Claims
- 1. A process for the separation of hydrogen fluoride from a liquid mixture comprising hydrogen fluoride and a chlorofluorohydrocarbon liquid selected from the group consisting of 1,1,1-trifluoro-2,2-dichloroethane, 1,1,1,2-tetrafluoro-2-chloroethane, and mixtures thereof, the process comprising:
- (a) adding tetrachloroethylene to the liquid mixture in an amount such that the resulting mixture contains from 20% to 75% by weight of tetrachloroethylene;
- (b) subjecting the mixture from step (a) to a temperature of from -40.degree. to +50.degree. C., and to a pressure at least equal to the total vapor tension of the mixture from step (a) at said temperature, so that two liquid phases are formed, a light phase, and a dense organic phase;
- (c) separating the two liquid phases;
- (d) subjecting the dense organic phase to a partial flash vaporization operation to vaporize 15% to 60% by weight of the dense organic phase, under an absolute pressure of 0.1 to 2 MPa, resulting in two phases, a substantially hydrogen fluoride-free liquid phase comprising tetrachloroethylene and the chlorofluorohydrocarbon liquid and a hydrogen fluoride-enriched gaseous phase;
- (e) separating the resulting substantially hydrogen fluoride-free liquid phase from the hydrogen fluoride-enriched gaseous phase.
- 2. The process of claim 1, wherein the temperature during formation and separation of the two liquid phases is from 0.degree. to 30.degree. C.
- 3. The process of claim 1, wherein the absolute pressure during formation and separation of the two liquid phases is from 0.1 to 1 MPa.
- 4. The process of claim 3, wherein the absolute pressure during the partial flash vaporization operation is from 0.5 to 1.0 MPa.
- 5. The process of claim 1 wherein the partial flash vaporization operation vaporizes from 20% to 50% by weight of the dense organic phase.
Priority Claims (1)
Number |
Date |
Country |
Kind |
MI92A2799 |
Dec 1992 |
ITX |
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Parent Case Info
This is a continuation of U.S. application Ser. No. 08/163,837, filed Dec. 7, 1993 now abandoned.
US Referenced Citations (10)
Foreign Referenced Citations (3)
Number |
Date |
Country |
0003147 |
Jul 1979 |
EPX |
0353970 |
Feb 1990 |
EPX |
718682 |
Nov 1954 |
GBX |
Non-Patent Literature Citations (2)
Entry |
Hawley, Gessner The Condensed Chemical Dictionary, 10 ed. 1981, p. 465 (no month). |
European Search Report dated Mar. 15, 1994 for EP 93 11 8728. |
Continuations (1)
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Number |
Date |
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Parent |
163837 |
Dec 1993 |
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