US5918481A
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Process for separating hydrogen fluoride from fluorocarbons
Assignee: Honeywell International Inc
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Filing: 1997-11-20
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Granted: 1999-07-06
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Expires: 2017-11-20
Abstract
Abstract The invention provides a method for separating fluorocarbons from mixtures of fluorocarbon and hydrogen fluoride. In particular, the invention provides a method for separating fluorocarbons, such as pentafluoropropane, from azeotropic mixtures of the fluorocarbon and hydrogen fluoride using compositional variations with pressure.
Inventors
- 👤 Hang Thanh Pham
- 👤 Rajiv Ratna Singh
- 👤 Hsueh Sung Tung
- 👤 Daniel Christopher Merkel
- 👤 David Goldschmidt
- 👤 Tadeusz Piotr Rygas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:33
CPC Classifications
C; C01; C01B; C01B7/00; C01B7/19; C01B7/191; C01B7/195; C01B7/196; C07; C07C; C07C17/00; C07C17/38
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
93 words
A process comprising the steps of: (A) distilling a mixture comprising at least an azeotropic mixture of a fluorocarbon and hydrogen fluoride at a first pressure to produce a first overhead stream enriched in either the fluorocarbon or the hydrogen fluoride and a first bottoms stream enriched in the other component; and (B) redistilling the first overhead stream at a second pressure to produce a second overhead stream enriched in the component enriched in the first bottoms stream and a second bottoms stream enriched in the component enriched in the first overhead stream.
Claim 2
Dependent Claim
93 words
A process comprising the steps of: (A) distilling a mixture comprising at least an azeotropic mixture of a fluorocarbon and hydrogen fluoride at a first pressure to produce a first overhead stream enriched in either the fluorocarbon or the hydrogen fluoride and a first bottoms stream enriched in the other component; and (B) redistilling the first overhead stream at a second pressure to produce a second overhead stream enriched in the component enriched in the first bottoms stream and a second bottoms stream enriched in the component enriched in the first overhead stream.
Claim 3
Dependent Claim
24 words
The process of claim 1 wherein the fluorocarbon is a C 3 to C 5 alkane or alkene containing at least one fluorine atom.
Claim 4
Dependent Claim
24 words
The process of claim 1 wherein the fluorocarbon is selected from the group consisting of isomers of pentafluoropropane, hexafluoropropane, heptafluoropropane, hexafluorobutane, octafluorobutane, and pentafluorobutene.
Claim 5
Dependent Claim
20 words
The process of claim 3 wherein the fluorocarbon is selected from the group consisting of 1,1,1,3,3-pentafluoropropane, 1,1,1,2,2,4-hexafluorobutane, 1,1,1,3,3,4,4,4-octafluorobutane, and 1,1,1,2,2-pentafluorobutene.
Claim 6
Dependent Claim
10 words
The process of claim 4 wherein the fluorocarbon is 1,1,1,3,3-pentafluoropropane.
Claim 7
Dependent Claim
10 words
The process of claim 4 wherein the fluorocarbon is 1,1,1,2,2,4-hexafluorobutane.
Claim 8
Dependent Claim
10 words
The process of claim 4 wherein the fluorocarbon is 1,1,1,3,3,4,4,4-octafluorobutane.
Claim 9
Dependent Claim
10 words
The process of claim 4 wherein the fluorocarbon is 1,1,1,2,2-pentafluorobutene.
Claim 10
Dependent Claim
32 words
The process of claim 1 wherein the first distillation pressure is from about 50 to about 400 psia and the second distillation pressure is from about 5 psia to about 50 psia.
Claim 11
Dependent Claim
32 words
The process of claim 1 wherein the first distillation pressure is from about 5 psia to about 50 psia and the second distillation pressure is from about 50 to about 400 psia.
Claim 12
Dependent Claim
133 words
A process comprising the steps of: (A) distilling a mixture comprising at least an azeotropic mixture of a C 3 to C 5 alkane or alkene containing at least one fluorine atom and hydrogen fluoride at a first pressure to produce a first overhead stream enriched in either the fluorocarbon or the hydrogen fluoride and a first bottoms stream enriched in the other component; and (B) redistilling the first overhead stream at a second pressure to produce a second overhead stream enriched in the component enriched in the first bottoms stream and a second bottoms stream enriched in the component enriched in the first overhead stream wherein the first distillation pressure is from about 50 to about 400 psia and the second distillation pressure is from about 5 psia to about 50 psia.
