Asymmetric Gas Separation Membranes with Superior Capabilities for Gas Separation

• US 20080143014A1
• Filed: 12/18/2006
• Published: 06/19/2008
• Est. Priority Date: 12/18/2006
• Status: Abandoned Application

• Current Assignee: UOP Llc (Honeywell International Inc.)
• Original Assignee: UOP Llc (Honeywell International Inc.)
• Inventors: Tang, Man-Wing
• Application Number:
  US11/612,412
• Publication Number:
  US 20080143014A1
• Time in Patent Office: Days
• US Class Current: 264/216
• CPC Class Codes: B01D 2323/283 Reducing the pores
• CPC Class Codes: B01D 2325/022 Asymmetric membranes
• CPC Class Codes: B01D 2325/0233 with clearly distinguishable layers
• CPC Class Codes: B01D 53/228 characterised by specific membranes
• CPC Class Codes: B01D 67/0011 Casting solutions therefor
• CPC Class Codes: B01D 67/0083 Thermal after-treatment
• CPC Class Codes: B01D 67/0088 Physical treatment with compounds, e.g. swelling, coating or impregnation
• CPC Class Codes: B01D 71/18 Mixed esters, e.g. cellulose acetate-butyrate
• CPC Class Codes: B01D 71/64 Polyimides; Polyamide-imides; Polyester-imides; Polyamide acids or similar polyimide precursors
• CPC Class Codes: B01D 71/643 Polyether-imides
• CPC Class Codes: B01D 71/68 Polysulfones; Polyethersulfones
• CPC Class Codes: B29C 41/24 for making articles of indefinite length
• CPC Class Codes: B29K 2001/00 Use of cellulose, modified cellulose or cellulose derivatives, e.g. viscose, as moulding material
• CPC Class Codes: B29K 2001/12 Cellulose acetate
• CPC Class Codes: B29K 2079/08 PI, i.e. polyimides or derivatives thereof
• CPC Class Codes: B29K 2081/06 PSU, i.e. polysulfones; PES, i.e. polyethersulfones or derivatives thereof
• CPC Class Codes: C08K 5/1565 Five-membered rings
• CPC Class Codes: C08K 5/3415 Five-membered rings
• CPC Class Codes: Y02P 20/129 Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines

Abstract

This invention relates to a method of making flat sheet asymmetric membranes, including cellulose diacetate/cellulose triacetate blended membranes, polyimide membranes, and polyimide/polyethersulfone blended membranes by formulating the polymer or the blended polymers dopes in a dual solvent mixture containing 1,3 dioxolane and a second solvent, such as N,N′-methylpyrrolidinone (NMP). The dopes are tailored to be closed to the point of phase separation with or without suitable non-solvent additives such as methanol, acetone, decane or a mixture of these non-solvents. The flat sheet asymmetric membranes are cast by the phase inversion processes using water as the coagulation bath and annealing bath. The dried membranes are coated with UV curable silicone rubber. The resulting asymmetric membranes exhibit excellent permeability and selectivity compared to the intrinsic dense film performances.

Claims

1. A method for making an asymmetric gas separation membrane, which method comprises:

forming a solution of at least one polymer, by dissolving said polymer in a solvent mixture of 1,3 dioxolane solvent and a second solvent wherein said casting solution contains a ratio of 1,3 dioxolane to said second solvent of from about 1 to 1 to about 99;

1;

quenching the casting solution into a cold water gelation bath at a temperature between about 0° and

25°

C.;

densifying the skin of a resulting asymmetric membrane in a warm water bath between about 25° and

100°

C.; and

removing water from said membrane casting said solution to form a film.

2. The method of claim 1 wherein said second solvent is a solvent selected from the group consisting of N-methylpyrrolidone, N,N′

-dimethylacetamide, dimethylformamide or mixtures thereof.

3. The method of claim 2 wherein said second solvent is N,N′

-methylpyrrolidinone.

4. The method of claim 1 wherein said at least one polymer is selected from the group consisting of polysulfones, sulfonated polysulfones;

polyethersulfones, sulfonated polyethersulfones, polyethers, polyetherimides;

poly(styrenes);

styrene-containing copolymers selected from the group consisting of acrylonitrilestyrene copolymers, styrene-butadiene copolymers and styrene-vinylbenzylhalide copolymers;

polycarbonates;

cellulosic polymers selected from the group consisting of as cellulose acetate, cellulose triacetate, cellulose acetate-butyrate, cellulose propionate, ethyl cellulose, methyl cellulose, and nitrocellulose;

polyamides;

polyimides;

polyamide/imides;

polyketones, polyether ketones;

poly(arylene oxides);

poly(phenylene oxide) and poly(xylene oxide);

poly(esteramide-diisocyanate);

polyurethanes;

polyesters;

