Patent US5072277A successfully refreshed from Google Patents.
Patent US2987451A successfully refreshed from Google Patents.
US2987451A
Expired / Lapsed
US
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Process for purifying acrylonitrile
Assignee: Knapsack AG
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Filing: 1958-02-12
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Granted: 1961-06-06
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Expires: 1978-02-12
Abstract
No abstract record available.
Inventors
- 👤 Sennewald Kurt
- 👤 Born Klaus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:12
CPC Classifications
C; C07; C07C; C07C253/00; C07C253/32; C07C253/34; Y; Y10; Y10S; Y10S203/00; Y10S203/03
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
51 words
A PROCESS FOR PURIFICATION OF METHYLVINYL KETONE CONTAMINATED ACRYLONITRILE CONTAINING UP TO ABOUT 0.75% BY WEIGHT OF METHYLVINYL KETONE WHICH COMPRISES TREATING THE CRUDE ACRYLONITRILE WITH AT LEAST ONE ALIPHATIC ALCOHOL IN A NONNEUTRAL MEDIUM AT A TEMPERATURE BELOW THE BOILING POINT OF ACRYLONITRILE, AND SUBSEQUENTLY DISTILLING OFF THE PURE ACRYLONITRILE.
Claim 2
Dependent Claim
51 words
A PROCESS FOR PURIFICATION OF METHYLVINYL KETONE CONTAMINATED ACRYLONITRILE CONTAINING UP TO ABOUT 0.75% BY WEIGHT OF METHYLVINYL KETONE WHICH COMPRISES TREATING THE CRUDE ACRYLONITRILE WITH AT LEAST ONE ALIPHATIC ALCOHOL IN A NONNEUTRAL MEDIUM AT A TEMPERATURE BELOW THE BOILING POINT OF ACRYLONITRILE, AND SUBSEQUENTLY DISTILLING OFF THE PURE ACRYLONITRILE.
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) | 1964-06-05 | 1964-12-05 | 1965-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-06-05 | 1968-12-05 | 1969-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-06-05 | 1972-12-05 | 1973-06-06 | $7700.00 | Window Closed / Lapsed |