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Herein, a series of mesoporous NiMo/LaAlOx with various La contents were constructed through a solvent evaporation‐induced self‐assembly protocol, and their catalytic activities were investigated for hydrodesulfurization (HDS) of 4,6‐DMDBT. It has been confirmed that the incorporation of La influences the electronic structure and morphology of NiMoS active phase. The lower amount of La (x ≤ 1.0 wt.%) could facilitate the formation of "Type II" NiMoS phase by weakening the interaction of Mo‐O‐Al leakage and promoting the sulfidation of both Mo and Ni species as well as increasing the ratio of "Type II" NiMoS phase, thereafter boosting the HDS performances. Further increasing La incorporation, however, leads to the generation of inactive NiSx phase and decrease of NiMoS active phase proportion, the HDS activities of corresponding catalysts were suppressed. NiMo/LaAlOx‐1.0 exhibits the highest activity for 4,6‐DMDBT HDS because of its moderate metal‐support interaction, optimal morphology and the largest proportion of "Type II" NiMoS active phase. [ABSTRACT FROM AUTHOR]

• ● A novel Pt-Ni 2 P/Al 2 O 3 catalyst with 0.50 wt% Pt loading was prepared by an incipient wetness impregnation method; • ● The introduction of Pt promoted the hydrogen atoms produced by the dissociated adsorbed hydrogen molecules; • ● The introduction of Pt increased the number of stronger Lewis acid and Brønsted acid sites; • ● The ultradeep HDS performance of Pt-Ni 2 P/Al 2 O 3 catalyst for 4,6-dimethyldibenzothiophene (4,6-DMDBT) was boosted. The catalytic performances of conventional Ni(Co)Mo(W)/Al 2 O 3 catalysts for hydrodesulfurization (HDS) of fuel are far from meeting the near zero emission standards. Therefore, the development of more efficient ultradeep HDS catalyst is highly desirable. Herein, a novel Pt-Ni 2 P/Al 2 O 3 catalyst with 0.5 wt% Pt loading was prepared, and its catalytic performance for HDS of 4,6-dimethyldibenzothiophene (4,6-DMDBT) was investigated. The introduction of Pt considerably promoted the reducibility and hydrogen atoms produced by the dissociated adsorbed hydrogen molecules on the Pt surface overflowing to the Ni 2 P because of the lower electronegativity of Pt than that of Ni, thereby increasing the number of stronger Lewis and Brønsted acid sites, and thereafter greatly boosting the direct desulfurization and isomerization pathways. As a result, Pt-Ni 2 P/Al 2 O 3 catalyst achieved the ultradeep HDS of 4,6-DMDBT, with 100% conversion at 340 °C, remarkably higher than that of Ni 2 P/Al 2 O 3 (49.8%) and NiMo/Al 2 O 3 (62.0%) counterparts. [ABSTRACT FROM AUTHOR]

• A variety of Ni 2 P/GaAlO x catalysts with various Ga doping were prepared. • The doping of Ga influences the surface acidity, MSI, morphology, and electronic structure of Ni 2 P. • Ni 2 P/GaAlO x -0.50 exhibits optimal HDS performance with 70.1% 4,6-DMDBT conversion. • Ni 2 P/GaAlO x -0.50 shows higher k HDS and TOF than that of the other counterparts. Modifying the structure of active phase is an effective protocol to improve the catalytic activity of hydrodesulfurization (HDS) catalyst. Here, a variety of mesoporous GaAlO x supports with various Ga doping amount were synthesized by a facile hydrothermal strategy. The corresponding Ni 2 P supported catalysts were fabricated via a conventional impregnation and temperature-programmed reduction method, and their catalytic performances for 4,6-DMDBT HDS were examined. The experimental analyses show that the introduction of Ga substantially influences the geometric and electrical structure of Ni 2 P active phase on Ni 2 P/GaAlO x catalysts. The metal-support interaction is effectively abated with the elevation of Ga doping amount, thereby increasing the d-electron density of Ni species and boosting the pre-hydrogenation (HYD) route, thereupon enhancing the HDS performances of corresponding Ni 2 P/GaAlO x catalysts. Therein, Ni 2 P/GaAlO x -0.50 exhibits the highest activity with 70.1% 4,6-DMDBT conversion because of the optimal morphology and percentage of active phase, as well as distinguished redox and acid property. Further increasing the Ga loading, however, inhibits the HDS activity of Ni 2 P/GaAlO x -1.0 catalyst due to the decrease in the fraction and dispersion of active phases. Therefore, this work may shine light on the understanding of structure–activity of HDS catalyst and thereafter the preparation of HDS catalysts with high efficiency in future. [ABSTRACT FROM AUTHOR]

Herein, a set of NiMo/Al 2 O 3 catalysts with distinct coordination state of surface alumina were design and prepared by a facile calcination strategy. Various characterization methods were employed to analyze the structural properties of NiMo/Al 2 O 3 catalysts, and the catalytic performances of corresponding catalysts were tested for hydrodesulfurization (HDS) of 4,6-dimethyldibenzothiophene (4,6-DMDBT). The results indicate that the synthesized samples show uniform specific surface area (130 m2·g−1) and pore size (3.5 nm), but varying penta-coordinated aluminum content, which significantly influences the NiMo/Al 2 O 3 catalysts' surface acidity. Therein, NiMo/Al 2 O 3 -600 prepared by calcination at 600 °C exhibits the highest ratio of penta-coordinated aluminum species, which endows more abundant Brønsted acid than that of tetra- and hexa-coordinated aluminum counterparts, thereby substantially promoting the isomerization and direct desulfurization pathways of 4,6-DMDBT HDS, and thereafter considerably boosting the HDS performance of NiMo/Al 2 O 3 -600 with 94.5 % 4,6-DMDBT conversion, which is notably higher than that of NiMo/Al 2 O 3 -500 (74.4 %) and NiMo/Al 2 O 3 -700 (62.7 %). [Display omitted] • A series of NiMo/Al 2 O 3 catalysts with distinct coordination state of surface alumina were prepared; • These NiMo/Al 2 O 3 catalysts show approximately the same specific surface area and pore size"; • NiMo/Al 2 O 3 -600 exhibits more penta-coordinated aluminum species and Brønsted acid sites; • The HDS performance of NiMo/Al 2 O 3 -600 was boosted due to the promoted ISO and DDS pathways. [ABSTRACT FROM AUTHOR]