| 摘要 |
PROBLEM TO BE SOLVED: To provide an exhaust emission purifying catalyst capable of enhancing NOx purifying capacity in a lean atmosphere and sufficiently developing a function as a ternary catalyst and a use method capable of especially effectively developing the NOx purifying action thereof. SOLUTION: This exhaust emission purifying catalyst contains a powder (I) wherein palladium is supported on a porous material on which 1-7, 2-15 and 2-15 wt.% of Ce, La and Zr are supported in terms of oxide so as to be at least partially compounded and a composite oxide powder (II) represented by formula and, per 1 l of the catalyst, 100-300 g of the powder I and 40-100 g of the powder II are contained. Further, this catalyst is used in a lean burn engine car repeating air/fuel ratios of 10-15 or 10-14.8 and 15-50. |
