US3725261A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Removal of mercury from liquids using keratin derivatives
Assignee: United States Department of Agriculture
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Filing: 1971-11-05
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Granted: 1973-04-03
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Expires: 1991-11-05
Abstract
Abstract MERCURY IS EFFECTIVELY REMOVED FROM WATER OR OTHER LIQUIDS BY CONTACT WITH A KERATIN DERIVATIVE, E.G., REACTION PRODUCTS OF REDUCED WOOL WITH N-VINYLIMIDAZOLE, N-VINYLPYRROLIDONE, OR 2-VINYLPYRIDINE.
Inventors
- 👤 M Friedman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:48
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/28; C02F1/285
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) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |