Patent US2916494A successfully refreshed from Google Patents.
US2916494A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of j-pyridine carboxylic acid
Assignee: —
•
Filing: —
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Granted: 1959-12-08
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Expires: 1976-12-08
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 23:19
CPC Classifications
C; C07; C07D; C07D213/00; C07D213/02; C07D213/04; C07D213/60; C07D213/78; C07D213/79; C07D213/803; A; A61; A61K; A61K31/00; A61K31/33; A61K31/395; A61K31/435; A61K31/44; A61K31/455
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
85 words
METHOD OF SEPARATING NICOTINIC ACID MADE BY OXIDATION PROCESS FROM ADMIXED ORGANIC IMPURITIES AND INORGANIC SALTS BY SUBLIMATION COMPRISING PASSING AN INERT GAS COMPRISING STEAM OVER SAID NICOTINIC ACID IN AN AMOUNT OF 1 POUND MOL OF GAS PER0.005-0.02 POUND MOL OF NICOTINIC ACID AT A TEMPERATURE OF 160-250* C., TO ENTRAIN NICOTINIC ACID VAPORS IN SAID GAS, CONTACTING SAID GAS CONTAINING SAID NICOTINIC ACID VAPORS WITH WATER TO FORM AN AQUEOUS SLURRY OF NICOTINIC ACID, AND RECOVERING SUBSTANTIALLY PURE NICOTININ ACID FROM SAID SLURRY.
Claim 2
Dependent Claim
85 words
METHOD OF SEPARATING NICOTINIC ACID MADE BY OXIDATION PROCESS FROM ADMIXED ORGANIC IMPURITIES AND INORGANIC SALTS BY SUBLIMATION COMPRISING PASSING AN INERT GAS COMPRISING STEAM OVER SAID NICOTINIC ACID IN AN AMOUNT OF 1 POUND MOL OF GAS PER0.005-0.02 POUND MOL OF NICOTINIC ACID AT A TEMPERATURE OF 160-250* C., TO ENTRAIN NICOTINIC ACID VAPORS IN SAID GAS, CONTACTING SAID GAS CONTAINING SAID NICOTINIC ACID VAPORS WITH WATER TO FORM AN AQUEOUS SLURRY OF NICOTINIC ACID, AND RECOVERING SUBSTANTIALLY PURE NICOTININ ACID FROM SAID SLURRY.
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) | 1962-12-07 | 1963-06-08 | 1963-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-12-07 | 1967-06-08 | 1967-12-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-12-07 | 1971-06-08 | 1971-12-08 | $7700.00 | Window Closed / Lapsed |