Effect of Alumina Support on the Formation of the Active Phase of Selective Hydrodesulfurization Catalysts Co-Mo/Al2O3

Abstract

Two different commercial alumina supports were used for the preparation of selective hydrodesulfurization (HDS) catalysts Co-Mo/Al 2 O 3 . The effect of support properties on the HDS activity and selectivity of the corresponding Co-Mo catalysts were studied by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, scanning transmission electron microscopy-energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The HDS activity and selectivity were measured using a continuous flow fixed-bed microreactor. The Al 2 O 3 support with higher crystallinity and fewer hydroxyl groups had a moderate metal-support interaction, which resulted in an increase of the average slab length and stacking number of MoS 2 . This gave more formation of the active CoMoS phase and an increase in HDS activity and selectivity. ：以两种商用 Al 2 O 3 为载体, 制备了汽油选择性加氢脱硫催化剂 Co-Mo/Al 2 O 3 , 并采用红外光谱、X 射线衍射、N 2 吸附-脱附、透射电镜、扫描透射-能谱和 X 射线光电子能谱等手段系统研究了载体物化性质对催化剂活性相形成的影响. 结果表明, 表面羟基数量少和结晶程度高的载体与活性金属间相互作用减弱, 促进了 Mo 物种的硫化还原, 使 MoS 2 片晶的尺寸和层数增加, 且其硫化态催化剂上 CoMoS 活性位更多, CoMoS/MoS 2 比更大, 因而显著提高了相应 Co-Mo 催化剂加氢脱硫活性和选择性. An Al 2 O 3 support with higher crystallinity and fewer hydroxyl groups has a moderate metal-support interaction that increased the slab length and stacking number of MoS 2 , which gave more formation of the active CoMoS phase and an increase in Hydrodesulfurization activity and selectivity.