The surface properties of aluminated meso-macroporous silica and its catalytic performance as hydrodesulfurization catalyst support

摘要

Aluminated mesoporous silica was prepared by multiple post-grafting of alumina onto uniform mesoporousSiO2,which was assembled from monodisperse SiO2 microspheres.Hydrodesulfurization (HDS) catalyst was prepared by loading Ni and Mo active components onto the aluminated uniform mesoporous SiO2,and its HDS catalytic performance was evaluated using hydrodesulfurization of dibenzothiophene as the probe reaction at 300 ℃ and 6.0 MPa in a tubular reactor.The samples were characterized by N2 physisorption,scanning electronic microscopy,Fourier transform infrared spectrum,X-ray diffraction (XRD),temperature-programmed desorption of ammonia (NH3-TPD),27A1 nuclear magnetic resonance (27A1-NMR) and high-resolution transmission electron microscopy (HRTEM).The results showed that the Si-OH group content of SiO2 was mainly dependent on the pretreatment conditions and had significant influence on the activity of the NiMo catalyst.The surface properties of the aluminated SiO2 varied with the A12O3-grafting cycles.Generally after four cycles of grafting,the aluminated SiO2 behaved like amorphous alumina.In addition,plotting of activity of NiMo catalysts supported on aluminated mesomacroporous silica materials against the A12O3-grafting cycle yields a volcano curve.