US3196176A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of acetic acid
Assignee: Celanese Corp
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Filing: 1962-03-07
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Granted: 1965-07-20
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Expires: 1982-03-07
Abstract
No abstract record available.
Inventors
- 👤 Wilson W Howell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:23
CPC Classifications
C; C07; C07C; C07C53/00; C07C53/02; C07C51/00; C07C51/42; C07C51/487
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
76 words
A PROCESS FOR PURIFYING ACETIC ACID CONTAINING FORMIC ACID AS THE MAJOR IMPURITY BRINGING SAID ACETIC ACID IN LIQUID FORM INTO INTIMATE CONTACT WITH LIQUID PHOSPHORIC ACID AT A TEMPERATURE ABOVE THE VAPORIZATION TEMPERATURE OF ACETIC ACID, MAINTAINING SAID ACETIC ACID IN SAID INTIMATE CONTACT WITH SAID PHOSPHORIC ACID FOR A TIME SUFFICIENT TO CAUSE VAPORIZATION OF ACETIC ACID AND WITHDRAWING ACETIC ACID VAPORS OF SUBSTANTIALLY LOWER FORMIC ACID CONTENT THAN THE INITIAL ACETIC ACID FEED.
Claim 2
Dependent Claim
76 words
A PROCESS FOR PURIFYING ACETIC ACID CONTAINING FORMIC ACID AS THE MAJOR IMPURITY BRINGING SAID ACETIC ACID IN LIQUID FORM INTO INTIMATE CONTACT WITH LIQUID PHOSPHORIC ACID AT A TEMPERATURE ABOVE THE VAPORIZATION TEMPERATURE OF ACETIC ACID, MAINTAINING SAID ACETIC ACID IN SAID INTIMATE CONTACT WITH SAID PHOSPHORIC ACID FOR A TIME SUFFICIENT TO CAUSE VAPORIZATION OF ACETIC ACID AND WITHDRAWING ACETIC ACID VAPORS OF SUBSTANTIALLY LOWER FORMIC ACID CONTENT THAN THE INITIAL ACETIC ACID FEED.
References Cited (Backward Citations)
US2688635A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-07-19 | 1969-01-18 | 1969-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-07-19 | 1973-01-18 | 1973-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-07-19 | 1977-01-18 | 1977-07-20 | $7700.00 | Window Closed / Lapsed |