Catalytic activities of NiMo supported on hollow carbon black(Ketjen Black), a commercial NiMo/alumina, and a synthetic pyrite were examined in the single- andtwo-stage liquefaction ofWyoming subbituminous and Yallourn brown coals with tetralin or1-methylnaphthalene. Thetwo-stage liquefaction consisting of lower temperatures (<400
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C) inthe first stage and hightemperatures around 450
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C in the second stage was very effective forthe conversion ofasphaltene and preasphaltene components into oil fractions with thesuppression of gas formation,providing the oil yield above 70 wt %, which was much larger than thatobtained by the singlestage of 450
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C-60 min. The NiMo/KB catalyst exhibited a muchhigher activity for theproduction of the lighter oil fraction in the two-stage liquefactionthan a commercial NiMo/Al
2O
3 and a synthetic pyrite, especially when1-metylnaphthalene of nondonor solvent was used,reflecting the higher activity of NiMo/KB catalyst for thehydrogenation of solvent as well asthe coal at temperatures below 400
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C in the first stage. It isnoted that NiMo/KB catalystgave a high oil yield around 60% even without any solvent in thetwo-stage liquefaction.