Catalytic Activity of FeMoNi Ternary Sulfide Supported on a Nanoparticulate Carbon in the Liquefaction of Indonesian Coals

Abstract

A series of ternary sulfide catalysts of Fe, Mo, and Ni supported on a nanoparticulate carbon, Ketjen Black (KB), have been shown to be as active as sulfided Mo and Ni catalysts containing significantly greater quantities of Mo for the liquefaction of some Indonesian coals. Thus, it is possible to retain a high catalytic activity when replacing some expensive Mo by cheap Fe. Under the reaction conditions of 450 °C and 15 MPa of H2 pressure at solvent (tetralin)/coal/catalyst weight ratios of 1/1/0.03, FeMoNi catalyst (10% Fe, 5% Mo, and 2% Ni based on KB) provided an oil yield (wt %, daf) of 77% from liquefaction of Tanito Harum coal that is comparable to that obtained with NiMo (2% Ni and 10% Mo) supported on KB. It is found that Fe-based KB catalysts have the high activity even with a smaller amount of expensive Mo. The activity of the catalyst for hydrogenation of 1-methylnaphthalene appeared to reflect the Mo content in the combination of Fe, Mo, and Ni on KB. The activity of FeMoNi/KB catalysts is slightly influenced by the order of metal impregnation sequences in the catalyst preparation procedure. The repeated use of the catalyst, recovered as a tetrahydrofuran-insoluble fraction including ash and unconverted coal, still provided high oil yield, suggesting that bottom recycle may markedly reduce the amount of catalyst used in the coal liquefaction.