US3914376A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Layered rhodium and nickel catalyst for NO{HD x {b reduction
Assignee: Monsanto Co
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Filing: 1973-02-08
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Granted: 1975-10-21
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Expires: 1993-02-08
Abstract
Abstract The invention concerns a catalyst in which a nickel component is deposited on an inert support, followed by an alumina coating and a rhodium component. The catalyst is particularly useful for removing nitrogen oxides from automotive exhaust.
Inventors
- 👤 George E Barker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:25
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9404; B01D53/9409; B01D53/9413; B01J; B01J23/00; B01J23/70; B01J23/89; B01J23/892; B01J37/00; B01J37/02; B01J37/024; B01J37/0244; B01D2251/00; B01D2251/10; B01D2251/102; B01D2255/00; B01D2255/10; B01D2255/102; B01D2255/1025; B01D2255/20; B01D2255/207; B01D2255/20753; B01D2255/209; B01D2255/2092
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
47 words
THE PROCESS OF TREATING EXHAUST OF COMBINATION ENGINES TO REMOVE NITROGEN OXIDES THEREFROM WHICH COMPRISES CONTACTING SUCH EXHAUST AT ELEVATED TEMPERATURE UNDER REDUCING CONDITIONS WITH A CATALYST COMPRISING NICKEL FIXED ON AN INERT SUPPORT AND HAVING ALUMINA DEPOSITED OVER THE NICKEL AND RHODIUM DISPERSED UPON THE ALUMINA.
Claim 2
Dependent Claim
47 words
THE PROCESS OF TREATING EXHAUST OF COMBINATION ENGINES TO REMOVE NITROGEN OXIDES THEREFROM WHICH COMPRISES CONTACTING SUCH EXHAUST AT ELEVATED TEMPERATURE UNDER REDUCING CONDITIONS WITH A CATALYST COMPRISING NICKEL FIXED ON AN INERT SUPPORT AND HAVING ALUMINA DEPOSITED OVER THE NICKEL AND RHODIUM DISPERSED UPON THE ALUMINA.
Claim 3
Dependent Claim
45 words
The process of claim 1 in which the amount of nickel is in the range of 5 to 20 weight parts, the amount of alumina 2 to 6 weight parts, and rhodium up to 0.005 weight parts, per 100 weight parts of inert support material.
Claim 4
Dependent Claim
14 words
The process of claim 1 in which the support is a monolithic ceramic structure.
Claim 5
Dependent Claim
38 words
The process of claim 1 in which the engine is operated with a rich air-to-fuel ratio and supplemental air is added to the exhaust prior to contacting the catalyst in an amount which does not make conditions oxidizing.
Claim 6
Dependent Claim
21 words
The process of claim 4 in which the amount of added air is at least 3% by volume of the exhaust.
Claim 7
Dependent Claim
25 words
The process of claim 4 in which the amount of added air is in the range of 3 to 6% by volume of the exhaust.
Claim 8
Dependent Claim
50 words
The process of claim 4 in which the air-to-fuel range of the engine and the amount of supplemental air are in relationship such that the CO/O2 ratio in the exhaust after addition of the air is in the range of 1.5 to 5 substantially throughout the said air-to-fuel ratio range.
Claim 9
Dependent Claim
54 words
The process of claim 4 in which the air-to-fuel ratio range of the engine and the amount of added air are in combination such that the amount of added air approaches the maximum which can be added without preventing substantially complete reduction of the nitrogen oxides at the lean edge of the operating range.
Claim 10
Dependent Claim
15 words
The process of claim 4 in which the inert support is a monolithic ceramic structure.
Claim 11
Dependent Claim
24 words
The process of claim 4 in which temperatures at the inlet to a converter containing the catalyst are at times in excess of 700*C.
Claim 12
Dependent Claim
23 words
The process of claim 4 in which the amount of rhodium is no more than 0.02 part by weight of the inert support.
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) | 1978-10-20 | 1979-04-21 | 1979-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-20 | 1983-04-21 | 1983-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-20 | 1987-04-21 | 1987-10-21 | $7700.00 | Window Closed / Lapsed |