EXHAUST GAS-PURIFYING CATALYST

摘要

An exhaust gas-purifying catalyst is disclosed. The catalyst includes a filter substrate having a wall flow structure and a catalyst bed formed on cell partition walls of the filter substrate. The catalyst bed contain a porous oxide, a noble metal supported on the porous oxide, and an alkali metal supported on the porous oxide in an amount of 0.6 mole or more per 1L of the filter substrate. Since a large amount of alkali metal is supported, the alkali metal is likely to contact particulate material(PM) mainly containing carbon. Accordingly, the oxidation temperature of the PM can be lowered. Thus, it is possible to oxidize PM even at a low temperature of 300 °C or below.