Oxidation catalyst for a diesel engine exhaust
AssigneeJohnson Matthey Japan Godo Kaisha
InventorTomoharu Hayama
Life of this patent
Estimating the term…
Abstract
An oxidation catalyst for treating an exhaust gas produced by a diesel engine comprises a catalytic region and a substrate, wherein the catalytic region comprises a catalytic material comprising: bismuth (Bi) or an oxide thereof; a Group 8 metal or an oxide thereof; a platinum group metal (PGM) selected from the group consisting of (i) platinum (Pt), (ii) palladium (Pd) and (iii) platinum (Pt) and palladium (Pd); and a support material, which comprises alumina, silica, a mixed oxide of alumina and a refractory oxide, a mixed oxide of silica and a refractory oxide, a composite oxide of alumina and a refractory oxide, a composite oxide of silica and a refractory oxide, alumina doped with a refractory oxide or silica doped with a refractory oxide.
Claims17
An oxidation catalyst for oxidizing carbon monoxide in an exhaust gas produced by a diesel engine, which oxidation catalyst comprising a catalytic region and a flow-through monolith substrate, wherein the catalytic region comprises a catalytic material consisting:
- bismuth (Bi) or an oxide thereof disposed or supported on a support material;
- a Group 8 metal, which is iron or an oxide thereof disposed or supported on the support material;
- a platinum group metal (PGM) selected from the group consisting of (i) platinum (Pt), and (ii) platinum (Pt) and palladium (Pd) having a ratio by weight of platinum to palladium of 15:1 to 1.5:1 when the platinum group metal (PGM) is platinum and palladium;
- wherein the support material comprises alumina doped with silica.
Dependencies are inferred from the claim text.