US4061713A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of exhaust gases
Assignee: Kali Chemie AG
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Filing: 1976-08-30
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Granted: 1977-12-06
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Expires: 1996-08-30
Abstract
Abstract Disclosed is a method of purifying exhaust gases from an internal combustion engine operated with a substantially stoichiometric fuel-to-air mixture, the gases having an L-value of from about 0.8 to 1.2, wherein the exhaust gases are brought into contact with a catalyst comprising molybdenum, rhodium and, optionally, platinum supported on a carrier.
Inventors
- 👤 Guenter Weidenbach
- 👤 Andre Lecloux
- 👤 Yves Gobillon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 18:29
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9445; B01D53/945; B01J; B01J23/00; B01J23/38; B01J23/54; B01J23/56; B01J23/64; B01J23/652; B01J23/6525; Y; Y02; Y02A; Y02A50/00; Y02A50/20; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
136 words
In a process for purifying exhaust gases from an internal combustion engine being operated with a substantially stoichiometric fuel-to-air mixture, said exhaust gases containing hydrocarbons (C n H 2n+2 ), carbon monoxide and nitric oxide and having an L-value of between about 0.8 and 1.2 where ##EQU5## and n is an integer, comprising the step of contacting said exhaust gases at an elevated temperature with a catalyst supported on a carrier which has been calcined at a temperature of at least about 800° C, whereby said hydrocarbons, carbon monoxide and nitric oxide are simultaneously removed from said exhaust gases, the improvement comprising said catalyst essentially consisting of said carrier having distributed thereon a mixture from about 0.01 to 0.1% by weight each of molybdenum and rhodium and from 0 to about 0.1% by weight of platinum.
Claim 2
Dependent Claim
136 words
In a process for purifying exhaust gases from an internal combustion engine being operated with a substantially stoichiometric fuel-to-air mixture, said exhaust gases containing hydrocarbons (C n H 2n+2 ), carbon monoxide and nitric oxide and having an L-value of between about 0.8 and 1.2 where ##EQU5## and n is an integer, comprising the step of contacting said exhaust gases at an elevated temperature with a catalyst supported on a carrier which has been calcined at a temperature of at least about 800° C, whereby said hydrocarbons, carbon monoxide and nitric oxide are simultaneously removed from said exhaust gases, the improvement comprising said catalyst essentially consisting of said carrier having distributed thereon a mixture from about 0.01 to 0.1% by weight each of molybdenum and rhodium and from 0 to about 0.1% by weight of platinum.
Claim 3
Dependent Claim
27 words
The process as defined by claim 1, wherein said molybdenum and rhodium are present in said catalyst in an atomic ratio of from about 1:1 to 4:1.
Claim 4
Dependent Claim
30 words
The process as defined by claim 1, wherein said catalyst contains from about 0.02 and 0.08% by weight of molybdenum and from about 0.02 to 0.04% by weight of rhodium.
Claim 5
Dependent Claim
13 words
The process as defined in claim 1, wherein said catalyst further comprises platinum.
Claim 6
Dependent Claim
20 words
The process as defined by claim 4, wherein said catalyst contains between about 0.01 and 0.1% by weight of platinum.
Claim 7
Dependent Claim
21 words
The process as defined by claim 3, wherein said catalyst further comprises from about 0.04 to 0.08% by weight of platinum.
Claim 8
Dependent Claim
13 words
The process as defined by claim 2, wherein said ratio is about 2:1.
Claim 9
Dependent Claim
23 words
The process as defined by claim 1, wherein the temperature of the exhaust gas is in the range of 300° to 1000° C.
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) | 1980-12-05 | 1981-06-06 | 1981-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-05 | 1985-06-06 | 1985-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-05 | 1989-06-06 | 1989-12-06 | $7700.00 | Window Closed / Lapsed |