Methane synthesis from CO2 and H2O with electricity using H-permeable membrane electrochemical cells with Ru catalyst and phosphate electrolyte

Abstract

The synthesis of methane from CO₂ and H₂O using a Ru catalyst and water electrolyzer was examined between 210 and 270 °C. A Ru/TiO₂ catalyst, Pd–Ag membrane, CsH₂PO₄/SiP₂O₇ electrolyte, and Pt anode were combined. At 10 mA cm⁻², 0.087 cm_STP³ min⁻¹ CO₂ flow rate, and 270 °C, 93.3% of the current was consumed for methanation and 59% CO₂ conversion was attained. The formation of H₂ and CO as byproducts accounted for 1.7% and 0.33% of the current, respectively, under these conditions. The potential of the proposed method as a power-to-gas technology is discussed.