US4863893A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low temperature light off ammonia oxidation
Assignee: BASF Catalysts LLC
•
Filing: 1986-08-06
•
Granted: 1989-09-05
•
Expires: 2006-08-06
Abstract
Abstract Platinum-rhodium and platinum-palladium-rhodium gauzes bearing a high surface area coating (in excess of 50 cm 2 /g) of platinum ease initiation of ammonia oxidation.
Inventors
- 👤 Robert J. Farrauto
- 👤 Hyo C. Lee
- 👤 W. Robert Hatfield
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:02
CPC Classifications
C; C01; C01B; C01B21/00; C01B21/20; C01B21/24; C01B21/26; C01B21/265; B; B01; B01J; B01J23/00; B01J23/38; B01J23/40; B01J23/46; B01J23/464; B01J35/00; B01J35/50; B01J35/58; C01B21/267
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
85 words
A method of forming a catalytic gauze element comprising forming a woven mesh consisting essentially of platinum, rhodium and optionally palladium, grounding said mesh electrically, and spraying electrically charged droplets comprising a thermally decomposable platinum compound dispersed in a volatile liquid onto said mesh and thereafter evaporating said volatile liquid and decomposing said thermally decomposable platinum compound to form a high surface area coating of platinum upon said mesh, the surface area of the resulting coated mesh being at least about 50 cm 2 /g.
Claim 2
Independent Claim
85 words
A method of forming a catalytic gauze element comprising forming a woven mesh consisting essentially of platinum, rhodium and optionally palladium, grounding said mesh electrically, and spraying electrically charged droplets comprising a thermally decomposable platinum compound dispersed in a volatile liquid onto said mesh and thereafter evaporating said volatile liquid and decomposing said thermally decomposable platinum compound to form a high surface area coating of platinum upon said mesh, the surface area of the resulting coated mesh being at least about 50 cm 2 /g.
Claim 3
Dependent Claim
30 words
The method of claim 1 wherein said volatile liquid is an aqueous liquid and the surface area of the resulting coated mesh is at least about 250 cm 2 /g.
Claim 4
Dependent Claim
22 words
The method of claim 2 wherein the surface area of the resulting coated mesh is at least about 350 cm 2 /g.
Claim 5
Dependent Claim
22 words
The method of claim 2 wherein the surface area of the resulting coated mesh is at least about 500 cm 2 /g.
Claim 6
Dependent Claim
39 words
A catalytic element comprising filaments consisting essentially of platinum, rhodium and optionally palladium, said filaments having a high surface area coating consisting essentially of platinum formed thereon, the surface area of said catalytic element exceeding 50 cm 2 /g.
Claim 7
Dependent Claim
39 words
A catalytic element comprising filaments consisting essentially of platinum, rhodium and optionally palladium, said filaments having a high surface area coating consisting essentially of platinum formed thereon, the surface area of said catalytic element exceeding 50 cm 2 /g.
Claim 8
Dependent Claim
19 words
The catalytic element of claim 2 wherein the surface area of said catalytic element exceeds 250 cm 2 /g.
Claim 9
Dependent Claim
19 words
The catalytic element of claim 2 wherein the surface area of said catalytic element exceeds 350 cm 2 /g.
Claim 10
Dependent Claim
19 words
The catalytic element of claim 2 wherein the surface area of said catalytic element exceeds 500 cm 2 /g.
Claim 11
Dependent Claim
31 words
The catalyst of one of claims 5, 6, 7, or 8 wherein the weight of said platinum coating is at least about 0.5 grams per square meter of bulk gauze area.
Claim 12
Dependent Claim
31 words
The catalyst of one of claims 5, 6, 7 or 8 wherein the weight of said platinum coating is at least about 3.0 grams per square meter of bulk gauze area.
Claim 13
Dependent Claim
31 words
The catalyst of one of claims 5, 6, 7 or 8 wherein the weight of said platinum coating is at least about 4.0 grams per square meter of bulk gauze area.
Claim 14
Independent Claim
79 words
A method of forming a catalytic gauze element comprising forming a woven mesh consisting essentially of platinum, rhodium and optionally palladium, and spraying droplets comprising a thermally decomposable platinum compound dispersed in a volatile liquid onto said mesh and thereafter evaporating said volatile liquid and decomposing said thermally decomposable platinum compound to form a high surface area coating of platinum upon said mesh, the surface area of the resulting coated mesh being at least about 50 cm 2 /g.
Claim 15
Independent Claim
79 words
A method of forming a catalytic gauze element comprising forming a woven mesh consisting essentially of platinum, rhodium and optionally palladium, and spraying droplets comprising a thermally decomposable platinum compound dispersed in a volatile liquid onto said mesh and thereafter evaporating said volatile liquid and decomposing said thermally decomposable platinum compound to form a high surface area coating of platinum upon said mesh, the surface area of the resulting coated mesh being at least about 50 cm 2 /g.
Claim 16
Dependent Claim
30 words
The method of claim 6 wherein said volatile liquid is an aqueous liquid and the surface area of the resulting coated mesh is at least about 250 cm 2 /g.
Claim 17
Dependent Claim
22 words
The method of claim 7 wherein the surface area of the resulting coated mesh is at least about 350 cm 2 /g.
Claim 18
Dependent Claim
22 words
The method of claim 7 wherein the surface area of the resulting coated mesh is at least about 500 cm 2 /g.
Claim 19
Independent Claim
77 words
A method of forming a catalytic gauze element comprising forming a woven mesh consisting essentially of platinum, rhodium and optionally palladium, and depositing a thermally decomposable platinum compound dispersed in a volatile liquid onto said mesh and thereafter evaporating said volatile liquid and decomposing said thermally decomposable platinum compound to form a high surface area coating of platinum upon said mesh, the surface area of the resulting coated mesh being at least about 50 cm 2 /g.
Claim 20
Independent Claim
77 words
A method of forming a catalytic gauze element comprising forming a woven mesh consisting essentially of platinum, rhodium and optionally palladium, and depositing a thermally decomposable platinum compound dispersed in a volatile liquid onto said mesh and thereafter evaporating said volatile liquid and decomposing said thermally decomposable platinum compound to form a high surface area coating of platinum upon said mesh, the surface area of the resulting coated mesh being at least about 50 cm 2 /g.
Claim 21
Dependent Claim
30 words
The method of claim 16 wherein said volatile liquid is an aqueous liquid and the surface area of the resulting coated mesh is at least about 250 cm 2 /g.
Claim 22
Dependent Claim
22 words
The method of claim 17 wherein the surface area of the resulting coated mesh is at least about 350 cm 2 /g.
Claim 23
Dependent Claim
22 words
The method of claim 18 wherein the surface area of the resulting coated mesh is at least about 500 cm 2 /g.
References Cited (Backward Citations)
US971149A
Cited
US2865785A
Cited
GB998455A
Cited
FR2133216A5
Cited
GB1365601A
Cited
FR2227048A1
Cited
GB1444978A
Cited
US3931051A
Cited
US3934055A
Cited
CA1064893A
Cited
FR2280430A1
Cited
US4009829A
Cited
DE2654913A1
Cited
US4233185A
Cited
US4171289A
Cited
US4244839A
Cited
FR2445173A1
Cited
US4375426A
Cited
US4497657A
Cited
US4576827A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-09-04 | 1993-03-06 | 1993-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-04 | 1997-03-06 | 1997-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-04 | 2001-03-06 | 2001-09-05 | $7700.00 | Window Closed / Lapsed |