A novel preparation strategy for an oil-soluble catalyst in slurry phase hydrocracking: Synergistic effect and electronic regulation of Fe on MoS2.

[Display omitted] • Novel strategy for oil-soluble hydrogenation catalysts in slurry phase is proposed. • Insertion of Fe lowers length and stacking layers of MoS 2 slabs by 16.7% and 20.0%. • XPS results prove that Fe transfers electrons to Mo to form electro-rich MoS 2. • FeMoS catalyst with a proper electronic structure has best hydrocracking activity. • Electron-donor effect of Fe on MoS 2 facilitates the H migration and CUS formation. The appropriate electronic structure of catalysts is vital for the slurry phase hydrocracking activity of inferior vacuum residue. Herein, a series of chemically bonded oil-soluble bimetallic FeMo catalysts with excellent performance were prepared by a novel strategy. Both experimental and density functional theory (DFT) calculations were conducted to investigate the regulatory effect of Fe on MoS 2. It was found that the incorporation of Fe can reduce the average length and stacking layers of the MoS 2 catalyst by 16.7% and 20.0%, respectively, thus exposing more active sites. Meanwhile, XPS, Raman and EXAFS results show that Fe transfers electrons to Mo to form electron-rich MoS 2 and generate more defect sites on the surface of the FeMoS catalyst. For the VR hydrocracking activity test, it was demonstrated that the electron-rich MoS 2 catalyst exhibits excellent performance, with the coke yield reduced by 32.0% and the total conversion rate of resin and asphaltene increased by 13.5%. Moreover, DFT results further reveal that the electrons transfer from Fe to Mo induces the change of chemical properties of the MoS 2 surface and the adjustment of the d-band center, which promotes the migration of H and reduces the generation energy of coordinatively unsaturated sites. This study provides valuable insights into the design and upgrading of prominent oil-soluble bimetallic catalysts for slurry phase hydrocracking. [ABSTRACT FROM AUTHOR]