Patent US3702887A successfully refreshed from Google Patents.
US3702887A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the manufacture of hydrogen cyanide from formamide
Assignee: Knapsack AG
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Filing: 1970-12-04
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Granted: 1972-11-14
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Expires: 1990-12-04
Abstract
Abstract COLLECTED IN ONE OR MORE CONDENSERS; A PORTION OF HYDROCYANIC ACID IS CONTINUOUSLY REMOVED THEREFROM, RECYCLED TO THE HEAD OF THE CONDENSER(S) AND SPRAYED THEREINTO. IMPROVED PRODUCTION OF AQUEOUS HYDROCYANIC ACID BY SUBJECTING FORMAMIDE TO A CLEAVAGE REACTION UNDER REDUCED PRESSURE AND AT ELEVATED TEMPERATURES, WHEREIN THE HYDROCYANIC ACID-CONTAINING CLEAVAGE GAS, WHICH IS FREED FROM AMMONIA AND COOLED, IS COMPRESSED SUBSTANTIALLY TO ATMOSPHERIC PRESSURE AND LIQUEFIED. THE COMPRESSED CLEAVAGE GAS IS MORE PARTICULARLY LIQUEFIED IN ONE OR MORE CONDENSERS, WHICH ARE ARRANGED IN UPRIGHT POSITION AND SERIES-CONNECTED TOGETHER; THE RESULTING AQUEOUS HYDROCYANIC ACID IS
Inventors
- 👤 Kurt Sennewald
- 👤 Rudolf Wesselmann
- 👤 Ernst Holler
- 👤 Heinz Muller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:37
CPC Classifications
C; C01; C01C; C01C3/00; C01C3/02; C01C3/0204
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) | 1975-11-14 | 1976-05-15 | 1976-11-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-11-14 | 1980-05-15 | 1980-11-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-11-14 | 1984-05-15 | 1984-11-14 | $7700.00 | Window Closed / Lapsed |