Electrochemical Hydrogenation Using Membrane Reactors

Hydrogenation is one of the most crucial and widespread chemical processes. This review addresses the rapidly developing electrochemical hydrogenation technology using membrane reactors. A membrane acts simultaneously as a cathode for the electrochemical formation of hydrogen and a separator dividing the electrochemical compartment from the hydrogenation compartment with a substrate. Electrochemical membrane hydrogenation allows producing high-purity hydrogen directly from water, avoiding catalyst poisoning. In this case, hydrogen reaches the membrane surface in the hydrogenation compartment in a highly active atomic state. The choice of catalyst and process conditions enables one to tune selectivity of the process, and the separation of chemical processes occurring in the system can make it possible to eliminate the stage of products purification from at least some of the starting compounds and solvents. The various types of membranes that can be used in this technology are considered, as well as the processes of electrochemical hydrogenation of various organic and inorganic compounds in membrane reactors, including the processes of electrolytic hydrogen production and the operation of fuel cells. In conclusion, the prospects for the development of this technology are discussed.