Optimal Synthesis of Hierarchical Porous Composite ZSM-5/SBA-16 for Ultradeep Hydrodesulfurization of Dibenzothiophene and 4,6-Dimethyldibenzothiophene. Part 2: The Influence of Aging Temperature on the Properties of NiMo Catalysts

Abstract

ZSM-5/SBA-16 (ZS) supports were prepared using the two-step hydrothermal crystallization method. The effect of the aging temperature on the structural properties of the series ZS supports was studied. The prepared samples were analyzed by X-ray diffraction, scanning electron microscopy, N2 physisorption, 27Al magic angle spinning nuclear magnetic resonance, H2 temperature-programmed reduction, Raman, X-ray photoelectron spectroscopy, pyridine–Fourier transform infrared spectroscopy, and high-resolution transmission electron microscopy. The hydrodesulfurization performances of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) were examined at T = 340 °C and PH2 = 4 MPa. The NiMo/ZS-45 catalyst synthesized at the aging temperature of 45 °C exhibited the best catalytic activities of DBT and 4,6-DMDBT, which were attributed to its regular shape, well-organized pore structure, high sulfidation degree, and a compromise between the acidity and metal–support interaction (MSI, Mo–O–Si). Moreover, the possible DBT and 4,6-DMDBT HDS reaction networks over NiMo/ZS-45 were proposed.