Method and Device for the Electrochemical Utilization of Carbon Dioxide

Abstract

Various embodiments may include an electrolyzer for electrochemical utilization of carbon dioxide comprising: an electrolysis cell defining an anode space and a cathode space; an anode; a cathode; a first cation-permeable membrane disposed between the anode space and the cathode space; and a layer comprising an anion-selective polymer disposed between the first membrane and the cathode. The anode directly adjoins the first cation-permeable membrane and the layer covers at least part of the cathode but not all of the cathode.

What is claimed is: 
     
         1 . An electrolyzer for electrochemical utilization of carbon dioxide, the electrolyzer comprising:
 an electrolysis cell defining   an anode space and a cathode space;   an anode in the anode space;   a cathode in the cathode space;   a first cation-permeable membrane disposed between the anode space and the cathode space;   wherein the anode directly adjoins the first cation-permeable membrane; and   a layer comprising an anion-selective polymer disposed between the first cation-permeable membrane and the cathode;   wherein the layer covers at least part of the cathode but not all of the cathode.   
     
     
         2 . The electrolyzer as claimed in  claim 1 , wherein the layer covers a surface area of the first membrane within a range from 20% to 85%. 
     
     
         3 . The electrolyzer as claimed in  claim 1 , wherein the cathode comprises at least one element selected from the group consisting of: silver, copper, lead, indium, tin, and zinc. 
     
     
         4 . The electrolyzer as claimed in  claim 1 , wherein the cathode comprises a gas diffusion electrode. 
     
     
         5 . A method of operating an electrolyzer for electrochemical utilization of carbon dioxide, the method comprising:
 decomposing carbon dioxide at a cathode disposed in a cathode space of an electrolysis cell;   forming at least one of carbonate and hydrogencarbonate from unconverted carbon dioxide and hydroxide ions at the cathode;   transporting hydrogen ions from an anode disposed in an anode space of the electrolysis cell through a first cation-permeable membrane disposed between the anode space and the cathode space;   wherein the anode directly adjoins the first cation-permeable membrane and a layer comprising an anion-selective polymer is disposed between the first cation-permeable membrane and the cathode;   reacting the hydrogen ions and the at least one of carbonate or hydrogencarbonate to produce carbon dioxide and water in a contact region of the layer and the first cation-permeable membrane; and   releasing the carbon dioxide through flow channels and/or pores in the layer.   
     
     
         6 . The method as claimed in  claim 5 , wherein the electrolyzer is operated with pure water. 
     
     
         7 . The method as claimed in  claim 5 , further comprising producing at least one of carbon monoxide, ethylene, or formic acid. 
     
     
         8 . (canceled)