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US5051114A Expired / Lapsed US ⏱️ 0.0 years remaining

Perfluorodioxole membranes

Assignee: DuPont Canada Inc
•
Filing: 1990-06-13
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Granted: 1991-09-24
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Expires: 2010-06-13
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Abstract

Abstract A selectively permeable membrane for the separation or enrichment of gaseous mixtures may be formed from amorphous polymers of perfluoro-2,2-dimethyl-1,3-dioxole, especially copolymers with a complementary amount of at least one of tetrafluoroethylene, perfluoromethyl vinyl ether, vinylidene fluoride and chlorotrifluoroethylene. Preferably, the polymer is a dipolymer containing 65-99 mole % of perfluoro-2,2-dimethyl-1,3-dioxole and having a glass transition temperature of at least 140 DEG C. The membranes may be used for the separation or enrichment of a wide variety of gaseous mixtures, including oxygen enrichment of air, and separation or enrichment of gaseous organic compounds in admixture with air, including separation or enrichment of the amount of fluorocarbon gases in air. The membranes exhibit a very high flux rate, compared with other glassy organic polymer membranes.

Inventors

  • 👤 Stuart M. Nemser
  • 👤 Ian C. Roman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 21:59
CPC Classifications
B; B01; B01D; B01D71/00; B01D71/06; B01D71/30; B01D71/32; B01D53/00; B01D53/22; B01D53/228; B01D71/44; B01D71/76

