Preparation, structural and hydrotreating catalytic properties of unsupported NiRh2S4

Abstract

NiRh₂S₄ unsupported catalysts were prepared by a coprecipitation method and characterized by X-ray diffraction (XRD), chemical analysis, specific surface area measurements and high-resolution transmission electron microscopy (HRTEM). It has been shown by XRD and HRTEM that the main phase of the prepared solids has a cubic spinel type structure. The catalytic properties were evaluated in the hydrodesulfurization (HDS) of thiophene and the hydrogenation (HYD) of tetralin. The intrinsic HDS and HYD activities of the NiRh₂S₄ catalyst were compared with dispersed Rh, Mo binary sulfides and ternary NiMoS and NiCr₂S₄ sulfides. The intrinsic HDS activity of NiRh₂S₄ is higher than the sum of those of the individual Ni₃S₂ and Rh₂S₃ compounds, suggesting the existence of a synergistic effect between Ni and Rh.