polysulfides;

poly(ethylene), poly(propylene), poly(butene-1), poly(4-methyl pentene-1), polyvinyls, e.g., poly(vinyl chloride), poly(vinyl fluoride), poly(vinylidene chloride), poly(vinylidene fluoride), poly(vinyl alcohol), poly(vinyl esters);

poly(vinyl acetate);

poly(vinyl propionate), poly(vinyl pyridines), poly(vinyl pyrrolidones), poly(vinyl ethers), poly(vinyl ketones), poly(vinyl aldehydes);

poly(vinyl formal);

poly(vinyl butyral);

poly(vinyl amides), poly(vinyl amines), poly(vinyl urethanes), poly(vinyl ureas), poly(vinyl phosphates), and poly(vinyl sulfates);

polyallyls;

poly(benzobenzimidazole);

polyhydrazides;

polyoxadiazoles;

polytriazoles;

poly (benzimidazole);

polycarbodiimides;

polyphosphazines;

microporous polymers;

interpolymers, block interpolymers containing repeating units from the above said polymers as terpolymers of acrylonitrile-vinyl bromide-sodium salt of para-sulfophenylmethallyl ethers; and

grafts and blends of said polymers.

5. The method of claim 1 wherein said at least one polymer is selected from the group consisting of polysulfones, sulfonated polysulfones, polyethersulfones (PESs), sulfonated PESs, polyethers, polyetherimides, cellulosic polymers wherein said cellulosic polymers are cellulose acetate or cellulose triacetate;

polyamides;

polyimides, poly(3,3′

,4,4′

-benzophenone tetracarboxylic dianhydride-pyromellitic dianhydride-3,3′

,5,5′

-tetramethyl-4,4′

-methylene dianiline) (poly(BTDA-PMDA-TMMDA)), poly(3,3′

,4,4′

-benzophenone tetracarboxylic dianhydride-pyromellitic dianhydride-4,4′

-oxydiphthalic anhydride-3,3′

,5,5′

-tetramethyl-4,4′

-methylene dianiline) (poly(BTDA-PMDA-ODPA-TMMDA)), poly(3,3′

,4,4′

-diphenylsulfone tetracarboxylic dianhydride-3,3′

,5,5′

-tetramethyl-4,4′

-methylene dianiline) (poly(DSDA-TMMDA)), poly(3,3′

,4,4′

-benzophenone tetracarboxylic dianhydride-3,3′

,5,5′

-tetramethyl-4,4′

-methylene dianiline) (poly(BTDA-TMMDA)), poly(3,3′

,4,4′

-diphenylsulfone tetracarboxylic dianhydride-pyromellitic dianhydride-3,3′

,5,5′

-tetramethyl-4,4′

-methylene dianiline) (poly(DSDA-PMDA-TMMDA)), poly[2,2′

-bis-(3,4-dicarboxyphenyl)hexafluoropropane dianhydride-1,3-phenylenediamine] (poly(6FDA-m-PDA)), poly[2,2′

-bis-(3,4-dicarboxyphenyl)hexafluoropropane dianhydride-1,3-phenylenediamine-3,5-diaminobenzoic acid)] (poly(6FDA-m-PDA-DABA)), polyamide/imides mixtures;

polyketones, polyether ketones; and

microporous polymers.

6. The method of claim 1 wherein said at least one polymer is selected from the group consisting of polyethersulfones, polyimides such as Matrimid®

, P84®

, and poly(3,3′

,4,4′

-diphenylsulfone tetracarboxylic dianhydride-3,3′

,5,5′

-tetramethyl-4,4′

-methylene dianiline), polyetherimides such as Ultem®

, polysulfones, cellulose acetate, cellulose triacetate, poly(vinyl alcohol)s, and microporous polymers.

7. The method of claim 1 wherein said solution further comprises at least one non-solvent selected from the group consisting of methanol, ethanol, isopropanol, acetone, methylethylketone, lactic acid, maleic acid, malic acid, decane, dodecane, nonane, and octane.

8. The method of claim 1 wherein said solution further comprises a non-solvent comprising a mixture of methanol and methylethylketone.

9. The method of claim 1 further comprising coating the surface of the membrane with a thermally curable or UV curable polysiloxane.

10. The method of claim 1 wherein said membrane is densified at a temperature between about 80°

and 86°

C.

11. A casting dope useful for preparation of asymmetric membranes wherein said casting dope comprises a mixture of at least one polymer, a solvent mixture comprising 1,3 dioxolane and a second solvent and at least one nonsolvent.

12. The casting dope of claim 11 wherein said second solvent is a solvent selected from the group consisting of N-methylpyrrolidone, N,N′

-dimethylacetamide, dimethylformamide or mixtures thereof.

13. The casting dope of claim 12 wherein said second solvent is N,N′

-methylpyrrolidinone.

