“…The following items have been investigated in this study: (1) comparison of the hydrogenation reactivity of the recycled solvents derived from Illinois No. 6, Battle River, and Wandoan coals, obtained from a 1t/day PDU; (2) characteristics changes of the solvents during storage and the influence of catalytic activities on hydrogenation; (3) a comparision of catalyst performance on hydrogenation between newly developed and commercial catalysts, based on the result of storage stability test.…”