Production of syngas by solid oxide electrolysis: A case study

An investigation of syngas production using solid oxide electrolysis was carried out. Aconventional solid oxide cell based on Ni supporting cathode, thin yttria-stabilized zirconiaelectrolyte, yttria-doped ceria interlayer, and strontium-doped lanthanum cobaltite andferrite-based perovskite anode (Ni-YSZ/YSZ/YDC/LSFC) was used for the reduction of CO2and water to syngas. This process was assisted by H2 added to the reactant in variousamounts to maintain the Ni sites in a metallic state. This was necessary to favour CO2reaction and to avoid ohmic constraints that may derive from the occurrence of Ni reoxidationas consequence of the presence of oxidising species like CO2 and water. Theoutlet gas was analysed by gas chromatography. The presence of CO and CH4 beside CO2and H2 was detected in the outlet stream. Analysis of outlet gas composition revealed thatCO was produced by both electrochemical and catalytic mechanisms. Suitable CO2 conversionwas achieved using dry gas.