Catalyst for purifing exhaust gases
US4921829A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 1988 |
| Grant date | May 1, 1990 |
| Priority date | — |
| Expiry date | Dec 21, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S502/525
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A catalyst for purifying exhaust gases comprises: a perovskite-type complex oxide represented by the general formula Ln.sub.1-x A.sub.x MO.sub.3, wherein Ln represents at least one rare earth metal, A presents at least one alkaline earth metal and M represents at least one transition metal, and 0<x<1; at least one heat resistant complex oxide; and at least one precious metal. The heat resistant complex oxide is one of ABO.sub.3, LnAlO.sub.3 or Ln.sub.2 B.sub.2 O.sub.7, wherein A represents at least one alkaline earth metal, B represents at least one of Ti, Zr and Hf, and Ln represents at least one rare earth metal, and the precious metal is at least one of Pt, Pd, Rh, Ir, Ru and Os. The catalyst is usable as a temperature of 900.degree. C. or above without sintering or reduction of a catalytic activity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.