US3072459A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing fluoride-free columbium or tantalum pentoxide
Assignee: Union Carbide Corp
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Filing: 1959-12-30
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Granted: 1963-01-08
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Expires: 1979-12-30
Abstract
No abstract record available.
Inventors
- 👤 Raymond A Foos
- 👤 Robert L Ripley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 14:34
CPC Classifications
C; C01; C01G; C01G33/00; C01P; C01P2006/00; C01P2006/80
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
138 words
A PROCESS FOR PRODUCING A SUBSTANTIALLY FLUORIDE-FREE PENTOXIDE OF AT LEAST ONE METAL SELECTED FROM THE GROUP CONSISTING OF COLUMBIUM AND TANTALUM FROM AN AQUEOUS HYDROFLUORIC ACID SOLUTION CONTAINING A COMPOUND SELECTED FROM THE GROUP CONSISTING OF H2CBF7, H2CBOF5 AND H2TAF7 WHICH PROCESS COMPRISES ADDING AT LEAST 2 1/2 MOLES OF SULFURIC ACID TO SAID SOLUTION FOR EVERY MOLE OF H2CBF7 AND H2TAF7 CONTAINED THEREIN AND AT LEAST 1 1/2 MOLES OF SULFURIC ACID FOR EVERY MOLE OF H2CBOF5 CONTAINED THEREIN; DIGESTING THE SO-ACIDIFIED SOLUTION BY BOILING IT WHEREBY THE COMBINED FLUORINE IS DISSOCIATED FROM THE METAL COMPOUNDS AND VOLATILIZED DURING SAID DIGESTION AS GASEOUS HYDROGEN FLUORIDE; CONTINUING SAID DIGESTION UNTIL THE EVOLUTION OF GASEOUS HYDROGEN FLUORIDE FROM SAID SOLUTION HAS SUBSTANTIALLY SUBSIDED; AND PRECIPITATING SAID SELECTED METAL FROM THE SOLUTION AS A HYDRATED PENTOXIDE OF SAID METAL.
Claim 2
Dependent Claim
138 words
A PROCESS FOR PRODUCING A SUBSTANTIALLY FLUORIDE-FREE PENTOXIDE OF AT LEAST ONE METAL SELECTED FROM THE GROUP CONSISTING OF COLUMBIUM AND TANTALUM FROM AN AQUEOUS HYDROFLUORIC ACID SOLUTION CONTAINING A COMPOUND SELECTED FROM THE GROUP CONSISTING OF H2CBF7, H2CBOF5 AND H2TAF7 WHICH PROCESS COMPRISES ADDING AT LEAST 2 1/2 MOLES OF SULFURIC ACID TO SAID SOLUTION FOR EVERY MOLE OF H2CBF7 AND H2TAF7 CONTAINED THEREIN AND AT LEAST 1 1/2 MOLES OF SULFURIC ACID FOR EVERY MOLE OF H2CBOF5 CONTAINED THEREIN; DIGESTING THE SO-ACIDIFIED SOLUTION BY BOILING IT WHEREBY THE COMBINED FLUORINE IS DISSOCIATED FROM THE METAL COMPOUNDS AND VOLATILIZED DURING SAID DIGESTION AS GASEOUS HYDROGEN FLUORIDE; CONTINUING SAID DIGESTION UNTIL THE EVOLUTION OF GASEOUS HYDROGEN FLUORIDE FROM SAID SOLUTION HAS SUBSTANTIALLY SUBSIDED; AND PRECIPITATING SAID SELECTED METAL FROM THE SOLUTION AS A HYDRATED PENTOXIDE OF SAID METAL.
References Cited (Backward Citations)
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US2819146A
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US2819945A
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US2980496A
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US2950966A
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US2953453A
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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) | 1966-01-07 | 1966-07-09 | 1967-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-01-07 | 1970-07-09 | 1971-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-01-07 | 1974-07-09 | 1975-01-08 | $7700.00 | Window Closed / Lapsed |