초록

An exhaust gas emission control catalyst includes an under catalyst layer containing at least one of barium and lanthanum and an over catalyst layer containing an agent for absorbing water in a gas, at least one of the under catalyst layer and over catalyst layer containing catalytic metal.

대표청구항 ▼

[ What is claimed is:] [1.] A catalyst construction for purifying a gas comprising:a catalyst carrier;an under catalyst layer coated on said catalyst carrier for absorbing oxides of nitrogen (NOx) in a gas, said under catalyst layer containing platinum and at least one of barium and lanthanum; andan

[ What is claimed is:] [1.] A catalyst construction for purifying a gas comprising:a catalyst carrier;an under catalyst layer coated on said catalyst carrier for absorbing oxides of nitrogen (NOx) in a gas, said under catalyst layer containing platinum and at least one of barium and lanthanum; andan over catalyst layer coated on said under catalyst layer for lowering emission level of oxides of nitrogen (NOx) and hydrocarbons (HC), said over catalyst layer containing crystalline metal silicate carrying at least one of barium and rhodium.