Claims
- 1. A process for the production of a bis(fluoromethyl)ether composition suitable for use in the production of difluoromethane which comprises contacting formaldehyde with hydrogen fluoride either (i) in the liquid phase or (ii) in the presence of a catalyst in the vapor phase to form a composition comprising bis(fluoromethyl)ether and an equimolar amount of by-product water relative to the bis(fluoromethyl)ether, separating at least part of the by-product water from the composition and recovering a bis(fluoromethyl)ether composition containing less than an equimolar amount of water relative to the bis(fluoromethyl)ether.
- 2. A process for the production of a bis(fluoromethyl)ether composition suitable for use in the production of difluoromethane according to claim 1 which comprises contacting formaldehyde with liquid hydrogen fluoride to form a composition comprising bis(fluoromethyl)ether and an equimolar amount of by-product water relative to the bis(fluoromethyl)ether, separating at least part of the by-product water from the composition and recovering a bis(fluoromethyl)ether composition in which the mole ratio of bis(fluoromethyl)ether to water is at least 2:1.
- 3. A process for the production of a bis(fluoromethyl)ether composition suitable for use in the production of difluoromethane according to claim 1 which comprises contacting formaldehyde with hydrogen fluoride in the vapor phase in the presence of a catalyst form a composition comprising bis(fluoromethyl)ether and an equimolar amount of by-product water relative to the bis(fluoromethyl)ether, separating at least part of the by-product water from the composition and recovering a bis(fluoromethyl)ether composition in which the mole ratio of bis(fluoromethyl)ether to water is at least 2:1.
- 4. A process as claimed in claim 2 wherein the recovered composition comprises at least 20 mole % of bis(fluoromethyl)ether.
- 5. A process as claimed in claim 3 wherein the recovered composition comprises at least 20 mole % of bis(fluoromethyl)ether.
- 6. A process as claimed in claim 1, 2 or 3, wherein water is continually separated from the bis(fluoromethyl)ether.
- 7. A process as claimed in claim 1, 2 or 3, wherein the separation of by-product water is effected by removing bis(fluoromethyl)ether from the as-formed composition.
- 8. A process as claimed in claim 1, 2 or 3, wherein the recovered bis(fluoromethyl)ether composition is suitable for the production of difluoromethane in a yield of greater than 20% based on the bis(fluoromethyl)ether in the composition.
Priority Claims (5)
Number |
Date |
Country |
Kind |
9112817 |
Jun 1991 |
GBX |
|
9112860 |
Jun 1991 |
GBX |
|
9112861 |
Jun 1991 |
GBX |
|
9124087 |
Nov 1991 |
GBX |
|
9126330 |
Dec 1991 |
GBX |
|
Parent Case Info
This is a division of application Ser. No. 8/268,659, filed Jun. 29, 1994, now U.S. Pat. No. 5,463,139, which is a continuation of Ser. No. 08/024,255 filed Mar. 1, 1993, now abandoned; which is a divisional of Ser. No. 07/898,786 filed Jun. 15, 1992, now abandoned.
US Referenced Citations (5)
Number |
Name |
Date |
Kind |
3377394 |
Boudakian et al. |
Apr 1968 |
|
5344998 |
Martin et al. |
Sep 1994 |
|
5386064 |
Woodcock et al. |
Jan 1995 |
|
5446215 |
Cook et al. |
Aug 1995 |
|
5463139 |
Butcher et al. |
Oct 1995 |
|
Foreign Referenced Citations (2)
Number |
Date |
Country |
1025856 |
Mar 1958 |
DEX |
2126216 |
Mar 1984 |
GBX |
Non-Patent Literature Citations (4)
Entry |
Weinmayr, Viktor, Hydrogen Fluoride as a Condensing Agent, VI. Reactions of Fluoroolefins with Formaldehyde in Hydrogen Fluoride, Journal of Org. Chem., vol. 28, Feb. 1963, pp. 492-494. |
Sokol'skii, G.A., Fluoromethyl Esters of Sulfuric Acid, VII. Stability of Difluoromethyl Esters of Fluorosulfonic and Alkylsulfuric Acids, Translated from Zhurnal Obshchei Khimii, vol. 32, No. 4, pp. 1310-1314, Apr. 1962. |
Darragh et al., Journal of Inorganic Nucl. Chemistry, 1970, vol. 32, pp. 1745-1747. |
Hasek et al., J.A.C.S., vol. 82, pp. 543-551 (1913). |
Divisions (2)
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Number |
Date |
Country |
Parent |
268659 |
Jun 1994 |
|
Parent |
898786 |
Jun 1992 |
|
Continuations (1)
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Number |
Date |
Country |
Parent |
24255 |
Mar 1993 |
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