Patent CH307018A successfully refreshed from Google Patents.
US4412940A
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US
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Method for preparing maleic anhydride catalyst
Assignee: Huntsman Specialty Chemicals Corp
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Filing: 1980-12-18
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Granted: 1983-11-01
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Expires: 2000-12-18
Abstract
Abstract An improvement in a method of preparing catalysts for the manufacture of maleic anhydride by oxidizing a saturated hydrocarbon. The catalyst is prepared by a process in which a catalyst precursor, containing tetravalent vanadium, is formed into agglomerates and calcined, the improvement being calcining the catalyst precursor at 325°-375° C. in the presence of oxygen and a saturated aliphatic hydrocarbon.
Inventors
- 👤 Ramon A. Mount
- 👤 Harold Raffelson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:07
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/16; C07C51/31; C07C51/313; B; B01; B01J; B01J23/00; B01J23/002; B01J27/00; B01J27/14; B01J27/186; B01J27/195; B01J27/198; C07C51/21; C07C51/215; B01J2523/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
101 words
In a method for the preparation of a phosphorus-vanadium-oxygen-containing complex catalyst comprising: (a) contacting vanadium and phosphorus compounds under conditions which will provide a catalyst precursor wherein greater than 50 atom % of the vanadium is in the tetravalent state; (b) recovering the catalyst precursor; (c) forming the catalyst precursor into agglomerates; and (d) calcining the catalyst precursor agglomerations at a temperature between about 300° C. and 600° C. the improvement consisting essentially of calcining in one temperature range at 325°-375° C. the catalyst precursor in the presence of a 0.1-1.5 mole percent concentration of a saturated aliphatic hydrocarbon in air.
Claim 2
Dependent Claim
101 words
In a method for the preparation of a phosphorus-vanadium-oxygen-containing complex catalyst comprising: (a) contacting vanadium and phosphorus compounds under conditions which will provide a catalyst precursor wherein greater than 50 atom % of the vanadium is in the tetravalent state; (b) recovering the catalyst precursor; (c) forming the catalyst precursor into agglomerates; and (d) calcining the catalyst precursor agglomerations at a temperature between about 300° C. and 600° C. the improvement consisting essentially of calcining in one temperature range at 325°-375° C. the catalyst precursor in the presence of a 0.1-1.5 mole percent concentration of a saturated aliphatic hydrocarbon in air.
Claim 3
Dependent Claim
13 words
The method improvement of claim 1 wherein the saturated aliphatic hydrocarbon is butane.
Claim 4
Dependent Claim
13 words
The method improvement of claim 1 wherein temperature of calcination is 345°-360° C.
Claim 5
Dependent Claim
14 words
The method improvement of claim 1 wherein temperature of calcination is about 350° C.
Claim 6
Dependent Claim
17 words
The method improvement of claim 2 wherein the concentration of butane in air is 0.8-1.2 mole percent.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-10-31 | 1987-05-02 | 1987-11-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-31 | 1991-05-02 | 1991-11-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-31 | 1995-05-02 | 1995-11-01 | $7700.00 | Window Closed / Lapsed |