Patent US3674466A successfully refreshed from Google Patents.
US3674466A
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Removal of copper from aqueous solutions with highly stressed,activated ferrous metals
Assignee: Sybron Transition Corp
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Filing: 1970-05-18
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Granted: 1972-07-04
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Expires: 1990-05-18
Abstract
Abstract THE REMOVAL OF COPPER FROM AQUEOUS COPPER-CONTAINING SOLUTIONS IS ACCOMPLISHED BY PASSING AN AQUEOUS COPPER-CONTAINING SOLUTION AT A PH OF ABOUT 6.5 TO 10.5 THROUGH A COLUMN CONTAINING A HIGHLY STRESSED FORM OF FERROUS METAL WHICH HAS BEEN ACTIVATED BY TREATMENT FIRST WITH A DEGREASING AGENT AND THEN WITH AN INORGANIC ACID. A FERROUS METAL COMPLEXING AGENT ADDED TO THE AQUEOUS COPPER-CONTAINING SOLUTION PRIOR TO PASSAGE THROUGH THE COLUMN OF METAL PREVENTS FERROUS ION PRECIPITATION IN THE TREATED SOLUTION.
Inventors
- 👤 John Ray Anderson
- 👤 Richard Peck Hollingworth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 16:19
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/58; C02F1/62; C22; C22B; C22B15/00; C22B15/0063; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-04 | 1976-01-03 | 1976-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-04 | 1980-01-03 | 1980-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-04 | 1984-01-03 | 1984-07-04 | $7700.00 | Window Closed / Lapsed |