Patent US2581068A successfully refreshed from Google Patents.
US2581068A
Expired / Lapsed
US
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Oxidation of dicyclic hydrocarbons
Assignee: Standard Oil Development Co
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Filing: 1948-08-12
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Granted: 1952-01-01
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Expires: 1968-08-12
Abstract
No abstract record available.
Inventors
- 👤 Leland K Beach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:47
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/16; C07C51/31; C07C51/313
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
45 words
A CATALYTIC, VAPOR PHASE PROCESS FOR THE PREPARATION OF PHTHALIC ANHYDRIDE WHICH COMPRISES OXIDIZING A PETROLEUM HYDROCARBON FRACTION OF BOILING RANGE 165-185* C. CONTAINING SUBSTANTIAL AMOUNTS OF HYDROCARBONS HAVING THE INDENE NUCLEUS IN THE PRESENCE OF A VANADIUM OXIDE CATALYST AT TEMPERATURES ABOVE 400* C.
Claim 2
Dependent Claim
45 words
A CATALYTIC, VAPOR PHASE PROCESS FOR THE PREPARATION OF PHTHALIC ANHYDRIDE WHICH COMPRISES OXIDIZING A PETROLEUM HYDROCARBON FRACTION OF BOILING RANGE 165-185* C. CONTAINING SUBSTANTIAL AMOUNTS OF HYDROCARBONS HAVING THE INDENE NUCLEUS IN THE PRESENCE OF A VANADIUM OXIDE CATALYST AT TEMPERATURES ABOVE 400* C.
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) | 1954-12-31 | 1955-07-02 | 1956-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-12-31 | 1959-07-02 | 1960-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-12-31 | 1963-07-02 | 1964-01-01 | $7700.00 | Window Closed / Lapsed |