US3733388A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification process for solutions containing rhenium
Assignee: WC Heraus GmbH and Co KG
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Filing: 1971-04-27
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Granted: 1973-05-15
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Expires: 1991-04-27
Abstract
Abstract METAL IMPURTIES ARE QUANTITATIVELY REMOVED FROM AQUEOUS RHENIUM SOLUTION OR AN AMMONIUM PERRHENATE SOLUTION WITH AN ION EXCHANGE MATERIAL COMPRISING A SUPPORT TO WHICH IS BOUND POLYETHYLENEIMINE AS THE ACTIVE XCHANGE MATERIAL.
Inventors
- 👤 M Ziegler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:43
CPC Classifications
B; B01; B01J; B01J41/00; B01J41/04; C; C01; C01G; C01G47/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-14 | 1976-11-13 | 1977-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-14 | 1980-11-13 | 1981-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-14 | 1984-11-13 | 1985-05-15 | $7700.00 | Window Closed / Lapsed |