Ligand structure effect in oil-soluble phosphorus-containing molybdenum precursors for slurry-phase hydrocracking of heavy oil

Slurry-phase hydrocracking for heavy oil upgrading is a challenging technology in the petroleum refining industry. We prepared various P-containing Mo precursors to elucidate the effect of their ligand structures on the slurry-phase hydrocracking of vacuum residue. Characteristic analyses of the Mo precursors were performed by first determining their dispersibility and decomposition patterns, followed by evaluating the sulfidation degree and morphology of the resulting MoS2 catalyst. The dispersibility of the Mo precursors was evaluated by a method of measuring the solubility parameter based on the oil compatibility model. The slurry-phase hydrocracking results revealed that the H-2 consumption rate, residue conversion, hydrodesulfurization, and asphaltene conversion were dependent on the Mo precursor. The Mo triethylphosphite species, which had the largest number of active sites, was found to be the most efficient precursor for improving product distribution and product quality. (C) 2021 Elsevier Inc. All rights reserved.