US4497783A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Exhaust emission catalyst
Assignee: Wyeth Holdings LLC
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Filing: 1982-08-05
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Granted: 1985-02-05
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Expires: 2002-08-05
Abstract
Abstract An improved catalyst for the conversion of exhaust emissions from internal combustion engines comprises platinum on a refractory support and sodium or potassium or a combination of sodium and potassium in an amount sufficient to significantly broaden the A/F window for said catalyst. In place of sodium or potassium, barium may be used, although it is less effective than sodium or potassium. A preferred catalyst composition comprises platinum, palladium and rhodium on a refractory support and sodium or potassium in an amount sufficient to significantly broaden the A/F window of said catalyst.
Inventors
- 👤 William A. Barber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:30
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/38; B01J23/54; B01J23/56; B01J23/63; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9445; B01D53/945; B01J23/58; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
92 words
In a process of catalytic conversion of internal combustion engine exhaust, including catalytic oxidation of CO and hydrocarbon components and catalytic reduction of NO x components in said emissions, wherein the catalyst comprises platinum with or without palladium and with or without rhodium on a refractory support in amounts effective for the defined oxidation and reduction, the improvement wherein the AF window for said catalyst is broadened by at least 0.25 AF unit by presence in said catalyst of at least one member selected from the group consisting of sodium and potassium.
Claim 2
Dependent Claim
92 words
In a process of catalytic conversion of internal combustion engine exhaust, including catalytic oxidation of CO and hydrocarbon components and catalytic reduction of NO x components in said emissions, wherein the catalyst comprises platinum with or without palladium and with or without rhodium on a refractory support in amounts effective for the defined oxidation and reduction, the improvement wherein the AF window for said catalyst is broadened by at least 0.25 AF unit by presence in said catalyst of at least one member selected from the group consisting of sodium and potassium.
Claim 3
Dependent Claim
15 words
A process defined by claim 1, wherein the platinum is present in combination with sodium.
Claim 4
Dependent Claim
15 words
A process defined in claim 1, wherein the platinum is present in combination with potassium.
Claim 5
Dependent Claim
17 words
A process defined by claim 1, wherein the platinum is present in combination with palladium and sodium.
Claim 6
Dependent Claim
17 words
A process defined by claim 1, wherein the platinum is present in combination with palladium and potassium.
Claim 7
Dependent Claim
17 words
A process defined by claim 1, wherein the platinum is present in combination with rhodium and sodium.
Claim 8
Dependent Claim
17 words
A process defined by claim 1, wherein the platinum is present in combination with rhodium and potassium.
Claim 9
Dependent Claim
18 words
A process defined by claim 1, wherein the platinum is present in combination with palladium, rhodium and sodium.
Claim 10
Dependent Claim
18 words
A process defined by claim 1, wherein the platinum is present in combination with palladium, rhodium and potassium.
References Cited (Backward Citations)
US3388077A
Cited
US4369132A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-05 | 1988-08-06 | 1989-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-05 | 1992-08-06 | 1993-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-05 | 1996-08-06 | 1997-02-05 | $7700.00 | Window Closed / Lapsed |