Patent US3615173A successfully refreshed from Google Patents.
US3615173A
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US
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Separation of rare earth elements by ion exchange
Assignee: LINDSTROEM ROALD E
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Filing: 1969-04-03
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Granted: 1971-10-26
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Expires: 1989-04-03
Abstract
Abstract Diethylenetriaminepentaacetic acid or hydroxyethylethylenediaminetriacetic acid is used as retaining agent in separating rare-earth elements on a cation-exchange resin column. The rare-earth metals and their compounds find a wide variety of uses such as use in special alloys, in lasers, in dielectric ceramics, in nuclear technology, in phosphors, etc.
Inventors
- 👤 J Oscar Winget
- 👤 Roald E Lindstrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:53
CPC Classifications
C; C22; C22B; C22B59/00; Y; Y10; Y10S; Y10S423/00; Y10S423/19
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
26 words
The process of claim 1 in which the resin beds are maintained at an elevated temperature sufficient to maintain the eluant and retaining-agent compounds in solution.
References Cited (Backward Citations)
US2798789A
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US3054655A
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US2956858A
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US3167389A
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US3228750A
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US3482932A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-25 | 1975-04-26 | 1975-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-25 | 1979-04-26 | 1979-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-25 | 1983-04-26 | 1983-10-26 | $7700.00 | Window Closed / Lapsed |