Fabrication of green polymeric membranes

Patent metadata

Field	Value
Publication number	US-11007487-B2
Application number	US-201615774458-A
Country	US
Kind code	B2
Filing date	Dec 8, 2016
Priority date	Dec 8, 2015
Publication date	May 18, 2021
Grant date	May 18, 2021

Abstract

Provided herein are methods of fabricating membranes using polymers with functionalized groups such as sulfone (e.g., PSf and PES), ether (e.g., PES), acrylonitrile (e.g., PAN), fluoride (e.g., pvdf and other fluoropolymers), and imide (e.g., extem) and ionic liquids. Also provided are membranes made by the provided methods.

First claim

What is claimed is:

1. A method of making a membrane comprising:
preparing a membrane solution by dissolving a polymer in a solvent consisting of an ionic liquid, wherein the polymer is selected from the group consisting of polyvinylidene fluoride-hexafluoropropyl copolymer (PVDFHFP), polyvinylidene fluoride (PVDF), polyvinylfluoride (PVF), polychlorotrifluoroethylene (PCTFE), perfluoroalkoxy polymer (PFA), fluorinated ethylene-propylene (FEP), polyethylenetetrafluoroethylene (ETFE), polyethylenechlorotrifluoroethylene (ECTFE), perfluorinated elastomer [perfluoroelastomer] (FFPM/FFKM), fluorocarbon [chlorotrifluoroethylenevinylidene fluoride] (FPM/FKM), fluoroelastomer [tetrafluoroethylene-propylene] (FEPM), perfluoropolyether (PFPE), perfluorosulfonic acid (PFSA), perfluoropolyoxetane, polyterafluoroethylene (PTFE), polysulfone, polyether sulfone (PES), polyetherimide, polyetherimide sulfone, polycarbonate, polyphenylene sulfide, polystyrene, aromatic polycarbonates, aromatic polyesters, aromatic polyphenylenes, polyxylylenes, polyphenylenevinylenes, polyphenyleneethylenes, and polyaryl ether ketones, or a combination thereof;
wherein the ionic liquid is selected from the group consisting of 1-ethyl-3-methylimidazolium diethyl phosphate ([EMIM]DEP), 1-ethyl-3-methylimidazolium thiocyanate ([EMIM]SCN), l-butyl-3-methylimidazolium chloride, 1-alkyl-3-methylimidazolium, 1-alkylpyridinium, 1-alkylpyridinium chloride, and N-methyl-N-alkylpyrrolidinium;
casting or spinning the membrane solution; and
inducing phase separation by immersing the cast or spun membrane solution in a membrane fabrication bath comprising a poor solvent or a non-solvent, thereby forming the membrane.

2. The method of claim 1 , wherein the poor solvent or non-solvent is selected from the group consisting of glycerin, ethylene glycol, butanediol, propylene glycol, methanol, ethanol, butanol, isopropanol, and water or a combination thereof.

3. The method of claim 1 , wherein the polymer is selected from a combination of one or more of: PVDFHFP, PVDF, PVF, PCTFE, PFA, FEP, ETFE, ECTFE, FFPM/FFKM, FPM/FKM, FEPM, PFPE, PFSA, perfluoropolyoxetane, and PTFE with one or more of polysulfone, PES, polyetherimide, and polyetherimide sulfone.

4. The method of claim 1 , wherein the membrane solution comprises 0.1 to 30 weight percent of the polymer.

5. The method of claim 4 , wherein the membrane solution comprises 10 to 20 weight percent of the polymer.

6. The method of claim 1 , wherein the membrane solution comprises 70 to 99 weight percent of the solvent.

7. The method of claim 1 , wherein the membrane solution further comprises one or more additives selected from the group consisting of metal compounds, inorganic acids, and organic acids.

8. The method of claim 1 , wherein the polymer is PVDFHFP, PVDF, PVF, PCTFE, PFA, FEP, ETFE, ECTFE, FFPM/FFKM, FPM/FKM, FEPM, PFPE, PFSA, perfluoropolyoxetane, or PTFE.

9. The method of claim 1 , wherein the polymer is polyetherimide sulfone.

10. The method of claim 1 , wherein the polymer is polyetherimide, PES, or PVDF.

11. The method of claim 10 , wherein the polymer is PES.

12. The method of claim 9 , wherein the ionic liquid is [EMIM] SCN.

13. The method of claim 10 , wherein the ionic liquid is [EMIM] DEP.

14. The method of claim 1 , further comprising recovering the ionic liquid from the membrane fabrication bath after the membrane has been formed.

15. The method of claim 14 , wherein the membrane fabrication bath consists of water, and recovering the ionic liquid comprises evaporation or adsorbing the water to concentrate the ionic liquid.

Assignees

• Univ King Abdullah Sci & Tech

Inventors

• Kim Dooli
• Pereira Nunes Suzana

Classifications

• B01D67/0016

  Coagulation · CPC title

• B01D2323/08

  Specific temperatures applied · CPC title

• B01D71/64

  Polyimides; Polyamide-imides; Polyester-imides; Polyamide acids or similar polyimide precursors · CPC title

• B01D67/0011 Primary

  Casting solutions therefor · CPC title

• C08J2327/16

  Homopolymers or copolymers of vinylidene fluoride · CPC title