Exhaust gas purifying catalyst and method for purifying exhaust gas
US6887443B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 10, 2002 |
| Grant date | May 3, 2005 |
| Priority date | — |
| Expiry date | Dec 10, 2022 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D2255/9022
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An exhaust gas purifying catalyst comprises a catalytic ingredient including rhodium, at least one of platinum and palladium, at least one of absorption materials for absorbing NOx, a porous carrier, and a monolithic support for supporting the catalytic ingredient. The exhaust gas purifying catalyst includes a plurality of catalytic layers containing at least a part of the catalytic ingredient, and rhodium is contained at least in an outermost layer of the catalytic layers. A rhodium amount in the catalytic ingredient is 0.5 g or more for each liter of the catalyst, and a rhodium amount contained in the outermost layer accounts for 80 wt % or more of a total rhodium amount. A weight of the catalytic layer at the outermost layer is 40 wt % or below of a total weight of the catalytic layers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.