Direct Toluene Electro-hydrogenation Using Anion Exchange Membrane Electrolyzer

Abstract

Direct toluene electro-hydrogenation is gaining considerable attention for storing and transporting large amounts of energy. When a proton exchange membrane (PEM) is used in this system, dragged water molecules migrate with the protons from the anode to the cathode, and water inhibits the toluene hydrogenation reaction at the cathode. An anion exchange membrane (AEM) is expected to facilitate the migration of water from the cathode to the anode, and less water suppresses the side reactions. In this study, the quantity of water reaching the cathode is determined. Further, direct toluene electro-hydrogenation without side reactions except hydrogen generation is successfully performed using the AEM. Moreover, optimization of the catalyst loading results in an improved current efficiency exceeding 1.5 mg cm−2. This technology is valuable as a first step in direct toluene electro-hydrogenation using AEM.

Keywords

• toluene/methylcyclohexane
• organic hydride
• hydrogenation electrolysis
• anion exchange membrane