Patent US2921678A successfully refreshed from Google Patents.
US2921678A
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Novel flotation process
Assignee: Columbia Southern Chemical Corp
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Filing: 1957-02-19
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Granted: 1960-01-19
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Expires: 1977-02-19
Abstract
No abstract record available.
Inventors
- 👤 Charles H Fuchsman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:57
CPC Classifications
C; C01; C01D; C01D3/00; C01D3/04; C01D3/08; B; B03; B03D; B03D1/00; B03D1/001; B03D1/004; B03D1/01; C11; C11D; C11D13/00; C11D13/02; C11D13/04; B03D1/011; B03D2201/00; B03D2201/02; B03D2203/00; B03D2203/02; B03D2203/04; B03D2203/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
53 words
A METHOD OF RECOVERING POTASSIUM CHLORIDE FROM ORES THEREOF CONTAINING FROM 1 TO 10 PERCENT CALCIUM SULFATE BY WEIGHT BY FROTH FLOTATION WHICH COMPRISES SUSPENDING THE ORE IN AN AQUEOUS SLURRY, ACIDIFYING THE SLURRY TO A PH BELOW 4, INCLUDING A CATIONIC FROTH FLOTATION AGENT IN THE ACIDIFIED SLURRY AND EFFECTING FROTH FLOTATION.
Claim 2
Independent Claim
53 words
A METHOD OF RECOVERING POTASSIUM CHLORIDE FROM ORES THEREOF CONTAINING FROM 1 TO 10 PERCENT CALCIUM SULFATE BY WEIGHT BY FROTH FLOTATION WHICH COMPRISES SUSPENDING THE ORE IN AN AQUEOUS SLURRY, ACIDIFYING THE SLURRY TO A PH BELOW 4, INCLUDING A CATIONIC FROTH FLOTATION AGENT IN THE ACIDIFIED SLURRY AND EFFECTING FROTH FLOTATION.
References Cited (Backward Citations)
US2633241A
Cited
US2721657A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-01-18 | 1963-07-20 | 1964-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-01-18 | 1967-07-20 | 1968-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-01-18 | 1971-07-20 | 1972-01-19 | $7700.00 | Window Closed / Lapsed |