US4510262A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Doubly promoted catalyst with high geometric surface area
Assignee: WR Grace and Co Conn
•
Filing: 1983-10-17
•
Granted: 1985-04-09
•
Expires: 2003-10-17
Abstract
Abstract An extrudate catalyst suitable for auto emission control is made from a solid, transitional aluminia with a partially hollow interior. Deposited on the extrudate are two promoters, ceria and an alkali metal, and one or more platinum group metals. The preferred alkali metal is in the oxide form as lithia. The cylindrical extrudate has internal reinforcing vanes or ribs extending from the inner wall to the center of the extrudate particle. This configuration permits the catalyst to have the large geometric surface area per reactor volume yet, because of the openings inside the extrudate, the catalyst particles do not exhibit a large pressure drop when packed in a deep bed. These catalysts provide greater hydrocarbon and carbon monoxide conversions than do similar size spherical particles and they have improved light-off characteristics.
Inventors
- 👤 Gwan Kim
- 👤 Carmo J. Pereira
- 👤 Louis Hegedus
- 👤 James M. Maselli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 03:37
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9445; B01D53/945; B01D53/9454; B01J; B01J23/00; B01J23/38; B01J23/54; B01J23/56; B01J23/64; B01J23/656; B01J23/6562; B01J35/00; B01J35/30; B01J35/31; B01J35/32; B01J35/50; B01J35/51; B01J35/55; B01J35/60; B01J35/61; B01J35/613; B01J35/615; B01J35/63; B01J35/633; B01J35/635; B01J37/00; B01J37/0009; F; F01; F01N; F01N3/00; F01N3/08; F01N3/10; F01N3/24; F01N3/28; F01N3/2803; F01N3/2825; F01N3/2828; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
154 words
A catalyst suitable for auto emission control comprising a solid, transitional alumina extrudate support structure having a cylindrical, hollow annular configuration with internal reinforcing vanes, a nitrogen surface area of at least 50 m 2 /g; a diameter of up to about 6.5 mm; an aspect ratio of the length to the diameter of from about 1 to 5; a geometric surface area of at least 25% greater than a hollow tube of the same inside and outside diameter; a porosity of at least 0.3 cm 3 /g; a surface area per reactor volume of at least 5 cm 2 /cm 3 and deposited directly on the support structure without having any washcoat present from about 1-10 wt. % ceria, an alkali metal promoter expressed as the wt. % of the oxide M 2 O in an effective amount up to about 5% and a catalytically-effective amount of one or more platinum group metals.
Claim 2
Dependent Claim
154 words
A catalyst suitable for auto emission control comprising a solid, transitional alumina extrudate support structure having a cylindrical, hollow annular configuration with internal reinforcing vanes, a nitrogen surface area of at least 50 m 2 /g; a diameter of up to about 6.5 mm; an aspect ratio of the length to the diameter of from about 1 to 5; a geometric surface area of at least 25% greater than a hollow tube of the same inside and outside diameter; a porosity of at least 0.3 cm 3 /g; a surface area per reactor volume of at least 5 cm 2 /cm 3 and deposited directly on the support structure without having any washcoat present from about 1-10 wt. % ceria, an alkali metal promoter expressed as the wt. % of the oxide M 2 O in an effective amount up to about 5% and a catalytically-effective amount of one or more platinum group metals.
Claim 3
Dependent Claim
19 words
A catalyst according to claim 1, wherein the number of internal reinforcing vanes meeting in the center is 4.
Claim 4
Dependent Claim
19 words
A catalyst according to claim 1, wherein the number of internal reinforcing vanes meeting in the center is 6.
Claim 5
Dependent Claim
17 words
A catalyst according to claim 1, wherein the surface area is at least 100 m 2 /g.
Claim 6
Dependent Claim
22 words
A catalyst according to claim 1, wherein the surface area per reactor volume is at least 20 cm 2 /cm 3 .
Claim 7
Dependent Claim
16 words
A catalyst according to claim 1, wherein the porosity is at least 0.5 cm 3 /g.
Claim 8
Dependent Claim
16 words
A catalyst according to claim 1, wherein the aspect ratio is from about 1 to 2.
Claim 9
Dependent Claim
25 words
A catalyst according to claim 1, wherein the ratio of the wall thickness of the cylinder to the diameter is from about 0.1 to 0.3.
Claim 10
Dependent Claim
25 words
A catalyst according to claim 8, wherein the ratio of the wall thickness of the cylinder to the diameter is from about 0.07 to 0.20.
Claim 11
Dependent Claim
26 words
The catalyst according to claim 1, wherein the alkali metal is lithium and the amount of lithia deposited is about 0.5-3 wt. % Li 2 O.
Claim 12
Dependent Claim
20 words
The catalyst according to claim 1, wherein the amount of ceria deposited is about 2-6 wt. % CeO 2 .
Claim 13
Dependent Claim
34 words
A catalyst according to claim 1, wherein the platinum group metals comprise from about 1 to about 15 wt. % rhodium and from about 85 to 99 wt. % platinum, palladium or mixtures thereof.
Claim 14
Dependent Claim
19 words
The catalyst according to claim 1, wherein the platinum group metals are provided in the form of sulfito complexes.
References Cited (Backward Citations)
US2408164A
Cited
US3907710A
Cited
US3966644A
Cited
US3932309A
Cited
US4089941A
Cited
US4233187A
Cited
US4369132A
Cited
US4394303A
Cited
US4391740A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-04-08 | 1988-10-08 | 1989-04-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-04-08 | 1992-10-08 | 1993-04-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-04-08 | 1996-10-08 | 1997-04-09 | $7700.00 | Window Closed / Lapsed |