Liquid Tin Anode SOFC For Direct Fuel Conversion - Impact of Coal and JP-8 Impurities

Abstract

The Liquid Tin Anode solid oxide fuel cell (LTA-SOFC) has a demonstrated capability for direct fuel conversion using virtually any carbonaceous fuel. Two most notable applications under development are direct logistic fuel JP-8 conversion and direct coal (and biomass) conversion. For example a Gen 3.1 cell using logistic fuel only without fuel processing or reforming, has demonstrated specific power of 170 mW/cm2, at least 30 full thermal cycles and less than 7 minutes start up. Direct logistic fuel or coal conversion without fuel reforming/gasification/purification may also bring contaminants or impurities without fuel value in direct contact with fuel cell components. The tin anode is a fluid and a non-structural cell component so it is tolerant of many impurities. However fuel contaminants dissolved in molten tin could have a critical impact on cell components such as the electrolyte that are in direct contact with the molten tin anode. Certain fuel (V, Mo, etc.) impurities had shown causing damage to fuel cell if they were in direct contact with cell components such as electrolyte. This paper will examine liquid tin (molten tin bath) as a potential media to attenuate/reduce/eliminate harmful coal contaminants, providing a mitigation strategy for reducing a key technical risk factor of direct coal conversion using a fuel cell.