO2 was prepared by using polystyrene (PS) colloidal crystal as the template, nitrate as the precursor and citric acid as the chelator. For CO preferential oxidation (PROX), at a higher space velocity of 160,000 mL gcat−1 h−1, complete CO conversion has been obtained between 150 °C and 175 °C. As the macro-pores of 3DOM are destroyed, complete CO conversion cannot be obtained even at a lower space velocity of 80,000 mL gcat−1 h−1, and likewise over particulate CuO–CeO2 catalysts. It is proposed that the ordered macro-pores in the 3DOM catalyst favor mass transfer, resulting in the excellent catalytic performance.