(621ex) Nano-scaled MoS2 catalysts on the slurry phase hydrocracking of vacuum residue

The oil-dispersible nanoscaled-MoS₂ catalysts were synthesized by a ligand stabilization method using trioctylphosphine oxide (TOPO) as a coordinating solvent and molybdenum hexacarbonyl (Mo(CO)₆)  as a molybdenum precursor. Characterizations made by TEM and EXAFS spectroscopy revealed that the MoS2 formed an oil-dispersible lamella-shaped nanoparticles with lengths of less than 10 nm at 573 K and also resulted in the formation of 3-4 layers of stacks at an elevated sulfidation temperature of 618 K.   The nanoscaled-MoS₂ catalysts gave a good activity for the hydrocracking of vacuum reside with a yield to the liquid oil product of 78.2% at 673 K and 10.0 MPa, which was much higher than the multi-layered MoS₂ catalyst of 52.4%. it was thus demonstrated that the single layered MoS₂ nanocatalyst rather than multi-layered MoS₂ structure was beneficial to the hydrocracking of vacuum residue due to its accessibility towards heavy oil components.