| 摘要 |
PROBLEM TO BE SOLVED: To effectively reduce a carbon monoxide concn. in a hydrogen-rich gas over a wide temp. range. SOLUTION: A CO selectively oxidizing part 34 is provided in a fuel cell system 10, and the carbon monoxide concn. in a reformed gas formed at a reforming part 32 is reduced to a very low level at this CO selectively oxidizing part 34. A CO selectively oxidizing catalyst carrying ruthenium on a carrier consisting of zirconia is packed at the CO selectively oxidizing part 34. In the ruthenium catalyst deposited on the zirconia carrier, a strict temp. control is not required at the CO selectively oxidizing part 34 since a temp. range capable of sufficiently reducing the carbon monoxide concn. is very wide as 80-200 deg.C. The carbon monoxide concn. is stably reduced even in the case when a loading at the CO selectively oxidizing part 34 is increased and decreased by fluctuating a loading and an inside temp. of the CO selectively oxidizing part 34 is changed. |
