| 摘要 |
PROBLEM TO BE SOLVED: To obtain an NOx occluding agent which has excellent occluding performance for NOx contained in an automobile exhaust gas, or the like. SOLUTION: The NOx occluding agent contains (A) a composite oxide of zirconium and a metal other than zirconium selected from the groups consisting of alkali metals, alkaline-earth metals and rare earth metals, and (B) at least one metallic compound selected from the groups consisting of zirconium oxide, the oxide of metals other than zirconium, and the carbonates of metals other than zirconium. |
