| 摘要 |
<P>PROBLEM TO BE SOLVED: To restrain emission of HC and NOx in a low temperature period until a catalyst reaches the active temperature, without using an HC trap catalyst, in an exhaust emission control catalyst and an engine control device. <P>SOLUTION: This exhaust emission control catalyst has a carrier 11 forming a plurality of cell holes and a plurality of catalyst layers carried by these cell holes. The plurality of catalyst layers have an inner layer 12 composed of an auxiliary catalyst mainly composed of zeolite including a transition metal element for storing NOx in exhaust gas at the low temperature, and an outer layer 13 arranged adjacent to the surface side of the inner layer, including at least one component in alkaline metal and alkaline earth metal and composed of a main catalyst having the function of storing the NOx stored by the auxiliary catalyst, and is constituted so as to deliver the NOx to the main catalyst from the auxiliary catalyst when the main catalyst reaches the active temperature. <P>COPYRIGHT: (C)2010,JPO&INPIT |
