US4005137A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the purification and separation of perhaloalkanoic acids from mixtures thereof with perhaloalkanes
Assignee: Kali Chemie AG
•
Filing: 1975-02-10
•
Granted: 1977-01-25
•
Expires: 1995-02-10
Abstract
Abstract Processes for the separation and purification of a perhaloalkanoic acid or mixture of perhaloalkanoic acids having the formula A--(CFX--CFY).sub.n --CFX--COOH in which A is a perfluoromethyl, perfluoroethyl, perfluoropropyl or perfluoroisopropyl radical, X is a fluoro or a trifluoromethyl radical, Y is a fluoro or chloro radical, and n is an integer from 1 to 4, from a mixture containing the said acid or mixture of acids and a perhaloalkane or mixture of perhaloalkanes having the formula A--(CFX--CFY).sub.n --CFX--CFYZ in which formula A, X, Y and n have the same significance as in the previous formula and Z is an iodo, chloro or bromo radical, which comprises adsorbing the said mixture in the form of a liquid upon a chromatographic column of adsorbent silica gel particles and subsequently eluting the perhaloalkane or perhaloalkanes therefrom with a weakly polar eluent and subsequently eluting the perfluoroalkanoic acid or acids therefrom with a strongly polar eluent.
Inventors
- 👤 Werner Rudolph
- 👤 Joachim Massonne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 15:28
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/42; C07C51/47
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
170 words
A process for the separation and purification of a perhaloalkanoic acid or mixture of perhaloalkanoic acids having the formula A--(CFX--CFY).sub.n --CFX--COOH in which A is a perfluoromethyl, perfluoroethyl, perfluoropropyl or perfluoroisopropyl radical, X is a fluoro or a trifluoromethyl radical, Y is a fluoro or chloro radical and n is an integer from 1 to 4, from a mixture containing the said acid or mixture of acids and a perhaloalkane or mixture of perhaloalkanes having the formula A--(CFX--CFY).sub.n --CFX--CFYZ in which formula A, X, Y and n have the same significance as hereinbefore, and Z is an iodo, chloro or bromo radical, which comprises adsorbing the said mixture in the form of a liquid upon a chromatographic column of adsorbent silica gel particles and subsequently eluting the perhaloalkane or perhaloalkanes therefrom first with a weakly polar eluent selected from the group consisting of chlorofluoroalkanes, tetrachloromethane, chloroform, benzene and petroleum ether, and then with a strongly polar eluent selected from the group consisting of ethyl acetate, diethyl ether, acetone and methanol.
Claim 2
Dependent Claim
170 words
A process for the separation and purification of a perhaloalkanoic acid or mixture of perhaloalkanoic acids having the formula A--(CFX--CFY).sub.n --CFX--COOH in which A is a perfluoromethyl, perfluoroethyl, perfluoropropyl or perfluoroisopropyl radical, X is a fluoro or a trifluoromethyl radical, Y is a fluoro or chloro radical and n is an integer from 1 to 4, from a mixture containing the said acid or mixture of acids and a perhaloalkane or mixture of perhaloalkanes having the formula A--(CFX--CFY).sub.n --CFX--CFYZ in which formula A, X, Y and n have the same significance as hereinbefore, and Z is an iodo, chloro or bromo radical, which comprises adsorbing the said mixture in the form of a liquid upon a chromatographic column of adsorbent silica gel particles and subsequently eluting the perhaloalkane or perhaloalkanes therefrom first with a weakly polar eluent selected from the group consisting of chlorofluoroalkanes, tetrachloromethane, chloroform, benzene and petroleum ether, and then with a strongly polar eluent selected from the group consisting of ethyl acetate, diethyl ether, acetone and methanol.
Claim 3
Dependent Claim
36 words
A process as described in claim 1 in which the ratio by weight of the silica gel adsorbent particles to the mixture containing the perhaloalkanoic acids before the adsorbent is eluted is between 2:1 and 5:1.
Claim 4
Dependent Claim
36 words
A process as defined in claim 1 in which the ratio by weight of the silica gel adsorbent particles to the mixture containing the perhaloalkanoic acids before the adsorbent is eluted is between 3:1 and 4:1.
Claim 5
Dependent Claim
31 words
A process as defined in claim 1 in which the silica gel adsorbent particles are reactivated by rinsing with 1,1,2-trichloro-1,2,2-trifluoroethane and subsequent heating at a temperature between 140° and 150° C.
Claim 6
Dependent Claim
16 words
A process as defined in claim 1 in which the eluent for the perhaloalkanes is 1,1,2-trichloro-1,2,2-trifluoroethane.
Claim 7
Dependent Claim
18 words
A process as defined in claim 1 in which the eluent for the perfluoroalkanoic acids is diethyl ether.
References Cited (Backward Citations)
US3040081A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-01-25 | 1980-07-26 | 1981-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-01-25 | 1984-07-26 | 1985-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-01-25 | 1988-07-26 | 1989-01-25 | $7700.00 | Window Closed / Lapsed |