US5196616A
Expired / Lapsed
US
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Process for separating and recovering fluorocarbons and hydrogen fluoride from mixtures thereof
Assignee: EIDP Inc
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Filing: 1991-10-18
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Granted: 1993-03-23
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Expires: 2011-10-18
Abstract
Abstract A process for separating and recovering an organic phase (e.g., fluorocarbons such as chlorofluorocarbons, hydrochlorofluorocarbons, hydrofluorocarbons and perfluorocarbons) from a feed stream of a mixture of fluorocarbons and hydrogen fluoride, wherein the mixture is characterized as forming at least one azeotrope or azeotrope-like composition involving at least one fluorocarbon and hydrogen fluoride, by passing the fluorocarbon/HF mixture feed stream through the feed side of a semipermeable membrane unit and then further separating a fluorocarbon-depleted hydrogen fluoride permeate stream and a fluorocarbon enriched residual stream exiting the membrane unit by conventional distillation. An essentially pure fluorocarbon phase and hydrogen fluoride phase are recovered from the distillation with the azeotrope or azeotrope-like distillate being recycled to the inlet of the semipermeable membrane unit.
Inventors
- 👤 Kung H. Lee
- 👤 Domenic J. Barsotti
- 👤 Edward K. Sakata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:38
CPC Classifications
C; C01; C01B; C01B7/00; C01B7/19; C01B7/191; C01B7/195; C07; C07C; C07C17/00; C07C17/38; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/582
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
181 words
A process for separating and recovering a fluorocarbon phase and a hydrogen fluoride phase from a feed stream of a mixture of fluorocarbon and hydrogen fluoride wherein said mixture is characterized as forming at least one azeotrope or azeotrope-like composition involving at least one fluorocarbon and hydrogen fluoride, comprising the steps of: (a) providing a semipermeable membrane means for separating fluorocarbon from hydrogen fluoride having a feed side and a permeate side wherein said semipermeable membrane means is characterized as having a selectivity for allowing the passage of hydrogen fluoride relative to the fluorocarbon phase of at least 3; (b) passing a feed stream of fluorocarbon and hydrogen fluoride across the feed side of the semipermeable membrane such that hydrogen fluoride passes preferentially through the membrane thus forming a fluorocarbon-depleted hydrogen fluoride permeate stream and a fluorocarbon enriched residual stream; (c) subjecting said fluorocarbon-depleted hydrogen fluoride permeate stream produced in step (b) to distillation, thus separating and recovering hydrogen fluoride; and (d) subjecting said fluorocarbon enriched residual stream produced in step (b) to distillation, thus separating and recovering a fluorocarbon phase.
Claim 2
Dependent Claim
181 words
A process for separating and recovering a fluorocarbon phase and a hydrogen fluoride phase from a feed stream of a mixture of fluorocarbon and hydrogen fluoride wherein said mixture is characterized as forming at least one azeotrope or azeotrope-like composition involving at least one fluorocarbon and hydrogen fluoride, comprising the steps of: (a) providing a semipermeable membrane means for separating fluorocarbon from hydrogen fluoride having a feed side and a permeate side wherein said semipermeable membrane means is characterized as having a selectivity for allowing the passage of hydrogen fluoride relative to the fluorocarbon phase of at least 3; (b) passing a feed stream of fluorocarbon and hydrogen fluoride across the feed side of the semipermeable membrane such that hydrogen fluoride passes preferentially through the membrane thus forming a fluorocarbon-depleted hydrogen fluoride permeate stream and a fluorocarbon enriched residual stream; (c) subjecting said fluorocarbon-depleted hydrogen fluoride permeate stream produced in step (b) to distillation, thus separating and recovering hydrogen fluoride; and (d) subjecting said fluorocarbon enriched residual stream produced in step (b) to distillation, thus separating and recovering a fluorocarbon phase.
Claim 3
Dependent Claim
170 words
A process of claim 1 wherein said fluorocarbon-depleted hydrogen fluoride permeate stream is further characterized as having a hydrogen fluoride concentration above that characteristic of the azeotrope or azeotrope-like composition involving at least one fluorocarbon and hydrogen fluoride such that at least a portion of any remaining azeotrope or azeotrope-like composition involving at least one fluorocarbon and hydrogen fluoride is also separated and recovered in step (c) and wherein said fluorocarbon-enriched residual streams is further characterized as having a hydrogen fluoride concentration below that characteristic of the azeotrope or azeotrope-like composition involving at least one fluorocarbon and hydrogen fluoride such that at least a portion of any remaining azeotrope or azeotrope-like composition involving at least one fluorocarbon and hydrogen fluoride is also separated and recovered in step (d) and wherein at least a portion of any of said remaining azeotrope or azeotrope-like composition involving at least one fluorocarbon and hydrogen fluoride separated and recovered in steps (c) and (d) is recycled to the inlet side of said semipermeable membrane unit.
Claim 4
Dependent Claim
25 words
A process of claim 1 wherein the fluorocarbon is selected from the group consisting of C 1 to C 3 chlorofluorocarbons, hydrochlorofluorocarbons, hydrofluorocarbons and perfluorocarbons.
Claim 5
Dependent Claim
25 words
A process of claim 2 wherein the fluorocarbon is selected from the group consisting of C 1 to C 3 chlorofluorocarbons, hydrochlorofluorocarbons, hydrofluorocarbons and perfluorocarbons.
Claim 6
Dependent Claim
10 words
A process of claim 1 wherein the fluorocarbon is difluoromethane.
