Membranes for gas separation

Abstract

Membranes, methods of making the membranes, and methods of using the membranes are described. The membranes can comprise a support layer, and a selective polymer layer disposed on the support layer. The selective polymer layer can comprise an oxidatively stable carrier dispersed within a hydrophilic polymer matrix. The oxidatively stable carrier can be chosen from a quaternary ammonium hydroxide carrier (e.g., a mobile carrier such as a small molecule quaternary ammonium hydroxide, or a fixed carrier such as a quaternary ammonium hydroxide-containing polymer), a quaternary ammonium fluoride carrier (e.g., a mobile carrier such as a small molecule quaternary ammonium fluoride, or a fixed carrier such as a quaternary ammonium fluoride-containing polymer), and combinations thereof. The membranes can exhibit selective permeability to gases. The membranes can selectively remove carbon dioxide and/or hydrogen sulfide from hydrogen and/or nitrogen. Further, the membranes can exhibit oxidative stability at temperatures above 100° C.

1 . A membrane comprising:
 a support layer; and   a selective polymer layer disposed on the support layer, the selective polymer layer comprising an oxidatively stable carrier dispersed within a hydrophilic polymer matrix,   wherein the oxidatively stable carrier is chosen from a quaternary ammonium hydroxide carrier, a quaternary ammonium fluoride carrier, and combinations thereof.   
     
     
         2 . The membrane of  claim 1 , wherein the quaternary ammonium hydroxide carrier is chosen from a small molecule quaternary ammonium hydroxide, a quaternary ammonium hydroxide-containing polymer, and combinations thereof. 
     
     
         3 . The membrane of  claim 2 , wherein the oxidatively stable carrier comprises a small molecule quaternary ammonium hydroxide chosen from tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, and combinations thereof. 
     
     
         4 . The membrane of  claim 2 , wherein the oxidatively stable carrier comprises a quaternary ammonium hydroxide-containing polymer chosen from poly(diallyldimethyl-ammonium hydroxide), poly(vinylbenzyltrimethylammonium hydroxide), poly(2-vinyl-1-methylpyridinium hydroxide), poly(acrylamide-N-propyltrimethylammonium hydroxide), poly(2-methacryloxyethyltrimethylammonium hydroxide), poly(3-chloro-2-hydroxypropyl-2-methacryloxyethyldimethylammonium hydroxide), copolymers thereof, and blends thereof. 
     
     
         5 . The membrane of  claim 1 , wherein the quaternary ammonium fluoride carrier is chosen from a small molecule quaternary ammonium fluoride, a quaternary ammonium fluoride-containing polymer, and combinations thereof. 
     
     
         6 . The membrane of  claim 5 , wherein the oxidatively stable carrier comprises a small molecule quaternary ammonium fluoride chosen from tetramethylammonium fluoride, tetraethylammonium fluoride, tetrapropylammonium fluoride, tetrabutylammonium fluoride, cesium fluoride, potassium fluoride, sodium fluoride, lithium fluoride, and combinations thereof. 
     
     
         7 . The membrane of  claim 5 , wherein the oxidatively stable carrier comprises a quaternary ammonium fluoride-containing polymer chosen from poly(diallyldimethyl-ammonium fluoride), poly(vinylbenzyltrimethylammonium fluoride), poly(2-vinyl-1-methylpyridinium fluoride), poly(acrylamide-N-propyltrimethylammonium fluoride, poly(2-methacryloxyethyltrimethylammonium fluoride), poly(3-chloro-2-hydroxypropyl-2-methacryloxyethyldimethylammonium fluoride), copolymers thereof, and blends thereof. 
     
     
         8 . The membrane of  claim 1 , wherein the hydrophilic polymer matrix comprises a crosslinked hydrophilic polymer. 
     
     
         9 . The membrane of  claim 1 , wherein the hydrophilic polymer matrix comprises polyvinyl alcohol. 
     
     
         10 . The membrane of  claim 1 , wherein the hydrophilic polymer matrix comprises polyvinyl alcohol-polysiloxane. 
     
     
         11 . The membrane of  claim 1 , wherein the support layer comprises a gas permeable polymer. 
     
     
         12 . The membrane of  claim 11 , wherein the gas permeable polymer comprises a polymer chosen from polyamides, polyimides, polypyrrolones, polyesters, sulfone-based polymers, polymeric organosilicones, fluorinated polymers, polyolefins, copolymers thereof, and blends thereof. 
     
     
         13 . The membrane of  claim 12 , wherein the gas permeable polymer comprises polyethersulfone or polysulfone. 
     
     
         14 . The membrane of  claim 1 , wherein the support layer comprises a gas permeable polymer disposed on a base. 
     
     
         15 . The membrane of  claim 14 , wherein the base comprises a non-woven fabric. 
     
     
         16 . The membrane of  claim 15 , wherein the non-woven fabric comprises fibers formed from a polyester. 
     
     
         17 . The membrane of  claim 1 , wherein the membrane further comprises a permeable layer disposed between the support layer and the selective polymer layer. 
     
     
         18 . The membrane of  claim 17 , wherein the permeable layer comprises a gas permeable polymer chosen from poly(dimethylsiloxane), poly(trimethylsilylpropyne), poly(4-methyl-1-pentene), copolymers thereof, and blends thereof. 
     
     
         19 . The membrane of  claim 1 , wherein the membrane further comprises a permeable layer disposed on the selective polymer layer. 
     
     
         20 . The membrane of  claim 19 , wherein the permeable layer comprises a gas permeable polymer chosen from poly(dimethylsiloxane), poly(trimethylsilylpropyne), poly(4-methyl-1-pentene), copolymers thereof, and blends thereof. 
     
     
         21 - 33 . (canceled)