| 摘要 |
Disclosed is a NOx purifying catalyst which is capable of removing NOx sufficiently efficiently even during operations at low temperatures such as operations in diesel cars. Specifically disclosed is a NOx purifying catalyst for processing NOx in an exhaust gas by performing lean/rich control of air-fuel ratio of the exhaust gas. This NOx purifying catalyst comprises at least a first catalyst layer containing aβzeolite containing iron element and a second catalyst layer containing a noble metal, a cerium oxide material and a specific zirconium oxide material. The second catalyst layer and the first catalyst layer are sequentially arranged on a carrier in such a manner that the first catalyst layer forms the uppermost layer.
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