Enhanced Benzyl Alcohol Oxidation Coupled with Hydrogen Evolution by Co3O4@SS Electrocatalytic Membrane Structured Reactor via Flow-Through Operation

An electrocatalytic membrane structured reactor with a stainless steel membrane as the Co3O4 catalyst carrier (Co3O4@SS EMSR) has been fabricated for benzyl alcohol oxidation coupled with hydrogen evolution. The structural characterization shows that the Co3O4 catalyst with the average size of 20 nm has been immobilized in the membrane pores. The electrochemical characterization indicates that the electrochemical active surface area can be increased and faster electron transfer can be achieved. During the process of benzyl alcohol oxidation coupled with hydrogen evolution by Co3O4@SS EMSR via flow-through mode, the benzyl alcohol conversion of 99% and the selectivity of benzoic acid of 97.7% with the Faraday efficiency of 95.9% for benzoic acid production can be achieved. The hydrogen production from the experiments is approximately consistent with the theoretically calculated hydrogen production, and a Faraday efficiency of 99% for hydrogen evolution can be achieved. The cell voltage during benzyl alcohol oxidation coupled with hydrogen evolution under the flow-through mode is reduced by 850 mV, and energy consumption is reduced by 2.03 kWh NmH2–3 under the condition of a current density of 2.6 mA cm–2, compared with those of hydrogen production by water electrolysis with the oxygen evolution reaction.