Patent US2920941A successfully refreshed from Google Patents.
US2920941A
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Method of selectively separating hydrofluoric acid from its solution with other hydrohalogenic acids
Assignee: Societe dElectro Chimie dElectro Metallurgie et des Acieries Electriques Dugine SA SECEMAU
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Filing: 1956-05-14
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Granted: 1960-01-12
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Expires: 1976-05-14
Abstract
No abstract record available.
Inventors
- 👤 Sanlaville Joseph
- 👤 Foulletier Louis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:32
CPC Classifications
C; C01; C01B; C01B7/00; C01B7/19; C01B7/191; C01B7/195; C01B7/197; H; H01; H01J; H01J13/00; H01J13/02; H01J2893/00; H01J2893/0072; H01J2893/0073
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
92 words
A METHOD OF SELECTIVE SEPARATION OF HYDROFLUORIC ACID FROM AN AQUEOUS SOLUTION CONTAINING HYDROFLUORIC ACID AND AT LEAST ONE OTHER HYDROHALOGENIC ACID, SAID METHOD COMPRISING CONTACTING THE SOLUTION WITH CALCINED ALUMINA WHICH IS SUBSTANTIALLY INSOLUBLE IN THE SOLUTION AND ADAPTED TO SELECTIVELY FIX A SUBSTANTIAL PORTION OF THE HYDROFLUORIC ACID FROM THE SOLUTION, SAID ALUMINA BEING FROM THE GROUP CONSISTING OF HYDRARGILLITE, ALUMINA GELS, ALUMINA HYDRATES AND AMORPHOUS ALUMINA, AND HAVING BEEN MODERATELY CALCINED AT A TEMPERATURE GREATER THAN ABOUT 1000*-1200*C., AND SEPARATING THE ALUMINA AND FIXED HYDROFLUORIC ACID FROM THE SOLUTION.
Claim 2
Independent Claim
92 words
A METHOD OF SELECTIVE SEPARATION OF HYDROFLUORIC ACID FROM AN AQUEOUS SOLUTION CONTAINING HYDROFLUORIC ACID AND AT LEAST ONE OTHER HYDROHALOGENIC ACID, SAID METHOD COMPRISING CONTACTING THE SOLUTION WITH CALCINED ALUMINA WHICH IS SUBSTANTIALLY INSOLUBLE IN THE SOLUTION AND ADAPTED TO SELECTIVELY FIX A SUBSTANTIAL PORTION OF THE HYDROFLUORIC ACID FROM THE SOLUTION, SAID ALUMINA BEING FROM THE GROUP CONSISTING OF HYDRARGILLITE, ALUMINA GELS, ALUMINA HYDRATES AND AMORPHOUS ALUMINA, AND HAVING BEEN MODERATELY CALCINED AT A TEMPERATURE GREATER THAN ABOUT 1000*-1200*C., AND SEPARATING THE ALUMINA AND FIXED HYDROFLUORIC ACID FROM THE SOLUTION.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-01-11 | 1963-07-13 | 1964-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-01-11 | 1967-07-13 | 1968-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-01-11 | 1971-07-13 | 1972-01-12 | $7700.00 | Window Closed / Lapsed |