US4209470A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the separation of hydrogen fluoride from its mixtures with 1-chloro-1,1-difluoroethane
Assignee: Solvay SA
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Filing: 1979-01-10
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Granted: 1980-06-24
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Expires: 1999-01-10
Abstract
Abstract Process for the separation of hydrogen fluoride from its mixtures with 1-chloro-1,1-difluoroethane, such as those obtained in the manufacture of the latter. An auxiliary solvent, chosen from among 1,1-dichloro-1-fluoroethane, vinylidene chloride, 1,1,1-trichloroethane and mixtures thereof, is added to the mixture so as to obtain two separate liquid phases, one of which contains the hydrogen fluoride and the other of which contains the 1-chloro-1,1-difluoroethane. Virtually all the hydrogen fluoride is recovered in the anhydrous form in the manufacture of monomers such as vinylidene fluoride, from chlorohydrocarbons such as vinylidene chloride and 1,1,1-trichloroethane.
Inventors
- 👤 Robert Lorquet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:15
CPC Classifications
C; C07; C07C; C07C17/00; C07C17/38; C01; C01B; C01B7/00; C01B7/19; C01B7/191; C01B7/195
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
67 words
Process for the separation of hydrogen fluoride from its liquid mixtures with 1-chloro-1,1-difluoroethane, comprising: separating the liquid mixture by decantation to obtain a liquid organic phase enriched in 1-chloro-1,1-difluoroethane and a liquid organic phase enriched in hydrogen fluoride by adding to the mixture a liquid containing an auxiliary solvent, selected from the group consisting of 1,1-dichloro-1-fluoroethane, vinylidene chloride, 1,1,1-trichloroethane and mixtures thereof, before subjecting it to decantation.
Claim 2
Dependent Claim
67 words
Process for the separation of hydrogen fluoride from its liquid mixtures with 1-chloro-1,1-difluoroethane, comprising: separating the liquid mixture by decantation to obtain a liquid organic phase enriched in 1-chloro-1,1-difluoroethane and a liquid organic phase enriched in hydrogen fluoride by adding to the mixture a liquid containing an auxiliary solvent, selected from the group consisting of 1,1-dichloro-1-fluoroethane, vinylidene chloride, 1,1,1-trichloroethane and mixtures thereof, before subjecting it to decantation.
Claim 3
Dependent Claim
21 words
Process according to claim 1, wherein the liquid added contains less than 50% by weight of 1-chloro-1,1-difluoroethane and of hydrogen fluoride.
Claim 4
Dependent Claim
18 words
Process according to claim 2, wherein the liquid added is formed exclusively of 1,1-dichloro-1-fluoroethane, vinylidene chloride and 1,1,1-trichloroethane.
Claim 5
Dependent Claim
30 words
Process according to claim 1, wherein the liquid added is employed at the rate of about 0.05 to 2.5 mols of 1,1-dichloro-1-fluoroethane, vinylidene chloride and 1,1,1-trichloroethane per mol of 1-chloro-1,1-difluoroethane.
Claim 6
Dependent Claim
17 words
Process according to claim 1, wherein the separation is carried out at a temperature below 110° C.
Claim 7
Dependent Claim
22 words
Process according to claim 1, wherein the separation is carried out at a pressure ranging from 0.8 to 30 kg/cm 2 .
Claim 8
Dependent Claim
20 words
Process according to claim 1, wherein the liquid added is a reaction mixture originating from the hydrofluorination of vinylidene chloride.
Claim 9
Dependent Claim
19 words
Process according to claim 1, wherein the liquid added is a reaction mixture originating from the hydrofluorination of 1,1,1-trichloroethane.
Claim 10
Dependent Claim
29 words
Process according to claim 1, wherein the mixture of hydrogen fluoride and 1-chloro-1,1-difluoroethane subjected to the separation contains at least 80% by weight of hydrogen fluoride and of 1-chloro-1,1-difluoroethane.
Claim 11
Dependent Claim
25 words
Process according to claim 1, wherein the mixture of hydrogen fluoride and 1-chloro-1,1-difluoroethane subjected to the separation has a composition similar to the azeotropic composition.
Claim 12
Dependent Claim
63 words
Process according to claim 1, wherein the separation is carried out in a condenser/decanter in which the top product from two distillations is condensed, to which product the liquid is added and from which the liquid organic phase is withdrawn and fed into the reflux of one distillation and the liquid inorganic phase is withdrawn and fed into the reflux of the other.
Claim 13
Dependent Claim
25 words
Process according to claim 11, wherein the top product has a composition similar to the azeotropic composition of the mixtures of hydrogen fluoride and 1-chloro-1,1-difluoroethane.
References Cited (Backward Citations)
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US3696156A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-06-24 | 1983-12-24 | 1984-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-06-24 | 1987-12-24 | 1988-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-06-24 | 1991-12-24 | 1992-06-24 | $7700.00 | Window Closed / Lapsed |