Patent US4849398A successfully refreshed from Google Patents.
US4849398A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Catalyst for purifying exhaust gases
Assignee: Toyota Motor Corp
•
Filing: 1987-08-07
•
Granted: 1989-07-18
•
Expires: 2007-08-07
Abstract
Abstract A catalyst for purifying exhaust gases contains: a catalyst support, a perovskite double oxide comprising at least one alkaline earth metal oxide, lathanum oxide and cerium oxide, carried on the catalyst support, and noble metal catalyst components carried on the catalyst support. The catalyst for purifying exhaust gases according to the present invention offers an improved durability and purifying ratios for carbon monoxide CO, hydrocarbons HC and nitrogen oxides NOx.
Inventors
- 👤 Toshihiro Takada
- 👤 Shinichi Matsumoto
- 👤 Naoto Miyoshi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:43
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9445; B01D53/945; B01D71/00; B01D71/02; B01D71/024; B01D71/0271; B01J; B01J23/00; B01J23/38; B01J23/54; B01J23/56; B01J23/58; B01J23/63; B01J37/00; B01J37/02; B01J37/024; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12; Y10; Y10S; Y10S502/00; Y10S502/525
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
56 words
A catalyst for purifying exhaust gases containing: a catalyst support; a pervoskite double oxide consisting essentially of lanthanum oxide, cerium oxide and at least one alkaline earth metal oxide, said perovskite double oxide being carried on the surface of said catalyst support; and a noble metal catalyst component carried on the surface of said catalyst support.
Claim 2
Dependent Claim
56 words
A catalyst for purifying exhaust gases containing: a catalyst support; a pervoskite double oxide consisting essentially of lanthanum oxide, cerium oxide and at least one alkaline earth metal oxide, said perovskite double oxide being carried on the surface of said catalyst support; and a noble metal catalyst component carried on the surface of said catalyst support.
Claim 3
Dependent Claim
37 words
A catalyst for purifying exhaust gases according to claim 1, wherein an alumina layer is formed on the catalyst support, and perovskite double oxide and noble metal catalyst component are formed and disposed in said alumina layer.
Claim 4
Dependent Claim
21 words
A catalyst for purifying exhaust gases according to claim 1, wherein said alkaline earth metal is magnesium, calcium, strontium, or barium.
Claim 5
Dependent Claim
28 words
A catalyst for purifying exhaust gases according to claim 1, wherein said noble metal catalyst component comprises one or more of the elements platinum, palladium, iridium and rhodium.
Claim 6
Dependent Claim
19 words
A catalyst for purifying exhaust gases according to claim 1, wherein said alkaline earth metal oxide is barium oxide.
Claim 7
Dependent Claim
20 words
A catalyst for purifying exhaust gases according to claim 5, wherein said noble metal catalyst component is platinum and palladium.
Claim 8
Dependent Claim
37 words
A catalyst for purifying exhaust gases according to claim 1, wherein said perovskite double oxide has the chemical formula M.sub.1-x La.sub.x CeO.sub.3-δ, where M is an alkaline earth metal, (0<x<1), and δ is the oxygen deficiency amount.
Claim 9
Dependent Claim
31 words
A catalyst for purifying exhaust gases according to claim 1, wherein said perovskite double oxide has the chemical formula, Ba.sub.1-x La.sub.x CeO.sub.3-δ wherein 0<x<3/4 and δ0 is the oxygen deficiency amount.
Claim 10
Dependent Claim
30 words
A catalyst for purifying exhaust gases according to claim 2, wherein said perovskite double oxide is present in said alumina layer in an amount of 5 to 45% by weight.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-07-17 | 1993-01-16 | 1993-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-17 | 1997-01-16 | 1997-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-17 | 2001-01-16 | 2001-07-18 | $7700.00 | Window Closed / Lapsed |