Biogas Upgrading Using SOEC with a Ni-ScYSZ Electrode

Abstract

Biogas consists mainly of CH4, CO2 and small amounts of H2S. The value of biogas will increase significantly if it is upgraded to pipeline quality by converting CO2 and H2O in the biogas to CO and H2 using a Solid Oxide Electrolysis Cell (SOEC) followed by methanation. The Ni-ScYSZ-cermet electrode is, however, active for steam reforming of CH4, but sulphur traces in the biogas reduce the steam reforming activity. It is proven that sulphur stops steam reforming activity whereas the electrochemistry is only affected to a limited degree, showing that up-grading of biogas using SOEC with Ni-ScYSZ electrode is feasible.