US2574256A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of recovering crystalline cyanoacetic acid
Assignee: Individual
•
Filing: 1949-10-27
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Granted: 1951-11-06
•
Expires: 1969-10-27
Abstract
No abstract record available.
Inventors
- 👤 Alvin C Flisik
- 👤 Nicholl Leonard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:07
CPC Classifications
C; C07; C07C; C07C255/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
69 words
METHOD OF PURIFYING A MIXTURE OF CYANOACETIC ACID, ALIPHATIC KETONE AND CONTAMINANTS COMPRISING KETONE-SOLUBLE, HIGHLY COLORED IMPURITIES AND BY-PRODUCTS OF REACTION, WHICH MIXTURE IS DERIVED BY TREATING AQUEOUS BRINE SOLUTIONS OF CYANOACETIC ACID WITH SELECTIVELY HYDROPHILIC ALIPHATIC KETONES WHEREBY TO FORM A SUBSTANTIALLY ANHYDROUS KETONE SOLUTION CONTAINING SAID CYANOACETIC ACID, AND CONTAMINANTS, WHICH COMPRISES STEAM DISTILLING THE MIXTURE AND REMOVING THE KETONE FROM THE MIXTURE AS AN AQUEOUS AZETROPE.
Claim 2
Dependent Claim
69 words
METHOD OF PURIFYING A MIXTURE OF CYANOACETIC ACID, ALIPHATIC KETONE AND CONTAMINANTS COMPRISING KETONE-SOLUBLE, HIGHLY COLORED IMPURITIES AND BY-PRODUCTS OF REACTION, WHICH MIXTURE IS DERIVED BY TREATING AQUEOUS BRINE SOLUTIONS OF CYANOACETIC ACID WITH SELECTIVELY HYDROPHILIC ALIPHATIC KETONES WHEREBY TO FORM A SUBSTANTIALLY ANHYDROUS KETONE SOLUTION CONTAINING SAID CYANOACETIC ACID, AND CONTAMINANTS, WHICH COMPRISES STEAM DISTILLING THE MIXTURE AND REMOVING THE KETONE FROM THE MIXTURE AS AN AQUEOUS AZETROPE.
References Cited (Backward Citations)
US2338834A
Cited
US2480380A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-11-05 | 1955-05-07 | 1955-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-11-05 | 1959-05-07 | 1959-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-11-05 | 1963-05-07 | 1963-11-06 | $7700.00 | Window Closed / Lapsed |