US2900309A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Separation of aromatic compounds by extractive distillation
Assignee: California Research LLC
•
Filing: 1958-08-12
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Granted: 1959-08-18
•
Expires: 1978-08-12
Abstract
No abstract record available.
Inventors
- 👤 Ralph S Valentine
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 04:36
CPC Classifications
C; C07; C07C; C07C37/00; C07C37/68; C07C37/70; C07C37/74; C07C37/78; C07C209/00; C07C209/82; C07C209/84; C07C209/86; C07C211/00; C07C211/43; C07C211/44; C07C211/49; C07C211/50
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
38 words
A PROCESS FOR SEPARATING XYLYLENE DIAMINES FROM A MIXTURE COMPRISING SAID DIAMINES AND AROMATIC NITRILES WHICH COMPRISES SUBJECTING SAID MIXTURE TO EXTRACTIVE DISTILLATION IN THE PRESENCE OF A LIQUID ALIPHATIC POLYOL CONTAINING ONLY CARBON, HYDROGEN AND OXYGEN ATOMS,SAID
Claim 2
Dependent Claim
38 words
A PROCESS FOR SEPARATING XYLYLENE DIAMINES FROM A MIXTURE COMPRISING SAID DIAMINES AND AROMATIC NITRILES WHICH COMPRISES SUBJECTING SAID MIXTURE TO EXTRACTIVE DISTILLATION IN THE PRESENCE OF A LIQUID ALIPHATIC POLYOL CONTAINING ONLY CARBON, HYDROGEN AND OXYGEN ATOMS,SAID
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-08-17 | 1963-02-16 | 1963-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-08-17 | 1967-02-16 | 1967-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-08-17 | 1971-02-16 | 1971-08-18 | $7700.00 | Window Closed / Lapsed |