| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a noble metal-based catalyst high in performance and durability to be used for CO conversion reaction for decreasing the CO concentration in a reforming gas containing at least hydrogen gas, CO, and steam. <P>SOLUTION: The catalyst comprises a thermally treated cerium compound oxide defined by a formula (Ce)<SB>a</SB>(X)<SB>b</SB>(O)<SB>c</SB>(X denotes at least one element selected from among alkaline earth metals, La, Y, Mn, Fe and Sn; a and b independently denote the atomic ratio; a=10; 0.01≤b≤10; c denotes a number determined according to the oxidation degree of each constituent elements) and contains at least one noble metal component selected from among Pt, Pd, Rh, Ru and Ir. The components of the thermally treated cerium compound oxide catalyst show only the following diffraction peaks satisfying the following 2θ values of x-ray diffraction carried out Kα<SB>1</SB>radiation of Cu in a diffraction range of 20 to 50 degrees: 2θ<SB>1</SB>=28.7±0.4 degree, 2θ<SB>2</SB>=33.3±0.4 degree, and 2θ<SB>3</SB>=47.7±0.4 degree, showing the maximum peak intensity at 2θ<SB>1</SB>and having the peak intensity order as 2θ<SB>1</SB>>2θ<SB>3</SB>>2θ<SB>2</SB>. <P>COPYRIGHT: (C)2004,JPO |