Claim 13
Dependent Claim
133 words
A process comprising the steps of: (A) distilling a mixture comprising at least an azeotropic mixture of a C 3 to C 5 alkane or alkene containing at least one fluorine atom and hydrogen fluoride at a first pressure to produce a first overhead stream enriched in either the fluorocarbon or the hydrogen fluoride and a first bottoms stream enriched in the other component; and (B) redistilling the first overhead stream at a second pressure to produce a second overhead stream enriched in the component enriched in the first bottoms stream and a second bottoms stream enriched in the component enriched in the first overhead stream wherein the first distillation pressure is from about 50 to about 400 psia and the second distillation pressure is from about 5 psia to about 50 psia.
Claim 14
Dependent Claim
27 words
The process of claim 11 wherein the C 3 to C 5 alkane or alkene is selected from the group consisting of 1,1,1,3,3-pentafluoropropane, 1,1,1,2,2,4-hexafluorobutane, 1,1,1,3,3,4,4,4-octafluorobutane, and 1,1,1,2,2-pentafluorobutene.
Claim 15
Dependent Claim
10 words
The process of claim 12 wherein the fluorocarbon is 1,1,1,3,3-pentafluoropropane.
Claim 16
Dependent Claim
10 words
The process of claim 12 wherein the fluorocarbon is 1,1,1,2,2,4-hexafluorobutane.
Claim 17
Dependent Claim
10 words
The process of claim 12 wherein the fluorocarbon is 1,1,1,3,3,4,4,4-octafluorobutane.
Claim 18
Dependent Claim
10 words
The process of claim 12 wherein the fluorocarbon is 1,1,1,2,2-pentafluorobutene.
Claim 19
Dependent Claim
132 words
A process comprising the steps of: (A) distilling a mixture comprising at least an azeotropic mixture of a C 3 to C 5 alkane or alkene containing at least one fluorine atom and hydrogen fluoride at a first pressure to produce a first overhead stream enriched in either the fluorocarbon or the hydrogen fluoride and a first bottoms stream enriched in the other component; and (B) redistilling the first overhead stream at a second pressure to produce a second overhead stream enriched in the component enriched in the first bottoms stream and a second bottoms stream enriched in the component enriched in the first overhead stream wherein the first distillation pressure is from about 5 psia to about 50 psia and the second distillation pressure is from about 50 to about 400.
Claim 20
Dependent Claim
132 words
A process comprising the steps of: (A) distilling a mixture comprising at least an azeotropic mixture of a C 3 to C 5 alkane or alkene containing at least one fluorine atom and hydrogen fluoride at a first pressure to produce a first overhead stream enriched in either the fluorocarbon or the hydrogen fluoride and a first bottoms stream enriched in the other component; and (B) redistilling the first overhead stream at a second pressure to produce a second overhead stream enriched in the component enriched in the first bottoms stream and a second bottoms stream enriched in the component enriched in the first overhead stream wherein the first distillation pressure is from about 5 psia to about 50 psia and the second distillation pressure is from about 50 to about 400.
Claim 21
Dependent Claim
27 words
The process of claim 17 wherein the C 3 to C 5 alkane or alkene is selected from the group consisting of 1,1,1,3,3-pentafluoropropane, 1,1,1,2,2,4-hexafluorobutane, 1,1,1,3,3,4,4,4-octafluorobutane, and 1,1,1,2,2-pentafluorobutene.
Claim 22
Dependent Claim
10 words
The process of claim 18 wherein the fluorocarbon is 1,1,1,3,3-pentafluoropropane.
Claim 23
Dependent Claim
10 words
The process of claim 18 wherein the fluorocarbon is 1,1,1,2,2,4-hexafluorobutane.
Claim 24
Dependent Claim
10 words
The process of claim 18 wherein the fluorocarbon is 1,1,1,3,3,4,4,4-octafluorobutane.
Claim 25
Dependent Claim
10 words
The process of claim 18 wherein the fluorocarbon is 1,1,1,2,2-pentafluorobutene.
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