Generalized Kinetic Model of Catalyzed Hydroliquefaction of Coal Incorporating Tetralin Dehydrogenation Reaction

A three-component kinetic model previously reported for uncatalyzed liquefaction has been used to simulate hydroliquefaction of Victorian brown coal with three different types of catalysts: iron-tin, iron, and haematite. The presence of catalyst is found to enhance hydrogenation of coal as well as the equilibrium hydrogenation-dehydrogenation reactions involving donor solvent. The thermal dissolution and autohydrogenation reaction rates are independent of catalyst used. Iron-tin-based catalyst has been found to be most effective for the hydrogenation reaction step. The simulation shows that the reactions producing hydrogen from tetralin are much slower than the coal-hydrogen reactions; hence, efforts aimed at efficient abstraction of hydrogen from the hydrogen donors may be beneficial.