(509ar) Synthesis and Characterization of Ni-Mo-W Sulfide Catalysts Supported on Aluminum-Titanium Mixed Oxides

This work reports the synthesis and characterization of trimetallic Ni-W-Mo sulfide catalysts supported on titanium-aluminum mixed oxides (MO). The MO was synthesized by the Sol-Gel method with different percentages of TiO2 in Al2O3 (0, 10, 20, 30, 40, 50 and 100 respectively). The supports were calcined at 773 K under air flow during 4 hours, and then pilled and sized to 25-40 mesh. Molybdenum and Tungsten thiosalts were synthesized by reacting ammonium heptamolibdate or metatunsgtate in solution under a H2S/H2 flow. The Mo and W thiosalts and Ni(NO3)6H2O were first dissolved, and then supported on the MO by co-impregnation at an atomic ratio Ni:W:Mo of 2:1:1 respectively and 18wt% of W+Mo. Sulfidation of materials was performed under a flow of H2S/H2 (15%v/v) during 4 hours, and the catalysts were then characterized by specific surface area measurements (BET), distribution and pore size by the BJH method, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results showed good dispersion of W, Mo and Ni, high specific surface areas, characteristic of the MO, and poorly crystalline structures. Furthermore, the TEM images showed that nickel sulfide structures are formed on the surface when the percentage of TiO2 in the support is higher than 20 %, which were not detected by XRD.