US3579295A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for attack of bauxite with alkaline solution
Assignee: Pechiney SA
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Filing: 1968-03-15
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Granted: 1971-05-18
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Expires: 1988-03-15
Abstract
Abstract A PROCESS FOR THE CONTINUOUS ATTACK OF ORES CONTAINING ALUMINA WITH AN AQUEOUS SOLUTION OF CAUSTIC SODA AND SODIUM ALUMINATE IN WHICH USE IS MADE OF A SERIES OF STAGES EACH HAVING AN AUTOCLAVE WITH THE AUTOCLAVES INCREASING IN TEMPERATURE FROM STAGE TO STAGE IN THE DIRECTION OF FLOW OF THE SUSPENSION WITH THE AUTOCLAVE IN ONE STAGE RECEIVING SUSPENSION FROM THE PRECEDING STAGE AND EXPANSION VESSELS WITH THE EXPANSION VESSELS DECREASING IN PRESSURE IN COUNTERCURRENT RELATION WITH THE AUTOCLAVES OF INCREASING TEMPERATURE.
Inventors
- 👤 Louis Tamise
- 👤 Jacques Millet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:54
CPC Classifications
C; C01; C01F; C01F7/00; C01F7/02; C01F7/04; C01F7/06; C01F7/062
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) | 1974-05-17 | 1974-11-16 | 1975-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-17 | 1978-11-16 | 1979-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-17 | 1982-11-16 | 1983-05-18 | $7700.00 | Window Closed / Lapsed |