Patent US3005684A successfully refreshed from Google Patents.
US3005684A
Expired / Lapsed
US
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Process for making ammonium bifluoride
Assignee: Wasag Chemie AG
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Filing: 1957-10-25
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Granted: 1961-10-24
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Expires: 1977-10-25
Abstract
No abstract record available.
Inventors
- 👤 Riedl Hans-Joachim
- 👤 Dahmlos Johannes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:03
CPC Classifications
C; C01; C01C; C01C1/00; C01C1/16; C01C1/162
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
175 words
IN A PROCESS FOR PRODUCING AMMONIUM BIFLUORIDE FROM INDUSTRIAL FLUOSILICIC ACID BY TREATMENT WITH SUFFICIENT AMMONIA TO FORM A PRECIPITATE OF SILICIC ACID AND A SOLUTION OF AMMONIUM FLUORIDE, SEPARATING SAID PRECIPITATE AND CONCENTRATING THE RESULTING AMMONIUM FLUORIDE CONTAINING SOLUTION BY DISTILLING OFF WATER AND AMMONIA, THE IMPROVEMENT COMPRISING THE STEPS OF FEEDING AN AQUEOUS SOLUTION OF AMMONIUM FLUORIDE INTO THE UPPER END OF A DISTILLATION COLUMN HEATED AT ITS LOWER END TO ABOUT 200* C., AT SUCH RATE THAT THE TEMPERATURE AT THE UPPER END OF THE COLUMN IS MAINTAINED AT ABOUT 105*C., AND THE TEMPERATURE IN THE CENTRAL ZONE OF THE COLUMN IS MAINTAINED AT ABOUT 115*C., WITHDRAWING THE RESULTING MELT OF AMMONIUM BIFLUORIDE WHICH IS PRACTICALLY FREE FROM AMMONIUM FLUORIDE, CONTINUOUSLY FROM THE LOWER END OF THE COLUMN, SOLIDIFYING THE MELT, RECRYSTALLIZING THE SOLIDIFIED CRUDE AMMONIUM BIFLUORIDE FROM WATER, AND RECYCLING THE MOTHER LIQUOR FROM THE RECRYSTALLIZATION STEP CONTINUOUSLY INTO THE COLUMN THROUGH THE TOP END THEREOF COUNTERCURRENTLY TO THE EXCESS GASES CONSISTING OF SUBLIMATING AMMONIUM BIFLUORIDE, AMMONIA AND WATER VAPORS RE-
Claim 2
Dependent Claim
175 words
IN A PROCESS FOR PRODUCING AMMONIUM BIFLUORIDE FROM INDUSTRIAL FLUOSILICIC ACID BY TREATMENT WITH SUFFICIENT AMMONIA TO FORM A PRECIPITATE OF SILICIC ACID AND A SOLUTION OF AMMONIUM FLUORIDE, SEPARATING SAID PRECIPITATE AND CONCENTRATING THE RESULTING AMMONIUM FLUORIDE CONTAINING SOLUTION BY DISTILLING OFF WATER AND AMMONIA, THE IMPROVEMENT COMPRISING THE STEPS OF FEEDING AN AQUEOUS SOLUTION OF AMMONIUM FLUORIDE INTO THE UPPER END OF A DISTILLATION COLUMN HEATED AT ITS LOWER END TO ABOUT 200* C., AT SUCH RATE THAT THE TEMPERATURE AT THE UPPER END OF THE COLUMN IS MAINTAINED AT ABOUT 105*C., AND THE TEMPERATURE IN THE CENTRAL ZONE OF THE COLUMN IS MAINTAINED AT ABOUT 115*C., WITHDRAWING THE RESULTING MELT OF AMMONIUM BIFLUORIDE WHICH IS PRACTICALLY FREE FROM AMMONIUM FLUORIDE, CONTINUOUSLY FROM THE LOWER END OF THE COLUMN, SOLIDIFYING THE MELT, RECRYSTALLIZING THE SOLIDIFIED CRUDE AMMONIUM BIFLUORIDE FROM WATER, AND RECYCLING THE MOTHER LIQUOR FROM THE RECRYSTALLIZATION STEP CONTINUOUSLY INTO THE COLUMN THROUGH THE TOP END THEREOF COUNTERCURRENTLY TO THE EXCESS GASES CONSISTING OF SUBLIMATING AMMONIUM BIFLUORIDE, AMMONIA AND WATER VAPORS RE-
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) | 1964-10-23 | 1965-04-24 | 1965-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-10-23 | 1969-04-24 | 1969-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-10-23 | 1973-04-24 | 1973-10-24 | $7700.00 | Window Closed / Lapsed |