Qinghe Yang

NiWO4 nanoparticles: a promising catalyst for hydrodesulfurization

NiWO(4) nanoparticles have been facilely synthesized by a hydrothermal approach, and used as a catalyst for the hydrodesulfurization of thiophene and its derivative 4,6-dimethyldibenzothiophene, showing a significantly higher activity than commercial NiW/Al(2)O(3).

A study on the origin of the active sites of HDN catalysts using alumina-supported MoS3 nanoparticles as a precursor

This article proposes alumina-supported MoS3 nanoparticles (NPs) as a precursor of model catalysts to study hydrodenitrogenation (HDN) catalytic mechanisms. The NPs were first loaded into γ-Al2O3 by a simple chemical deposition method and then thermally treated under H2, N2 and H2S atmospheres, respectively, to obtain three MoS2/Al2O3 catalysts. The XPS, N2 adsorption–desorption and HRTEM characterization results show that using MoS3 NPs instead of conventional MoOx NPs as the precursor can effectively tune the edge composition of the MoS2 phase while controlling its micromorphology and avoiding the strong interference from the alumina support to the phase, thus laying the foundation for accurate understanding of the origin of the active sites for HDN reactions. Then the catalytic activity of a series of MoS3-derived catalysts was thoroughly studied and comprehensive results are obtained after rationally deducing the “structure–function” relations: (i) two types of active sites exist in the HDN catalysts, one for the hydrogenation reaction which is related to both sulfur vacancies and brim sites and another for the C–N hydrogenolysis reaction which is connected with the –SH/S2− groups on the edge of the active phase; (ii) the edge composition directly influences the Ni-promoting effect and the “sulfur-deficient” edge structure is more beneficial for the promoter role of Ni. Due to the actual catalyst model first used, the resulting viewpoints exhibit valuable guiding significance for highly efficient HDN catalyst development.

Catalytic Performance and Synergetic Effect of Mo-V/Al2O3 in Residue Hy-drotreatment: Catalytic Performance and Synergetic Effect of Mo-V/Al2O3 in Residue Hy-drotreatment

Mo-V/Al 2 O 3 catalyst samples with different atom ratios of Mo/(Mo+V) were prepared by pore volume impregnation. The catalyst samples were characterized by Raman spectroscopy, H 2 temperature-programmed reduction, and high resolution transmission electron microscopy. The catalytic performance of Mo-V/Al 2 O 3 samples for model molecules (naphthalene) and for real feedstock (Kuwait atmosphere residue) was measured after sulfidation. Hydrogenation (HYD), hydrodemetallization (HDM), and hydrodesulfurization (HDS) were assessed. It can be concluded that Mo and V exhibited a synergetic effect in model molecules HYD and residue HDM reactions. Because the metals and sulfurs exist in different forms in residue and the V–S and V–Mo–S phases are more active for HDM than HDS, it is observed that the Mo-V/Al 2 O 3 catalyst exhibited higher HDM activity and lower HDS activity compared with the Ni-Mo/Al 2 O 3 catalyst.