US2573282A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of artificial cryolite free from silica
Assignee: Montedison SpA
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Filing: 1948-02-27
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Granted: 1951-10-30
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Expires: 1968-02-27
Abstract
No abstract record available.
Inventors
- 👤 Sciacca Franco
- 👤 Notarbartolo Luigi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:25
CPC Classifications
C; C01; C01F; C01F7/00; C01F7/48; C01F7/50; C01F7/54
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
80 words
METHOD OF PRODUCING ARTIFICIAL CRYOLITE BY REACTION BETWEEN AN IMPURE SOLUTUION OF SODIUM FLUORIDE CONTAINING SILICA AND A SOLUTION OF ALUMINUM FLORIDE, IN WHICH METHOD THE SODIUM FLUORIDE SOLUTION CONTAINING THE SILICA AS AN IMPURITY IS FIRST ACIDIFIED TO A PH VALUE OF ABOUT 3.5 AND THEN THE TWO SOLUTIONS ARE ADMIXED WITH EACH OTHER TO CAUSE REACTION BETWEEN THEM, WITH PRODUCTION AND PRECIPITATION OF SOLID CROLITE, AND THE CRYOLITE IS THEN REMOVED AS A PREVIPITATE SUBSTANTIALLY FREE OF SILICA.
Claim 2
Dependent Claim
80 words
METHOD OF PRODUCING ARTIFICIAL CRYOLITE BY REACTION BETWEEN AN IMPURE SOLUTUION OF SODIUM FLUORIDE CONTAINING SILICA AND A SOLUTION OF ALUMINUM FLORIDE, IN WHICH METHOD THE SODIUM FLUORIDE SOLUTION CONTAINING THE SILICA AS AN IMPURITY IS FIRST ACIDIFIED TO A PH VALUE OF ABOUT 3.5 AND THEN THE TWO SOLUTIONS ARE ADMIXED WITH EACH OTHER TO CAUSE REACTION BETWEEN THEM, WITH PRODUCTION AND PRECIPITATION OF SOLID CROLITE, AND THE CRYOLITE IS THEN REMOVED AS A PREVIPITATE SUBSTANTIALLY FREE OF SILICA.
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) | 1954-10-29 | 1955-04-30 | 1955-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-10-29 | 1959-04-30 | 1959-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-10-29 | 1963-04-30 | 1963-10-30 | $7700.00 | Window Closed / Lapsed |