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Patent US2684322A successfully refreshed from Google Patents.
US2684322A
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Ion exchange purification of vitamin b12
Assignee: Pharmacia and Upjohn Co
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Filing: 1950-02-27
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Granted: 1954-07-20
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Expires: 1970-02-27
Abstract
No abstract record available.
Inventors
- 👤 George C Colovos
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:12
CPC Classifications
B; B01; B01J; B01J47/00; B01J47/014; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/917
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
60 words
A PROCESS FOR THE PURIFICATION AND CONCENTRATION OF VITAMIN B12 BY ADSORPTION OF IMPURITIES ON AN ION EXCHANGE RESIN WHICH COMPRISES SUBJECTING AN IMPURE AQUEOUS SOLUTION OF THE VITAMIN B12 TO CONTACT WITH FIRST A CATION EXCHANGE RESIN FOLLOWED DIRECTLY BY CONTACTING WITH AN ANION EXCHANGE RESIN, AND SUBSEQUENTLY RECOVERING THE PURIFIED VITAMIN B12-CONTAINING SOLID MATERIAL FROM THE RESULTING SOLUTION.
References Cited (Backward Citations)
US2443485A
Cited
GB450309A
Cited
US2388194A
Cited
US2407096A
Cited
US2582589A
Cited
US2563794A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-07-19 | 1958-01-18 | 1958-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-07-19 | 1962-01-18 | 1962-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-07-19 | 1966-01-18 | 1966-07-20 | $7700.00 | Window Closed / Lapsed |