US3689216A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of hydrogen fluoride from fluosilicic acid
Assignee: Honeywell International Inc
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Filing: 1971-04-26
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Granted: 1972-09-05
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Expires: 1991-04-26
Abstract
Abstract A PROCESS FOR PRODUCING GASEOUS ANHYDROUS HYDROGEN FLUORIDE FROM FLUOSILICIC-CONTAINING SOLUTIONS BY FORMING AN ALKALI METAL FLUOSILICATE AND REACTING SAID FLOUSILICATE WITH EXCESS H2SO4 AT TEMPERATURES BETWEEN 20* AND 100* C. TO PRODUCE GASEOUS SILICON TETRAFLUORIDE AND A FLOURIDECONTAINING BY-PRODUCT AND HEATING SAID BY-PRODUCT TO A TEMPERATURE BETWEEN 80* TO 300*C. TO OBTAIN THE HYDROGEN FLUORIDE PRODUCT.
Inventors
- 👤 Russell A Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:32
CPC Classifications
C; C01; C01B; C01B7/00; C01B7/19; C01B7/191; C01B7/193
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) | 1975-09-05 | 1976-03-06 | 1976-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-05 | 1980-03-06 | 1980-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-05 | 1984-03-06 | 1984-09-05 | $7700.00 | Window Closed / Lapsed |