US2925431A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cationic exchange process for the separation of rare earths
Assignee: Individual
•
Filing: 1956-04-17
•
Granted: 1960-02-16
•
Expires: 1976-04-17
Abstract
No abstract record available.
Inventors
- 👤 Gregory R Choppin
- 👤 Stanley G Thompson
- 👤 Bernard G Harvey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:24
CPC Classifications
C; C22; C22B; C22B3/00; C22B3/20; C22B3/42; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
51 words
IN A PROCESS FOR SEPARATING LANTHANIDE AND ACTINIDE METAL VALUES THE STEPS COMPRISING PRODUCING AN ADSORBATE OF SAID VALUES IN A TRIVALENT OXIDATION STATE IN A CATIONIC EXCHANGE RESIN COLUMN, AND SELECTIVELY ELUTING SAID VALUES FROM THE RESIN COLUMN BY CONTACT WITH AN ACIDIC AQUEOUS SOLUTION OF AMMONIUM ALPHA HYDROXY ISOBUTYRATE.
Claim 2
Dependent Claim
51 words
IN A PROCESS FOR SEPARATING LANTHANIDE AND ACTINIDE METAL VALUES THE STEPS COMPRISING PRODUCING AN ADSORBATE OF SAID VALUES IN A TRIVALENT OXIDATION STATE IN A CATIONIC EXCHANGE RESIN COLUMN, AND SELECTIVELY ELUTING SAID VALUES FROM THE RESIN COLUMN BY CONTACT WITH AN ACIDIC AQUEOUS SOLUTION OF AMMONIUM ALPHA HYDROXY ISOBUTYRATE.
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) | 1963-02-15 | 1963-08-17 | 1964-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-02-15 | 1967-08-17 | 1968-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-02-15 | 1971-08-17 | 1972-02-16 | $7700.00 | Window Closed / Lapsed |