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US3043890A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of petroleum naphthalene
Assignee: Union Oil Company of California
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Filing: 1960-04-04
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Granted: 1962-07-10
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Expires: 1980-04-04
Abstract
No abstract record available.
Inventors
- 👤 Art C Mckinnis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:57
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/04; C07C7/05; C07C7/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
66 words
A METHOD FOR THE RECOVERY OF SUBSTANTIALLY PURE NAPHTHALENE FROM A PETROLEUM FRACTION BOILING ABOVE ABOUT 400*F., WHICH COMPRISES: (1) SUBJECTING SAID FRACTION TO AZEOTROPIC DISTILLATION IN ADMIXTURE WITH BUTYROLACTONE UNTIL SUBSTANTIALLY ALL THE NON-NAPHTHALENIC HYDROCARBONS IN SAID FRACTION WHICH BIOL WITHIN ABOUT 10*F. OF NAPHTHALENE ARE DISTILLED OVERHEAD AS AN AZEOTROPE WITH SAID BUTYROLACTONE, AND (2) RECOVERING SUBSTANTIALLY PURE NAPHTHALENE FROM THE REMAINING BOTTOMS FRACTION.
Claim 2
Independent Claim
66 words
A METHOD FOR THE RECOVERY OF SUBSTANTIALLY PURE NAPHTHALENE FROM A PETROLEUM FRACTION BOILING ABOVE ABOUT 400*F., WHICH COMPRISES: (1) SUBJECTING SAID FRACTION TO AZEOTROPIC DISTILLATION IN ADMIXTURE WITH BUTYROLACTONE UNTIL SUBSTANTIALLY ALL THE NON-NAPHTHALENIC HYDROCARBONS IN SAID FRACTION WHICH BIOL WITHIN ABOUT 10*F. OF NAPHTHALENE ARE DISTILLED OVERHEAD AS AN AZEOTROPE WITH SAID BUTYROLACTONE, AND (2) RECOVERING SUBSTANTIALLY PURE NAPHTHALENE FROM THE REMAINING BOTTOMS FRACTION.
References Cited (Backward Citations)
GB804221A
Cited
US2831905A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-07-09 | 1966-01-08 | 1966-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-07-09 | 1970-01-08 | 1970-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-07-09 | 1974-01-08 | 1974-07-10 | $7700.00 | Window Closed / Lapsed |