Exhaust gas-purifying catalyst
AssigneeCataler Corporation
InventorsYoshinori Yamashita, Shohei Tomita, Daisuke Ochiai, Masatoshi Ikebe
Life of this patent
Estimating the term…
Abstract
An exhaust gas-purifying catalyst of the present invention comprising a substrate, a first catalyst layer comprising a first supported catalyst, a second supported catalyst, palladium, and a first nitrogen oxide storage material, and a second catalyst layer comprising a third supported catalyst having an alloying rate of platinum and palladium of 40% or more and a second nitrogen oxide storage material, wherein a mass of the second supported catalyst is greater than a mass of the first supported catalyst and greater than a mass of the third supported catalyst.
Claims9
An exhaust gas-purifying catalyst comprising a substrate and a catalyst layer supported on the substrate, wherein the catalyst layer contains:
- a first supported catalyst containing a first heat resistant carrier and rhodium supported on the first heat resistant carrier;
- a second supported catalyst containing a second heat resistant carrier and platinum supported on the second heat resistant carrier, the second heat resistant carrier containing an inorganic oxide which has a spinel structure and contains alumina and magnesia;
- a third supported catalyst containing a third heat resistant carrier and platinum and a noble metal other than platinum which are supported on the third heat resistant carrier;
- and
- a nitrogen oxide storage material,
- wherein a proportion of a mass of platinum contained in the second supported catalyst in an entire mass of platinum contained in the catalyst layer is in a range of 15% by mass to 35% by mass.
Dependencies are inferred from the claim text.