Claims Analysis

Total Claims: 44
Claim 1
Independent Claim 125 words
A method for the enrichment of the amount of a gaseous organic compound in a gaseous admixture of said organic compound and at least one of oxygen and nitrogen, said method comprising: (a) providing in a membrane separation cell a selectively permeable membrane having a feed side and a permeate side, said membrane being virtually defect-free with an oxygen/nitrogen selectivity of at least 1.4 and formed from an amorphous polymer of perfluoro-2,2-dimethyl-1,3-dioxole, and feeding said admixture to the feed side of said membrane, said membrane being at a temperature of less than the glass transition temperature of the polymer; and (b) removing from the feed side of the membrane, a gaseous admixture of said organic compound that is enriched in the amount of organic compound.
Claim 2
Independent Claim 125 words
A method for the enrichment of the amount of a gaseous organic compound in a gaseous admixture of said organic compound and at least one of oxygen and nitrogen, said method comprising: (a) providing in a membrane separation cell a selectively permeable membrane having a feed side and a permeate side, said membrane being virtually defect-free with an oxygen/nitrogen selectivity of at least 1.4 and formed from an amorphous polymer of perfluoro-2,2-dimethyl-1,3-dioxole, and feeding said admixture to the feed side of said membrane, said membrane being at a temperature of less than the glass transition temperature of the polymer; and (b) removing from the feed side of the membrane, a gaseous admixture of said organic compound that is enriched in the amount of organic compound.
Claim 3
Dependent Claim 15 words
The method of claim 1 in which a pressure differential is applied across the membrane.
Claim 4
Dependent Claim 26 words
The method of claim 1 in which the temperature of the membrane is at least 30° C. lower than the glass transition temperature of the polymer.
Claim 5
Dependent Claim 23 words
The method of claim 1 in which the membrane has a selective permeation of nitrogen over the organic compound of at least 10:1.
Claim 6
Dependent Claim 14 words
The method of claim 1 in which the organic compound is a gaseous fluorocarbon.
Claim 7
Dependent Claim 14 words
The method of claim 1 in which the organic compound is a gaseous hydrocarbon.
Claim 8
Dependent Claim 14 words
The method of claim 1 in which the polymer is a copolymer of perfluoro-2,2-dimethyl-1,3-dioxole.
Claim 9
Dependent Claim 37 words
The method of claim 7 in which the polymer is a copolymer of perfluoro-2,2-dimethyl-1,3-dioxole and a complementary amount of at least one monomer selected from the group consisting of tetrafluoroethylene, perfluoromethyl vinyl ether, vinylidene fluoride and chlorotrifluoroethylene.
Claim 10
Dependent Claim 14 words
The method of claim 1 in which the polymer is a homopolymer of perfluoro-2,2-dimethyl-1,3-dioxole.
Claim 11
Dependent Claim 20 words
The method of claim 1 in which the polymer is a dipolymer of perfluoro-2,2-dimethyl-1,3-dioxole and a complementary amount of tetrafluoroethylene.
Claim 12
Dependent Claim 29 words
The method of claim 10 in which the polymer is a dipolymer containing 65-99 mole % of perfluoro-2,2-dimethyl-1,3-dioxole and having a glass transition temperature of at least 140° C.
Claim 13
Dependent Claim 19 words
The method of claim 11 in which the membrane has a permeability to oxygen of at least 100 Barrers.
Claim 14
Dependent Claim 16 words
The method of claim 12 in which the permeability to oxygen is at least 200 Barrers.
Claim 15
Dependent Claim 16 words
The method of claim 12 in which the permeability to oxygen is at least 500 Barrers.
Claim 16
Independent Claim 110 words
A method for the enrichment of the amount of a gas in a gaseous admixture with another gas, said method comprising: (a) providing in a membrane separation cell a selectively permeable membrane having a feed side and a permeate side, said membrane being virtually defect-free with an oxygen/nitrogen selectivity of at least 1.4 and formed from an amorphous polymer of perfluoro-2,2-dimethyl-1,3-dioxole, and feeding said admixture to the feed side of said membrane, said membrane being at a temperature of less than the glass transition temperature of the polymer; and (b) removing from the permeate side of the membrane, a gaseous admixture that is enriched in the amount of one gas.
Claim 17
Independent Claim 110 words
A method for the enrichment of the amount of a gas in a gaseous admixture with another gas, said method comprising: (a) providing in a membrane separation cell a selectively permeable membrane having a feed side and a permeate side, said membrane being virtually defect-free with an oxygen/nitrogen selectivity of at least 1.4 and formed from an amorphous polymer of perfluoro-2,2-dimethyl-1,3-dioxole, and feeding said admixture to the feed side of said membrane, said membrane being at a temperature of less than the glass transition temperature of the polymer; and (b) removing from the permeate side of the membrane, a gaseous admixture that is enriched in the amount of one gas.
Claim 18
Dependent Claim 15 words
The method of claim 15 in which a pressure differential is applied across the membrane.
Claim 19
Dependent Claim 26 words
The method of claim 15 in which the temperature of the membrane is at least 30° C. lower than the glass transition temperature of the dipolymer.
Claim 20
Dependent Claim 14 words
The method of claim 15 in which the polymer is a copolymer of perfluoro-2,2-dimethyl-1,3-dioxole.
Claim 21
Dependent Claim 37 words
The method of claim 18 in which the polymer is a copolymer of perfluoro-2,2-dimethyl-1,3-dioxole and a complementary amount of at least one monomer selected from the group consisting of tetrafluoroethylene, perfluoromethyl vinyl ether, vinylidene fluoride and chlorotrifluoroethylene.
Claim 22
Dependent Claim 20 words
The method of claim 19 in which the polymer is a dipolymer of perfluoro-2,2-dimethyl-1,3-dioxole and a complementary amount of tetrafluoroethylene.
Claim 23
Dependent Claim 29 words
The method of claim 20 in which the polymer is a dipolymer containing 65-99 mole % of perfluoro-2,2-dimethyl-1,3-dioxole and having a glass transition temperature of at least 140° C.
Claim 24
Dependent Claim 14 words
The method of claim 15 in which the polymer is a homopolymer of perfluoro-2,2-dimethyl-1,3-dioxole.
Claim 25
Dependent Claim 13 words
The method of claim 15 in which the gases are oxygen and nitrogen.
Claim 26
Dependent Claim 12 words
The method of claim 15 in which the gaseous admixture is air.
Claim 27
Dependent Claim 31 words
The method of claim 15 in which the gases are at least two gases selected from the group consisting of oxygen, nitrogen, hydrogen, helium, methane, ammonia, carbon monoxide and carbon dioxide.
Claim 28
Dependent Claim 12 words
The method of claim 15 in which the gases additionally contain water.
Claim 29
Dependent Claim 19 words
The method of claim 15 in which the membrane has a permeability to oxygen of at least 100 Barrers.
Claim 30
Dependent Claim 16 words
The method of claim 17 in which the permeability to oxygen is at least 200 Barrers.
Claim 31
Dependent Claim 16 words
The method of claim 17 in which the permeability to oxygen is at least 500 Barrers.
Claim 32
Dependent Claim 35 words
A selectively permeable membrane for the separation of gaseous mixtures comprising a film or coating of an amorphous polymer of perfluoro-2,2-dimethyl-1,3-dioxole on a porous support, said membrane exhibiting an oxygen/nitrogen selectively of at least 1.4.
Claim 33
Dependent Claim 35 words
A selectively permeable membrane for the separation of gaseous mixtures comprising a film or coating of an amorphous polymer of perfluoro-2,2-dimethyl-1,3-dioxole on a porous support, said membrane exhibiting an oxygen/nitrogen selectively of at least 1.4.
Claim 34
Dependent Claim 15 words
The membrane of claim 30 having a permeability to oxygen of at least 100 Barrers.
Claim 35
Dependent Claim 16 words
The membrane of claim 31 in which the permeability to oxygen is at least 200 Barrers.
Claim 36
Dependent Claim 16 words
The membrane of claim 31 in which the permeability to oxygen is at least 500 Barrers.
Claim 37
Dependent Claim 15 words
The membrane of claim 31 in which the polymer is a copolymer of perfluoro-2,2-dimethyl -1,3-dioxole.
Claim 38
Dependent Claim 38 words
The membrane of claim 34 in which the polymer is a copolymer of perfluoro-2,2-dimethyl -1,3-dioxole and a complementary amount of at least one monomer selected from the group consisting of tetrafluoroethylene, perfluoromethyl vinyl ether, vinylidene fluoride and chlorotrifluoroethylene.
Claim 39
Dependent Claim 21 words
The membrane of claim 35 in which the polymer is a dipolymer of perfluoro-2,2-dimethyl -1,3-dioxole and a complementary amount of tetrafluoroethylene.
Claim 40
Dependent Claim 30 words
The membrane of claim 36 in which the polymer is a dipolymer containing 65-99 mole % of perfluoro-2,2- dimethyl-1,3-dioxole and having a glass transition temperature of at least 140° C.
Claim 41
Dependent Claim 12 words
The membrane of claim 30 in which the membrane is monolithic membrane.
Claim 42
Dependent Claim 17 words
The membrane of claim 30 in which the membrane is in the form of a hollow fibre.
Claim 43
Dependent Claim 18 words
The membrane of claim 30 in which the film or coating and the porous support are different polymers.
Claim 44
Dependent Claim 15 words
The membrane of claim 30 in which the polymer is a homopolymer of perfluoro-2,2-dimethyl -1,3-dioxole.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-09-23 1995-03-25 1995-09-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-09-23 1999-03-25 1999-09-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-09-23 2003-03-25 2003-09-24 $7700.00 Window Closed / Lapsed

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