On the utilization of coal samples in direct carbon solid oxide fuel cell technology

Coal samples with 3 wt.% ash were chosen as a prospective solid fuel for direct carbon solid oxide fuel cells operating within a temperature range of 600-850 °C. Based upon X-ray and infrared spectroscopy analysis, it was found that the main inorganic impurities in this coal were dolomites. The chemical analysis of ash content in the coal, before and after 3 M HNO3 treatment, indicated that the applied purification procedure allowed a considerable decrease in the ash down to 0.4 wt.% in the coal samples. The physicochemical properties of raw and modified coal samples were investigated by analytical and physicochemical methods in order to evaluate its potential use as a solid fuel for a direct carbon fuel cell with a solid oxide electrolyte (DC-SOFC). The tests indicated that DC-SOFCs fed with this type of processed fossil coal were characterized by stable operation with reasonable current and power densities.