Patent US2737538A successfully refreshed from Google Patents.
US2737538A
Expired / Lapsed
US
⏱️ 0.0 years remaining
2-pyrrolidone as a selective solvent for aromatic hydrocarbons
Assignee: Phillips Petroleum Co
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Filing: 1952-07-24
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Granted: 1956-03-06
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Expires: 1972-07-24
Abstract
No abstract record available.
Inventors
- 👤 William T Nelson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:29
CPC Classifications
C; C10; C10G; C10G21/00; C10G21/06; C10G21/12; C10G21/20; C07; C07C; C07C7/00; C07C7/04; C07C7/05; C07C7/08; C07C7/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
30 words
IN THE SEPARATION AND RECOVERY OF AROMATIC HYDROCARBONS FROM A MIXTURE OF HYDROCARBONS INCLUDING AROMATIC AND PARAFFINIC HYDROCARBONS, THE STEP OF TREATING SAID MIXTURE WITH 2-PYRROLIDONE AS A SELECTIVE SOLVENT.
Claim 2
Dependent Claim
30 words
IN THE SEPARATION AND RECOVERY OF AROMATIC HYDROCARBONS FROM A MIXTURE OF HYDROCARBONS INCLUDING AROMATIC AND PARAFFINIC HYDROCARBONS, THE STEP OF TREATING SAID MIXTURE WITH 2-PYRROLIDONE AS A SELECTIVE SOLVENT.
References Cited (Backward Citations)
GB441104A
Cited
US2149322A
Cited
US2092739A
Cited
GB472767A
Cited
US2409059A
Cited
US2407997A
Cited
US2444582A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-03-06 | 1959-09-05 | 1960-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-03-06 | 1963-09-05 | 1964-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-03-06 | 1967-09-05 | 1968-03-06 | $7700.00 | Window Closed / Lapsed |