US2687341A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of cryolite
Assignee: Pennsylvania Salt Manufacturing Co
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Filing: 1952-08-30
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Granted: 1954-08-24
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Expires: 1972-08-30
Abstract
No abstract record available.
Inventors
- 👤 Mockrin Isadore
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:23
CPC Classifications
C; C01; C01F; C01F7/00; C01F7/48; C01F7/50; C01F7/54
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
88 words
THE METHOD OF MAKING SYNTHETIC CRYOLITE COMPRISING PREPARING AMMONIUM FLUORIDE BY HEATING A SUBSTANTIALLY DRY, FINELY DIVIDED MIXTURE OF FLUORSPAR AND AMMONIUM SULFATE TO A TEMPERATURE OF 300* TO 600* C., PREPARING AN AQUEOUS SOLUTION OF SAID AMMONIUM FLUORIDE, ADDING SAID AMMONIUM FLUORIDE SOLUTION TO AN AQUEOUS SOLUTION OF SODIUM SULFATE AND ALUMINUM SULFATE TO FORM A CRYOLITE PRECIPITATE AND AMMONIUM SULFATE, SEPARATING SAID CRYOLITE FROM SAID AMMONIUM SULPHATE, DRYING SAID AMMONIUM SULPHATE AND REACTING SAID AMMONIUM SULPHATE WITH FRESH AMOUNTS OF FLUORSPAR TO PRODUCE MORE AMMONIUM FLUORIDE.
Claim 2
Independent Claim
88 words
THE METHOD OF MAKING SYNTHETIC CRYOLITE COMPRISING PREPARING AMMONIUM FLUORIDE BY HEATING A SUBSTANTIALLY DRY, FINELY DIVIDED MIXTURE OF FLUORSPAR AND AMMONIUM SULFATE TO A TEMPERATURE OF 300* TO 600* C., PREPARING AN AQUEOUS SOLUTION OF SAID AMMONIUM FLUORIDE, ADDING SAID AMMONIUM FLUORIDE SOLUTION TO AN AQUEOUS SOLUTION OF SODIUM SULFATE AND ALUMINUM SULFATE TO FORM A CRYOLITE PRECIPITATE AND AMMONIUM SULFATE, SEPARATING SAID CRYOLITE FROM SAID AMMONIUM SULPHATE, DRYING SAID AMMONIUM SULPHATE AND REACTING SAID AMMONIUM SULPHATE WITH FRESH AMOUNTS OF FLUORSPAR TO PRODUCE MORE AMMONIUM FLUORIDE.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-08-23 | 1958-02-22 | 1958-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-08-23 | 1962-02-22 | 1962-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-08-23 | 1966-02-22 | 1966-08-24 | $7700.00 | Window Closed / Lapsed |