Selective oxidation of CO in excess hydrogen over catalysts

Ce x Zr 1 - x O 2 ( x = 0.1 –0.5) mixed oxides were prepared as supports of CuO / Ce x Zr 1 - x O 2 catalysts. They were characterized and used in the selective oxidation of carbon monoxide (CO) in excess hydrogen. An appropriate amount of zirconium incorporated into CeO 2 not only increased the mobility of lattice oxygen but also promoted the activity of the selective CO oxidation. The promotion of CO oxidation was weakened as the amount of Zr 4 + increased above 10% ( 1 - x > 0.1 ) . The temperature ( T 100 ) of 7 % CuO / Ce 0.9 Zr 0.1 O 2 for complete conversion was about 10 degrees lower than that of 7 % CuO / CeO 2 (378 K), and the selectivity achieved was nearly 100%. The activity of the 7 % CuO / Ce 0.9 Zr 0.1 O 2 catalyst was weakened in the feed in the presence of CO 2 and H 2 O , but the selectivity and stability of the catalyst were maintained. The 7 % CuO / Ce 0.9 Zr 0.1 O 2 catalyst exhibited not only good activity that was comparable with that of the noble metal catalyst of 5 % Pt / Al 2 O 3 but also good selectivity of much greater than 5 % Pt / Al 2 O 3 .