US4702897A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lead-tolerant catalyst system and method for treating exhaust gas containing lead compounds
Assignee: Signal Applied Technologies Inc
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Filing: 1985-09-30
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Granted: 1987-10-27
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Expires: 2005-09-30
Abstract
Abstract A lead-resistant exhaust gas oxidation catalytic composite is disclosed. The composite comprises a support material comprising a refractory inorganic oxide having deposited thereon a catalytic component selected from the Group consisting of platinum, palladium, iridium, rhodium and mixtures thereof and having dispersed thereover a protective coating of zirconia. Also disclosed is a method for effecting oxidation of noxious exhaust gases comprising hydrocarbons, carbon monoxide and lead compounds. Additionally, a method for oxidizing an exhaust gas from an internal combustion engine operating upon leaded fuel is also disclosed.
Inventors
- 👤 Isik Onal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:57
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9445; B01D53/945; B01J; B01J23/00; B01J23/38; B01J23/40; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
65 words
A method for effecting oxidation of noxious exhaust gases comprising hydrocarbons, carbon monoxide and lead compounds, said method comprising contacting said gases at oxidation conditions with a catalytic composite consisting essentially of a honeycomb ceramic or metallic carrier having deposited thereon an alumina support layer, said alumina layer having deposited thereon a platinum catalytic component and having dispersed immediately thereover a protective layer of zirconia.
Claim 2
Independent Claim
65 words
A method for effecting oxidation of noxious exhaust gases comprising hydrocarbons, carbon monoxide and lead compounds, said method comprising contacting said gases at oxidation conditions with a catalytic composite consisting essentially of a honeycomb ceramic or metallic carrier having deposited thereon an alumina support layer, said alumina layer having deposited thereon a platinum catalytic component and having dispersed immediately thereover a protective layer of zirconia.
Claim 3
Dependent Claim
31 words
The method of claim 1 further characterized in that the weight ratio of zirconia to refractory oxide is less than about 1:1 based on the weight of zirconia and refractory oxide.
Claim 4
Independent Claim
80 words
A method for oxidizing carbon monoxide, and hydrocarbons contained in an exhaust gas from an internal combustion engine operating upon fuel containing at leas 0.01 g per liter of lead which method comprises contacting the exhaust gas at oxidation conditions with a catalytic composite consisting essentially of a honeycomb ceramic or metallic carrier having deposited thereon an alumina support layer, said alumina layer having deposited thereon a platinum catalytic component and having dispersed immediately thereover a protective layer of zirconia.
Claim 5
Independent Claim
80 words
A method for oxidizing carbon monoxide, and hydrocarbons contained in an exhaust gas from an internal combustion engine operating upon fuel containing at leas 0.01 g per liter of lead which method comprises contacting the exhaust gas at oxidation conditions with a catalytic composite consisting essentially of a honeycomb ceramic or metallic carrier having deposited thereon an alumina support layer, said alumina layer having deposited thereon a platinum catalytic component and having dispersed immediately thereover a protective layer of zirconia.
Claim 6
Dependent Claim
31 words
The method of claim 3 further characterized in that the weight ratio of zirconia to refractory oxide is less than about 1:1 based on the weight of zirconia and refractory oxide.
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) | 1990-10-26 | 1991-04-27 | 1991-10-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-10-26 | 1995-04-27 | 1995-10-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-10-26 | 1999-04-27 | 1999-10-27 | $7700.00 | Window Closed / Lapsed |