Patent US2537115A successfully refreshed from Google Patents.
US2537115A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Extractive distillation of alcohols
Assignee: F Hoffmann La Roche AG
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Filing: 1948-07-23
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Granted: 1951-01-09
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Expires: 1968-07-23
Abstract
No abstract record available.
Inventors
- 👤 Scheilbel Edward George
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:41
CPC Classifications
C; C07; C07C; C07C29/00; C07C29/74; C07C29/76; C07C29/80; C07C29/84
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
77 words
A PROCESS OF SEPARATING A MIXTURE OF TWO OR MORE SATURATED UNSUBSTITUTED ALIPHATIC ALCOHOLS CONTAINING NOT MORE THAN FOUR CARBON ATOMS AND HAVING CLOSELY RELATED BOILING POINTS WHICH COMPRISES EXTRACTIVELY DISTILLING THE MIXTURE IN THE PRESENCE OF A SOLVENT SELECTED FROM THE GROUP CONSISTING OF METHYL-ISOBUTYL-KETONE AND KETONES BOILING HIGHER THAN METHYL-ISOBUTYL-KETONE, WHICH SOLVENT HAS A BOILING POINT SUFFICIENTLY ABOVE THAT OF THE HIGHEST BOILING ALCOHOL IN THE MIXTURE THAT IT DOES NOT FORM AN AZEOTROPE THEREWITH.
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) | 1954-01-08 | 1954-07-10 | 1955-01-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-01-08 | 1958-07-10 | 1959-01-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-01-08 | 1962-07-10 | 1963-01-09 | $7700.00 | Window Closed / Lapsed |