| 摘要 |
PROBLEM TO BE SOLVED: To provide a nitrogen oxide occlusion type exhaust gas pyrifying catalyst in which the occlusion function of nitrogen oxide is not lowered in the case sulfur oxide is contained in exhaust gas and superior heat resistance is provided and, therefore, the nitrogen oxide in the exhaust gas can be reduced and purified efficiently for a long period of time. SOLUTION: A nitrogen oxide occlusion type exhaust gas purifying catalyst is composed of (a) a composite oxide of barium and aluminum and (b) at least one element selected out of a group formed of Pt, Rh, Pd and Ir. In addition to the above components, at least one kind selected out of zirconium oxide and aluminum oxide, or gallium oxide can be contained as one catalyst component. |
