US2678900A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vitamin b12 extraction process
Assignee: Merck and Co Inc
•
Filing: 1950-08-16
•
Granted: 1954-05-18
•
Expires: 1970-08-16
Abstract
No abstract record available.
Inventors
- 👤 Robert G Denkewalter
- 👤 Robert S Malcolmson
- 👤 George B Hughey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:31
CPC Classifications
A; A61; A61K; A61K31/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
70 words
THE PROCESS THAT COMPRISES EXTRACTING AN AQUEOUS SOLUTION CONTAINING LLD AND APF ACTIVE SUBSTANCES WITH AN ORGANIC SOLVENT COMPRISING A MIXTURE OF CARBON TETRACHLORIDE AND CRESOL IN THE PROPORTION OF ABOUT 1-3:1 PARTS BY VOLUME THEREBY EFFECTING A SEPARATION OF AN ORGANIC SOLVENT SOLUTION OF THE LLD AND APF ACTIVE SUBSTANCES FROM AN AQUEOUS SOLUTION OF IMPURTIES, AND RECOVERING THE LLD AND APF ACTIVE SUBSTANCES FROM SAID ORGANIC SOLVENT SOLUTION.
Claim 2
Dependent Claim
70 words
THE PROCESS THAT COMPRISES EXTRACTING AN AQUEOUS SOLUTION CONTAINING LLD AND APF ACTIVE SUBSTANCES WITH AN ORGANIC SOLVENT COMPRISING A MIXTURE OF CARBON TETRACHLORIDE AND CRESOL IN THE PROPORTION OF ABOUT 1-3:1 PARTS BY VOLUME THEREBY EFFECTING A SEPARATION OF AN ORGANIC SOLVENT SOLUTION OF THE LLD AND APF ACTIVE SUBSTANCES FROM AN AQUEOUS SOLUTION OF IMPURTIES, AND RECOVERING THE LLD AND APF ACTIVE SUBSTANCES FROM SAID ORGANIC SOLVENT SOLUTION.
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) | 1957-05-17 | 1957-11-16 | 1958-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-05-17 | 1961-11-16 | 1962-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-05-17 | 1965-11-16 | 1966-05-18 | $7700.00 | Window Closed / Lapsed |