US4132669A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing phosphorous-alumina catalysts using polycarboxylic acids as extrusion aids
Assignee: CROSFIELD CHEMICALS COMPANY A DIVISION OF INDOPCO Inc A CORP OF DELAWARE
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Filing: 1977-10-06
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Granted: 1979-01-02
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Expires: 1997-10-06
Abstract
Abstract Alumina-phosphorous powders can be extruded into catalysts supports having improved properties by the addition of up to 15% by weight of a polycarboxylic acid, containing 2-10 carbon atoms, based on the dry weight of the alumina-phosphorous powder prior to extrusion. The addition of the polycarboxylic acid also increases the extrusion rate.
Inventors
- 👤 Monica E. Choca
- 👤 Gerald R. Feistel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:56
CPC Classifications
B; B01; B01J; B01J27/00; B01J27/14; B01J27/16; B01J37/00; B01J37/0009
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
120 words
A process for preparing phospha-alumina extrudates having a relatively high crush strength, and relatively reduced pore volume in pores above 600 A diameter comprising: A. preparing a purified phospha-alumina powder comprising on a dry basis 3-30% P 2 O 5 and 70-97% Al 2 O 3 . B. mixing said purified phospha-alumina powder with water and from 0.1-15% by weight of a water-soluble polycarboxylic acid containing from 1-10 carbon atoms based on the dry weight of the powder. C. adjusting the moisture content of said phospha-alumina powder to an extrudate level so as to allow extrusion; and then, D. extruding said phospha-alumina powder to prepare a phospha-alumina extrudate whereby the extrusion rate is improved over phospha-alumina powders not so treated.
Claim 2
Dependent Claim
120 words
A process for preparing phospha-alumina extrudates having a relatively high crush strength, and relatively reduced pore volume in pores above 600 A diameter comprising: A. preparing a purified phospha-alumina powder comprising on a dry basis 3-30% P 2 O 5 and 70-97% Al 2 O 3 . B. mixing said purified phospha-alumina powder with water and from 0.1-15% by weight of a water-soluble polycarboxylic acid containing from 1-10 carbon atoms based on the dry weight of the powder. C. adjusting the moisture content of said phospha-alumina powder to an extrudate level so as to allow extrusion; and then, D. extruding said phospha-alumina powder to prepare a phospha-alumina extrudate whereby the extrusion rate is improved over phospha-alumina powders not so treated.
Claim 3
Dependent Claim
12 words
The process of claim 1 where the polycarboxylic acid is citric acid.
Claim 4
Dependent Claim
18 words
The process of claim 1 wherein the phospha-alumina extrudate is dried and calcined to prepare a catalyst support.
Claim 5
Dependent Claim
20 words
The process of claim 1 where the crush strength is increased by at least 25% over non-polycarboxylic acid treated material.
Claim 6
Dependent Claim
25 words
The process of claim 1 where pore volume above 600 A of the product is decreased relative to that where no polycarboxylic acid is used.
Claim 7
Dependent Claim
20 words
The process of claim 1 where the shrinkage on calcination is increased over that where no polycarboxylic acid is used.
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) | 1982-01-01 | 1982-07-03 | 1983-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-01-01 | 1986-07-03 | 1987-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-01-01 | 1990-07-03 | 1991-01-02 | $7700.00 | Window Closed / Lapsed |