Synthesis and hydrodesulfurization properties of NiW catalyst supported on high-aluminum-content, highly ordered, and hydrothermally stable Al-SBA-15

Al-SBA-15 was prepared by adjusting the pH value during high-temperature hydrothermal treatment. Appropriate metal–support interaction combined with suitable acidity endowed the NiW/Al-SBA-15 catalyst with excellent hydrodesulfurization activity. Highly ordered mesoporous Al-SBA-15 with high aluminum content and high hydrothermal stability has been synthesized by a new pH-adjusting and high-temperature hydrothermal treatment approach. Thus-prepared samples were characterized by X-ray fluorescence spectroscopy, X-ray powder diffraction, 27Al nuclear magnetic resonance spectroscopy, N2 adsorption–desorption, temperature-programmed desorption of ammonia, Fourier transformed infrared spectroscopy with pyridine adsorption, temperature-programmed reduction with hydrogen, and high-resolution transmission electron microscopy. The results showed that Al-SBA-15 had high aluminum loading (with its molar Si/Al ratio of 5.1, similar to that of the initial gel mixture) and homogenously distributed Al species in the walls. Moreover, the product showed extremely high hydrothermal stability (with only a 15.2% decrease in surface area after steaming at 800°C for 5h) and moderate acidity. An Al-SBA-15-supported NiW hydrodesulfurization catalyst was prepared and evaluated using dibenzothiophene hydrodesulfurization. Compared with γ-Al2O3- and SBA-15-supported catalysts, the Al-SBA-15-supported NiW catalyst showed outstanding hydrodesulfurization activity.