Effect of Steam Partial Pressure on Gasification Rate and Gas Composition of Product Gas from Catalytic Steam Gasification of HyperCoal

HyperCoal was produced from coal by a solvent extraction method. The effect of the partial pressure of steam on the gasification rate and gas composition at temperatures of 600, 650, 700, and 750 °C was examined. The gasification rate decreased with decreasing steam partial pressure. The reaction order with respect to steam partial pressure was between 0.2 and 0.5. The activation energy for the K2CO3-catalyzed HyperCoal gasification was independent of the steam partial pressure and was about 108 kJ/mol. The gas composition changed with steam partial pressure and H2 and CO2 decreased and CO increased with decreasing steam partial pressure. By changing the partial pressure of the steam, the H2/CO ratio of the synthesis gas can be controlled.