Claim 7
Dependent Claim
10 words
A process of claim 2 wherein the fluorocarbon is difluoromethane.
Claim 8
Dependent Claim
10 words
A process of claim 1 wherein the fluorocarbon is chlorodifluoromethane.
Claim 9
Dependent Claim
10 words
A process of claim 2 wherein the fluorocarbon is chlorodifluoromethane.
Claim 10
Dependent Claim
15 words
A process of claim 1 wherein the fluorocarbon is a mixture of 2-chloro-1,1,1,2-tetrafluoroethane and 1,1,1,2-tetrafluoroethane.
Claim 11
Dependent Claim
15 words
A process of claim 2 wherein the fluorocarbon is a mixture of 2-chloro-1,1,1,2-tetrafluoroethane and 1,1,1,2-tetrafluoroethane.
Claim 12
Dependent Claim
15 words
A process of claim 1 wherein the fluorocarbon is a mixture of 2-chloro-1,1,1,2-tetrafluoroethane and pentafluoroethane.
Claim 13
Dependent Claim
15 words
A process of claim 2 wherein the fluorocarbon is a mixture of 2-chloro-1,1,1,2-tetrafluoroethane and pentafluoroethane.
Claim 14
Dependent Claim
162 words
A process for separating and recovering a fluorocarbon phase and a hydrogen fluoride phase from a feed stream of a mixture of fluorocarbon and hydrogen fluoride wherein said mixture is characterized as forming at least one azeotrope or azeotrope-like composition involving at least one fluorocarbon and hydrogen fluoride, comprising the steps of: (a) providing a semipermeable membrane means for separating fluorocarbon from hydrogen fluoride having a feed side and a permeate side wherein said semipermeable membrane means is characterized as having a selectivity for allowing the passage of hydrogen fluoride relative to the fluorocarbon organic phase of at least 3; (b) passing a feed stream of fluorocarbon and hydrogen fluoride across the feed side of the semipermeable membrane such that hydrogen fluoride passes preferentially through the membrane thus forming a fluorocarbon-depleted hydrogen fluoride permeate stream and a fluorocarbon enriched residual stream; and (c) subjecting said fluorocarbon-depleted hydrogen fluoride permeate stream produced in step (b) to distillation, thus separating and recovering hydrogen fluoride.
Claim 15
Dependent Claim
162 words
A process for separating and recovering a fluorocarbon phase and a hydrogen fluoride phase from a feed stream of a mixture of fluorocarbon and hydrogen fluoride wherein said mixture is characterized as forming at least one azeotrope or azeotrope-like composition involving at least one fluorocarbon and hydrogen fluoride, comprising the steps of: (a) providing a semipermeable membrane means for separating fluorocarbon from hydrogen fluoride having a feed side and a permeate side wherein said semipermeable membrane means is characterized as having a selectivity for allowing the passage of hydrogen fluoride relative to the fluorocarbon organic phase of at least 3; (b) passing a feed stream of fluorocarbon and hydrogen fluoride across the feed side of the semipermeable membrane such that hydrogen fluoride passes preferentially through the membrane thus forming a fluorocarbon-depleted hydrogen fluoride permeate stream and a fluorocarbon enriched residual stream; and (c) subjecting said fluorocarbon-depleted hydrogen fluoride permeate stream produced in step (b) to distillation, thus separating and recovering hydrogen fluoride.
Claim 16
Dependent Claim
162 words
A process for separating and recovering a fluorocarbon phase and a hydrogen fluoride phase from a feed stream of a mixture of fluorocarbon and hydrogen fluoride wherein said mixture is characterized as forming at least one azeotrope or azeotrope-like composition involving at least one fluorocarbon and hydrogen fluoride, comprising the steps of: (a) providing a semipermeable membrane means for separating fluorocarbon from hydrogen fluoride having a feed side and a permeate side wherein said semipermeable membrane means is characterized as having a selectivity for allowing the passage of hydrogen fluoride relative to the fluorocarbon organic phase of at least 3; (b) passing a feed stream of fluorocarbon and hydrogen fluoride across the feed side of the semipermeable membrane such that hydrogen fluoride passes preferentially through the membrane thus forming a fluorocarbon-depleted hydrogen fluoride permeate stream and a fluorocarbon enriched residual stream; and (c) subjecting said fluorocarbon enriched residual stream produced in step (b) to distillation, thus separating and recovering a fluorocarbon phase.
Claim 17
Dependent Claim
162 words
A process for separating and recovering a fluorocarbon phase and a hydrogen fluoride phase from a feed stream of a mixture of fluorocarbon and hydrogen fluoride wherein said mixture is characterized as forming at least one azeotrope or azeotrope-like composition involving at least one fluorocarbon and hydrogen fluoride, comprising the steps of: (a) providing a semipermeable membrane means for separating fluorocarbon from hydrogen fluoride having a feed side and a permeate side wherein said semipermeable membrane means is characterized as having a selectivity for allowing the passage of hydrogen fluoride relative to the fluorocarbon organic phase of at least 3; (b) passing a feed stream of fluorocarbon and hydrogen fluoride across the feed side of the semipermeable membrane such that hydrogen fluoride passes preferentially through the membrane thus forming a fluorocarbon-depleted hydrogen fluoride permeate stream and a fluorocarbon enriched residual stream; and (c) subjecting said fluorocarbon enriched residual stream produced in step (b) to distillation, thus separating and recovering a fluorocarbon phase.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1996-03-22 | 1996-09-21 | 1997-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-03-22 | 2000-09-21 | 2001-03-23 | $3760.00 | Window Closed / Lapsed |
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