Molybdenum anchored on NH2-modified spherical SiO2: A highly efficient and stable catalyst for oxidative desulfurization of fuel oil

A catalyst (Mo-NH2-SiO2) has been synthesized via anchoring of Mo species onto the surface of 3-aminopropyltriethoxysilane-modified SiO2 (NH2-SiO2) and applied in the catalytic oxidative desulfurization of fuel oil. Structure and properties of the catalyst were investigated using X-ray diffraction, transmission electron microscopy, X-ray photoelectron and Fourier transform infrared spectroscopies and nitrogen adsorption-desorption measurements. The hydrophilic/hydrophobic characters of the catalyst were also studied. The results demonstrated that the synthesized catalyst possessed highly dispersed Mo species with an electron-rich state and a strong hydrophobic character, which contributed significantly to increases of both catalytic activity and stability. Dibenzothiophene in model oil could be removed completely, and the removal of sulfur from diesel oil (21 500 ppmw) also reached 80.4% at 60 degrees C in 60min. Furthermore, the catalyst was recycled in ten reaction runs without obvious influence on activity. This work provides a novel way for preparing high-activity and stable catalysts for oxidative desulfurization of fuel oil, which will have potential industrial applications.