Study on hydro-liquefaction kinetics of thermal dissolution soluble fraction from Shenfu sub-bituminous coal

•TDSF is almost completely liquefied at 380°C with high yield of oil+gas.•The model of hydro-liquefaction of TDSF includes series and parallel reactions.•The regressive reaction is ruled out in the model.•TDSF to PA and PA to oil+gas are the main reactions.•Oil+gas are mainly formed from the reaction of PA to oil+gas. Thermal dissolution (TD) of coal and hydro-liquefaction of the thermal dissolution soluble fraction (TDSF) with a high activity catalyst is one of effective high efficient hydro-liquefaction of coal techniques. In this study, a Chinese Shenfu (SF) sub-bituminous coal was thermally dissolved, and the TDSF obtained was further hydro-liquefied with Ni–Mo-S/Al2O3 catalyst. Based on the hydro-liquefaction results, a model including series and parallel reactions was established for the hydro-liquefaction of TDSF catalyzed by Ni–Mo-S/Al2O3, and the regressive reactions were ruled out in the model. From the kinetic parameters calculated, it suggested that the regressive reactions including the char formation reactions were negligible in the hydro-liquefaction of TDSF catalyzed by Ni–Mo-S/Al2O3. The reactions of TDSF to preasphaltene and preasphaltene to oil+gas predominated the formation of oil+gas. Ni–Mo-S/Al2O3 could decrease the activation energy of preasphaltene to oil+gas reaction, thus promoting the formation of oil and gas in the catalytic hydro-liquefaction of TDSF.