In order to examine the feasibility of catalyst recovery from liquefaction residue, fundamental study on the properties of catalyst in the residue was carried out by using XRD, SEM/XMA, XAFS and XPS techniques. Residues were obtained from lt/d NEDOL PSU plant which uses Wandoan, Illinois and Wyoming coals as feedstocks and synthetic pyrite as catalyst. Special attention has been paid on the interaction of catalyst with mineral matter and heavy organics in coal. It was found that the catalyst converted to pyrrhotite during liquefaction was covered with organic materials which can be removed by treating with CS2/N-methyl pyrolidinone solvent.
