The activity and selectivity of iron-based slurry-phase catalysts were investigated for the hydrogenation of pyrene and the hydrocracking of C-C bonds in several model compounds : 1-methylnaphthalene (1-MN), 2-hexylnaphthalene (2-HN) and 4-(1-naphthylmethyl)bibenzyl (NMBB). Reactions were performed under typical coal liquefaction conditions. Higher reaction temperature and the presence of sulfur increased the hydrogenation of pyrene by the iron catalysts generated in situ. The in situ method of catalyst addition was most effective for pyrene hydrogenation for the. iron catalysts, while molybdenum naphthenate showed increased activity with two-stage processing. Both Fe and Mo catalysts showed low activity in reactions where the catalyst was generated ex situ. Combinations of Fe and Mo catalysts were synergistic for pyrene hydrogenation, although the amount of increase was dependent upon the particular iron precursor used. The Fe and Mo catalysts affected the hydrocracking of the three model species differently. Molybdenum naphthenate was more active for hydrocracking 2-HN and NMBB than any of the Fe catalysts, but combining FeNaph with MoNaph was detrimental to the hydrocracking of these compounds. The selectivity of hydrocracking NMBB at specific bonding sites was affected by the presence and type of catalyst, presence of sulfur, and reaction time.