| 摘要 |
PROBLEM TO BE SOLVED: To clean exhaust gas whose ratio of HC/NOx is low under conditions including a low temperature below 150 deg.C. SOLUTION: This catalyst for cleaning an exhaust gas comprises a catalytic layer containing one or more components selected from a platinum(PD component, a palladium(Pd) component and a rhodium(Rh) component and one or more kinds components selected from an alkaline component, an alkaline earth component and a rare earth component as a first catalytic layer and a second catalytic layer containing βolite, formed on the first catalytic layer, and further, a third catalytic layer which is composed mainly of zeolite containing a copper(Cu) component and/or a cobalt(Co) component, formed on the second catalytic layer. In this case, the second catalytic layer structurally contains silica(SiO2 ). |
