(13a) Caustic Aqueous Phase Ethanol Reforming for Process-Intensified Hydrogen Production

Efficient generation of compressed pure hydrogen is a critical milestone for sustaining hydrogen in the energy network. Many of the traditional methods for compressed hydrogen production are hindered by high operating temperature, high energy cost, low efficiency, and many unit operations. The Caustic Aqueous Phase Ethanol Reforming (CAPER) process converts liquid-phase, oxygenated hydrocarbons to high pressure and high purity hydrogen at lower temperatures than traditional methods and using renewable resources. Additionally, the carbon dioxide produced by ethanol oxidation is captured within the caustic electrolyte solution. The electrolyte can be refreshed to release carbon dioxide or bicarbonate in a regenerator unit. Without the need of downstream separation, compression, or membranes, the CAPER process achieves process intensified hydrogen production at high efficiency. Shown in the figure below is the batch reactor for catalyst screening efforts and an overview of the electrochemical process. Ethanol is oxidized to carbon dioxide on the anode and hydrogen is formed at high pressure on the cathode. By operating at high pressure, the reactants remain in liquid phase while the only product gas is compressed hydrogen. The reduced operating potential provides many energy benefits over other electrochemical hydrogen production methods. The results of this work demonstrate a proof of concept of the CAPER technology and provide insights optimizing this system.