Catalyst for purifying automotive exhaust gases
US3972837A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 1974 |
| Grant date | Aug 3, 1976 |
| Priority date | — |
| Expiry date | Jun 28, 1994 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S502/525
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
This invention relates to catalyst for use in the control of atmospheric pollution and, in particular, to the purification of exhaust gases from internal combustion engines. Specific catalysts of the present invention comprise: A. ruthenium or an alloy thereof and a metal oxide capable of forming a stable mixed oxide (or "ruthenite") with ruthenium dioxide; B. a compound formed by ruthenium dioxide and a metal oxide capable of forming a stable mixed oxide (or ruthenite) with ruthenium dioxide; and C. a mixed oxide containing ruthenium, the oxide being selected from the group consisting of oxides of the pyrochlore type A.sub.2 B.sub.2 O.sub.7, the perovskite type ABO.sub.3, the ilmenite type B.sub.2 O.sub.3 and the spinel type AB.sub.2 O.sub.4. Particularly good results have been obtained where the platinum/ruthenium ratio is within the range 25- 95 wt.% platinum and 5 - 75 wt.% ruthenium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.