14. The casting dope of claim 11 wherein said at least one polymer is selected from the group consisting of polysulfones, sulfonated polysulfones;

polyethersulfones, sulfonated polyethersulfones, polyethers, polyetherimides;

poly(styrenes);

styrene-containing copolymers selected from the group consisting of acrylonitrilestyrene copolymers, styrene-butadiene copolymers and styrene-vinylbenzylhalide copolymers;

polycarbonates;

cellulosic polymers selected from the group consisting of as cellulose acetate, cellulose triacetate, cellulose acetate-butyrate, cellulose propionate, ethyl cellulose, methyl cellulose, and nitrocellulose;

polyamides;

polyimides;

polyamide/imides;

polyketones, polyether ketones;

poly(arylene oxides);

poly(phenylene oxide) and poly(xylene oxide);

poly(esteramide-diisocyanate);

polyurethanes;

polyesters;

polysulfides;

poly(ethylene), poly(propylene), poly(butene-1), poly(4-methyl pentene-1), polyvinyls, e.g., poly(vinyl chloride), poly(vinyl fluoride), poly(vinylidene chloride), poly(vinylidene fluoride), poly(vinyl alcohol), poly(vinyl esters);

poly(vinyl acetate);

poly(vinyl propionate), poly(vinyl pyridines), poly(vinyl pyrrolidones), poly(vinyl ethers), poly(vinyl ketones), poly(vinyl aldehydes);

poly(vinyl formal);

poly(vinyl butyral);

poly(vinyl amides), poly(vinyl amines), poly(vinyl urethanes), poly(vinyl ureas), poly(vinyl phosphates), and poly(vinyl sulfates);

polyallyls;

poly(benzobenzimidazole);

polyhydrazides;

polyoxadiazoles;

polytriazoles;

poly (benzimidazole);

polycarbodiimides;

polyphosphazines;

microporous polymers;

interpolymers, block interpolymers containing repeating units from the above said polymers as terpolymers of acrylonitrile-vinyl bromide-sodium salt of para-sulfophenylmethallyl ethers; and

grafts and blends of said polymers.

15. The casting dope of claim 11 wherein said at least one polymer is selected from the group consisting of polysulfones, sulfonated polysulfones, polyethersulfones (PESs), sulfonated PESs, polyethers, polyetherimides, cellulosic polymers wherein said cellulosic polymers are cellulose acetate or cellulose triacetate;

polyamides;

polyimides, poly(3,3′

,4,4′

-benzophenone tetracarboxylic dianhydride-pyromellitic dianhydride-3,3′

,5,5′

-tetramethyl-4,4′

-methylene dianiline) (poly(BTDA-PMDA-TMMDA)), poly(3,3′

,4,4′

-benzophenone tetracarboxylic dianhydride-pyromellitic dianhydride-4,4′

-oxydiphthalic anhydride-3,3′

,5,5′

-tetramethyl-4,4′

-methylene dianiline) (poly(BTDA-PMDA-ODPA-TMMDA)), poly(3,3′

,4,4′

-diphenylsulfone tetracarboxylic dianhydride-3,3′

,5,5′

-tetramethyl-4,4′

-methylene dianiline) (poly(DSDA-TMMDA)), poly(3,3′

,4,4′

-benzophenone tetracarboxylic dianhydride-3,3′

,5,5′

-tetramethyl-4,4′

-methylene dianiline) (poly(BTDA-TMMDA)), poly(3,3′

,4,4′

-diphenylsulfone tetracarboxylic dianhydride-pyromellitic dianhydride-3,3′

,5,5′

-tetramethyl-4,4′

-methylene dianiline) (poly(DSDA-PMDA-TMMDA)), poly[2,2′

-bis-(3,4-dicarboxyphenyl)hexafluoropropane dianhydride-1,3-phenylenediamine] (poly(6FDA-m-PDA)), poly[2,2′

-bis-(3,4-dicarboxyphenyl)hexafluoropropane dianhydride-1,3-phenylenediamine-3,5-diaminobenzoic acid)] (poly(6FDA-m-PDA-DABA)), polyamide/imides mixtures;

polyketones, and polyether ketones.

16. The casting dope of claim 11 wherein said at least one polymer is selected from the group consisting of polyethersulfones, polyimides, polyetherimides, polysulfones, cellulose acetate, cellulose triacetate, and poly(vinyl alcohol)s.

17. The casting dope of claim 11 wherein said solution further comprises at least one non-solvent selected from the group consisting of methanol, ethanol, isopropanol, acetone, methylethylketone, lactic acid, maleic acid, malic acid, decane, dodecane, nonane, and octane.

18. The casting dope of claim 11 wherein said solution further comprises a non-solvent comprising a mixture of methanol and methylethylketone.