Patent US3687844A successfully refreshed from Google Patents.
US3687844A
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US
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Assignee: GEA Group AG
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Filing: 1970-11-25
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Granted: 1972-08-29
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Expires: 1990-11-25
Abstract
Abstract THE AQUEOUS REFINING PHASE FROM A SOLVENT EXTRACTION STEP OF A MINERAL WET PROCESSING PROCESS IS PURIFIED OF EXTRACTION AGENT REDIDUES BY PASSING THE AQUEOUS REFINING PHASE THROUGH A GRANULATED LAYER OF HYDROPHOBIC MATERIAL HAVING ACID SURFACE ACTION INTO A SEDIMENTATION CHAMBER AND WITHDRAWING THE THUS PURIFIED REFINING PHASE FROM BELOW.
Inventors
- 👤 Karl Grob
- 👤 Josef Oertter
- 👤 Paul Wiesner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:16
CPC Classifications
B; B01; B01D; B01D11/00; B01D11/04; B01D11/0492; C; C22; C22B; C22B3/00; C22B3/20; C22B3/22; C22B3/24; Y; Y02; Y02P; Y02P10/00; Y02P10/20; Y10; Y10S; Y10S423/00; Y10S423/09; Y10S423/14
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) | 1975-08-29 | 1976-02-28 | 1976-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-29 | 1980-02-28 | 1980-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-29 | 1984-02-28 | 1984-08-29 | $7700.00 | Window Closed / Lapsed |