Methanol Synthesis from CO2 and H2O Using a Solid Phosphate Electrolyzer at 240 °C and 28 Bar

Abstract

It has been demonstrated that it is possible to produce methanol in one step in reasonable amounts by electrolysis of CO2 and H2O gasses dissolved under 28 bar and at 240 °C in contact with an electrolyte consisting of solid CsH2PO4 with additions of polyvinyl butyral (PVB) acting as a binder. The cathode was designed as a sandwich with a layer of a copper methanol catalyst and a porous platinum electrode. The anode consisted of porous ruthenium metal covered by a layer of RuO2. The system was operated with current densities of up to ca. 100 mA cm−2 with a voltage of less than 2 volts producing methanol with a Faradaic efficiency of up to ca. 7%. There seems to be nothing against recirculating the rest of reactant gases to improve the conversion. The question is of course whether the present approach can compete with a more traditional conversion starting with electrochemical produced hydrogen.