NOx PURIFYING CATALYST

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 a ² zeolite containing iron element and a cerium oxide material and a second catalyst layer containing a noble metal, a cerium oxide material and a heat-resistant inorganic oxide. 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.