US3700581A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cryolitic vat for the production of aluminum by electrolysis
Assignee: Montedison SpA
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Filing: 1970-03-17
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Granted: 1972-10-24
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Expires: 1990-03-17
Abstract
Abstract DISCLOSED ARE MONOCELL AND MULTICELL FURNACES FOR FUSED BATH ELECTROLYSIS OF ALUMINA (AL2O3) DISSOLVED IN MOLTEN FLUORIDE BATHS. THE INVENTION IS CHARACTERIZED BY AN INTERNAL VAT CONSTITUTED ENTIRELY OR PARTIALLY OF SUBSTANTIALLY PURE CRYOLITE, EITHER NATURAL OR SYNTHETIC.
Inventors
- 👤 Giuseppe De Varda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:14
CPC Classifications
C; C25; C25C; C25C3/00; C25C3/06; C25C3/08; C25C3/085; C04; C04B; C04B35/00; C04B35/515
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) | 1975-10-24 | 1976-04-24 | 1976-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-24 | 1980-04-24 | 1980-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-24 | 1984-04-24 | 1984-10-24 | $7700.00 | Window Closed / Lapsed |