Methods for electrochemical hydrogenation and methods of forming membrane electrode assemblies

Abstract

A method for electrochemical hydrogenation comprises introducing an organic feed material to an electrochemical cell. The electrochemical cell comprises a membrane electrode assembly comprising an anion exchange membrane, a cathode in electrical contact with a first side of the anion exchange membrane, and an anode in electrical contact with a second side of the anion exchange membrane opposite the first side of the anion exchange membrane. A current passes through the membrane electrode assembly to convert molecules in the organic feed material to a reduced product comprising reduced molecules containing a higher proportion of hydrogen than the organic feed material. A method of forming a membrane electrode assembly comprises forming an ink mixture comprising carbon and a resin, providing droplets of the ink mixture on a substrate to form a decal, and disposing the decal in contact with an anion exchange membrane.

What is claimed is: 
     
         1 . A method for electrochemical hydrogenation, the method comprising:
 introducing an organic feed material to an electrochemical cell, the electrochemical cell comprising a membrane electrode assembly comprising:
 an anion exchange membrane; 
 a cathode in electrical contact with a first side of the anion exchange membrane; and 
 an anode in electrical contact with a second side of the anion exchange membrane opposite the first side of the anion exchange membrane; and 
   passing a current through the membrane electrode assembly to convert molecules in the organic feed material to a reduced product comprising reduced molecules containing a higher proportion of hydrogen than the organic feed material.   
     
     
         2 . The method of  claim 1 , wherein passing a current through the membrane electrode assembly comprises passing a current through the membrane electrode assembly at a temperature of between about 0° C. and about 100° C. 
     
     
         3 . The method of  claim 1 , wherein passing a current through the membrane electrode assembly comprises passing a current through the membrane electrode assembly at a pressure of less than about 1 MPa. 
     
     
         4 . The method of  claim 1 , wherein passing a current through the membrane electrode assembly comprises passing hydroxide ions through the anion exchange membrane from the cathode to the anode. 
     
     
         5 . The method of  claim 1 , wherein introducing the organic feed material comprises flowing the organic feed material continuously into the electrochemical cell. 
     
     
         6 . The method of  claim 1 , wherein introducing the organic feed material comprises introducing the organic feed material to a chamber in fluid communication with the cathode. 
     
     
         7 . The method of  claim 1 , wherein introducing an organic feed material to an electrochemical cell comprises introducing the organic feed material to an electrochemical cell comprising a cathode comprising polytetrafluoroethylene. 
     
     
         8 . The method of  claim 1 , wherein introducing an organic feed material to an electrochemical cell comprises introducing the organic feed material to an electrochemical cell comprising an anion exchange membrane comprising a polymer functionalized with one or more amines. 
     
     
         9 . The method of  claim 1 , wherein introducing an organic feed material to an electrochemical cell comprises introducing the organic feed material to an electrochemical cell comprising an anion exchange membrane comprising one or more fluorinated polymers or one or more chlorinated polymers. 
     
     
         10 . The method of  claim 1 , wherein passing a current through the membrane electrode assembly to convert molecules in the organic feed material to a reduced product comprises generating hydrogen proximate the cathode. 
     
     
         11 . The method of  claim 1 , wherein passing a current through the membrane electrode assembly to convert molecules in the organic feed material to a reduced product comprises generating hydrogen from water proximate the cathode. 
     
     
         12 . The method of  claim 1 , wherein introducing an organic feed material to an electrochemical cell comprises introducing the organic feed material to an electrochemical cell comprising a cathode comprising a hydrophobic material. 
     
     
         13 . A method of forming a membrane electrode assembly, comprising:
 forming an ink mixture comprising carbon, a resin, and polytetrafluoroethylene;   providing droplets of the ink mixture on a substrate to form a decal; and   disposing the decal in contact with an anion exchange membrane.   
     
     
         14 . The method of  claim 13 , wherein forming an ink mixture comprises forming a mixture comprising the carbon, the resin, and water. 
     
     
         15 . The method of  claim 13 , wherein forming an ink mixture comprises forming a mixture having a weight ratio of the carbon to the resin from about 2:1 to about 10:1. 
     
     
         16 . The method of  claim 13 , wherein providing droplets of the ink mixture on a substrate comprises providing droplets of the ink mixture having a volume between about 1 μL and about 20 μL. 
     
     
         17 . The method of  claim 13 , further comprising air-drying the droplets of the ink mixture. 
     
     
         18 . The method of  claim 13 , wherein disposing the decal in contact with an anion exchange membrane comprises hot-pressing the decal against the anion exchange membrane. 
     
     
         19 . The method of  claim 18 , wherein hot-pressing comprises applying a pressure of at least 1 MPa to the decal. 
     
     
         20 . The method of  claim 18 , wherein hot-pressing comprises maintaining the decal and the anion exchange membrane at a temperature of between 90° C. and 120° C. 
     
     
         21 . The method of  claim 13 , further comprising:
 forming a second decal; and   disposing the second decal in contact with the anion exchange membrane at a surface on an opposite side of the anion exchange membrane as the decal.