US2925325A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the manufacture of cryolite
Assignee: Reynolds Metals Co
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Filing: 1958-02-17
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Granted: 1960-02-16
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Expires: 1978-02-17
Abstract
No abstract record available.
Inventors
- 👤 Kamlet Jonas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 01:47
CPC Classifications
C; C01; C01F; C01F7/00; C01F7/48; C01F7/50; C01F7/54
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
135 words
A PROCESS FOR THE MANUFACTURE OF CRYLOLITE WHICH COMPRISES THE STEPS OF: (A) REACTING AN SOLUTION CONTAINING FLUOBORIC ACID WITH A DOUBLE SALT OF COMPOSITION NA2SO4.NAF AND A MEMBER OF THE GROUP CONSISTING OF ALUMINUM HYDROXIDE AND ALUMINUM OXIDE, (B) SEPARATING THE PRECIPITATE OF CRYOLITE FROM THE SOLUTION OF BORIC ACID AND SULFURIC ACID, (C) REACTING SAID SOLUTION OF BORIC ACID AND SULFURIC ACID WITH A CALCIUM FLUORIDE-CONTAINING MATERIAL AND AT LEAST ONE MEMBER OF THE GROUP CONSISTING OF HYDROGEN FLUORIDE, SILICON TETRAFLUORIDE AND FLUOSILICIC ACID IN QUANTITY SUFFICIENT TO FORM AN AMOUNT OF FLUOBORIC ACID EQUIVALENT TO THE QUANTITY EMPLOYED IN STEP (A) AND A PRECIPITATE OF CALCIUM SULFATE, AND (D) SEPARATING THE CALCIUM SULFATE FROM THE SOLUTION OF FLUOBORIC ACID AND RETURNING SAID SOLUTION OF FLUOBORIC ACID TO STEP (A) OIF THE PROCESS.
Claim 2
Dependent Claim
135 words
A PROCESS FOR THE MANUFACTURE OF CRYLOLITE WHICH COMPRISES THE STEPS OF: (A) REACTING AN SOLUTION CONTAINING FLUOBORIC ACID WITH A DOUBLE SALT OF COMPOSITION NA2SO4.NAF AND A MEMBER OF THE GROUP CONSISTING OF ALUMINUM HYDROXIDE AND ALUMINUM OXIDE, (B) SEPARATING THE PRECIPITATE OF CRYOLITE FROM THE SOLUTION OF BORIC ACID AND SULFURIC ACID, (C) REACTING SAID SOLUTION OF BORIC ACID AND SULFURIC ACID WITH A CALCIUM FLUORIDE-CONTAINING MATERIAL AND AT LEAST ONE MEMBER OF THE GROUP CONSISTING OF HYDROGEN FLUORIDE, SILICON TETRAFLUORIDE AND FLUOSILICIC ACID IN QUANTITY SUFFICIENT TO FORM AN AMOUNT OF FLUOBORIC ACID EQUIVALENT TO THE QUANTITY EMPLOYED IN STEP (A) AND A PRECIPITATE OF CALCIUM SULFATE, AND (D) SEPARATING THE CALCIUM SULFATE FROM THE SOLUTION OF FLUOBORIC ACID AND RETURNING SAID SOLUTION OF FLUOBORIC ACID TO STEP (A) OIF THE PROCESS.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-02-15 | 1963-08-17 | 1964-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-02-15 | 1967-08-17 | 1968-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-02-15 | 1971-08-17 | 1972-02-16 | $7700.00 | Window Closed / Lapsed |