Liquid Tin-Lead Anode Solid Oxide Fuel Cell Fueled by Coal

Liquid tin-lead alloy, liquid bismuth, and liquid tin-lead-bismuth alloy were investigated as potential anodes for a solid oxide fuel cell powered directly by coal. Power generation from direct oxidation of solid coal was demonstrated with a good stability only in the case when liquid tin-lead anode was used. The tests were carried out at 900 degrees C under ambient pressure. The open circuit potentials of the SOFC with tin-lead and bismuth anodes operated under nitrogen were compared, and those values were found to correspond to the metal-metal oxide redox potentials for tin and bismuth, respectively. When the SOFCs were fueled by hydrogen, only the tin-lead anode showed a direct electrochemical reaction between hydrogen and oxygen. When 60-mesh coal powder was fed to the liquid tin-lead anode, SOFC showed increase in open circuit potential and generated power from direct electrochemical oxidation of coal.