Patent US2625554A successfully refreshed from Google Patents.
US2625554A
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Manufacture of maleic anhydride
Assignee: Monsanto Chemicals Ltd
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Filing: 1949-07-01
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Granted: 1953-01-13
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Expires: 1969-07-01
Abstract
No abstract record available.
Inventors
- 👤 Joseph R Darby
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:58
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/16; B01J23/20; B01J23/22; C; C07; C07C; C07C51/00; C07C51/16; C07C51/31; C07C51/313
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
121 words
A PROCESS WHICH COMPRISES CATALYTICALLY OXIDIZING BENZENE TO MALEIC ANHYDRIDE BY PASSING A MIXTURE OF BENZENE AND OXYGEN THROUGH A BED OF CATALYTIC PARTICLES COMPRISING A POROUS, INERT CARRIER BODY COMPOSED OF FINELY DIVIDED SILICA, THE PARTICLES OF WHICH ARE BONDED TOGETHER BY FINELY DIVIDED PARTICLES OF A REFRACTORY GLASS WHICH IS LOW IN BASIC CONSTITUENTS, SAID CARRIER BEING IMPREGNATED WITH A CATALYTICALLY ACTIVE MATERIAL CONTAINING VANADIUM AND SUBSTANTIALLY ALL OF THE PARTICLES OF SAID BED BEING OF SUCH A SIZE AS TO BE RETAINED BY A 6 MESH SCREEN AND AT LEAST THE LAST 50% OF SAID BED CONTACTED BY THE REACTANTS BEING MADE UP SUBSTANTIALLY OF PARTICLES OF SUCH A SIZE AS TO PASS THROUGH A 4 MESH SCREEN.
Claim 2
Dependent Claim
121 words
A PROCESS WHICH COMPRISES CATALYTICALLY OXIDIZING BENZENE TO MALEIC ANHYDRIDE BY PASSING A MIXTURE OF BENZENE AND OXYGEN THROUGH A BED OF CATALYTIC PARTICLES COMPRISING A POROUS, INERT CARRIER BODY COMPOSED OF FINELY DIVIDED SILICA, THE PARTICLES OF WHICH ARE BONDED TOGETHER BY FINELY DIVIDED PARTICLES OF A REFRACTORY GLASS WHICH IS LOW IN BASIC CONSTITUENTS, SAID CARRIER BEING IMPREGNATED WITH A CATALYTICALLY ACTIVE MATERIAL CONTAINING VANADIUM AND SUBSTANTIALLY ALL OF THE PARTICLES OF SAID BED BEING OF SUCH A SIZE AS TO BE RETAINED BY A 6 MESH SCREEN AND AT LEAST THE LAST 50% OF SAID BED CONTACTED BY THE REACTANTS BEING MADE UP SUBSTANTIALLY OF PARTICLES OF SUCH A SIZE AS TO PASS THROUGH A 4 MESH SCREEN.
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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) | 1956-01-13 | 1956-07-14 | 1957-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-01-13 | 1960-07-14 | 1961-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-01-13 | 1964-07-14 | 1965-01-13 | $7700.00 | Window Closed / Lapsed |