Catalytic gasification of coal using eutectic salts: reaction kinetics for hydrogasification using binary and ternary eutectic catalysts

A kinetic study of the hydrogasification of Illinois #6 coal was carried out using a ternary (43.5 mol% Li2CO3-31.5 mol% Na2CO3-25 mol% K2CO3) and a binary (29 mol% Na2CO3-71 mol% K2CO3) eutectic system. Hydrogasification experiments were carried out in a high-pressure, high-temperature differential fixed-bed gasifier unit to evaluate the product inhibition effect of H2 on the overall steam gasification kinetics. The overall gasification rate was found to decrease with an increase in the H2 partial pressure. It was also found that starting with a smaller average particle size of sample gave higher overall gasification rates. A rate expression of the Langmuir-Hinshelwood type was then used to satisfy the experimental data at different H2 partial pressures up to carbon conversion of 85–90%.