Lanthanum containing catalyst for treating automotive exhaust
US4923842A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 11, 1988 |
| Grant date | May 8, 1990 |
| Priority date | — |
| Expiry date | Oct 11, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
This invention relates to an improved catalytic composite for treating an exhaust gas comprising a first support which is a refractory inorganic oxide, having dispersed thereon at least one oxygen storage component and at least one noble metal component and having dispersed immediately thereon an overlayer comprising lanthanum oxide and optionally a second support which is a refractory inorganic oxide. The first and second support may be selected from the group consisting of alumina, silica, titania, zirconia and aluminosilicates with alumina being preferred. Additionally, the noble metal component may be selected from the group consisting of platinum, palladium, rhodium, ruthenium and iridium. The oxygen storage component is an oxide of a metal which includes cerium, iron, nickel, cobalt lanthanum, neodymium, praesodymium, etc. and mixtures thereof. This invention also relates to a process for treating automotive exhaust comprising contacting the exhaust with the catalytic composite described above. The catalytic composite shows improved activity, especially for eliminating NO.sub.x, after extensive durability testing and also minimizes the formation of H.sub.2 S.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.