US2776990A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Separation of a dibasic acid from a mixture of mono and dibasic acids
Assignee: EIDP Inc
•
Filing: 1953-01-26
•
Granted: 1957-01-08
•
Expires: 1973-01-26
Abstract
No abstract record available.
Inventors
- 👤 Roger A Hines
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 18:18
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/42; C07C51/43
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
123 words
IN A PROCESS FOR THE CRYSTALLIZATION OF ADIPIC ACID FROM THE NITRIC ACID MOTHER LIQUOR OBTAINED BY CRYSTALLIZING ADIPIC ACID FROM THE MIXTURE OF MONOBASIC ACIDS AND DIBASIC ACIDS OBTAINED BY THE AIR AND NITRIC ACID OXIDATION OF CYCLIC ALKANES, SAID MOTHER LIQUOR CONTAINING A HIGHER CONCENTRATION OF SUCCINIC ACID THAN ADIPIC ACID, THE STEP WHICH COMPRISES ADDING A SUFFICIENT AMUNT OF AMMONIA TO THE MOTHER LIQUOR TO NEUTRALIZE THE NITRIC ACID AND MONOBASIC ACIDS PRESENT AND FROM 40 TO 75% OF THE CARBOXYL GROUPS OF THE SUCCINIC ACID PRESENT BUT INSUFFICIENT TO PRECIPITATE AMMONIUM SALTS DURING SUBSEQUENT CRYSTALLIZATION, AND THEREAFTER CRYSTALLIZING THE ADIPIC ACID FROM A TEMPERATURE AT WHICH ALL THE ACIDS AND SALTS PRESENT ARE IN SOLUTION IN THE MOTHER LIQUOR.
Claim 2
Dependent Claim
123 words
IN A PROCESS FOR THE CRYSTALLIZATION OF ADIPIC ACID FROM THE NITRIC ACID MOTHER LIQUOR OBTAINED BY CRYSTALLIZING ADIPIC ACID FROM THE MIXTURE OF MONOBASIC ACIDS AND DIBASIC ACIDS OBTAINED BY THE AIR AND NITRIC ACID OXIDATION OF CYCLIC ALKANES, SAID MOTHER LIQUOR CONTAINING A HIGHER CONCENTRATION OF SUCCINIC ACID THAN ADIPIC ACID, THE STEP WHICH COMPRISES ADDING A SUFFICIENT AMUNT OF AMMONIA TO THE MOTHER LIQUOR TO NEUTRALIZE THE NITRIC ACID AND MONOBASIC ACIDS PRESENT AND FROM 40 TO 75% OF THE CARBOXYL GROUPS OF THE SUCCINIC ACID PRESENT BUT INSUFFICIENT TO PRECIPITATE AMMONIUM SALTS DURING SUBSEQUENT CRYSTALLIZATION, AND THEREAFTER CRYSTALLIZING THE ADIPIC ACID FROM A TEMPERATURE AT WHICH ALL THE ACIDS AND SALTS PRESENT ARE IN SOLUTION IN THE MOTHER LIQUOR.
References Cited (Backward Citations)
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US2323061A
Cited
US2557282A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-01-08 | 1960-07-09 | 1961-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-01-08 | 1964-07-09 | 1965-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-01-08 | 1968-07-09 | 1969-01-08 | $7700.00 | Window Closed / Lapsed |