Effects of gallium addition to mesoporous alumina by impregnation on dibenzothiophene hydrodesulfurization performances of the corresponding NiMo supported catalysts

摘要

The effects of gallium (Ga) modification on mesoporous Al2O3 (MA) were studied, focusing on the morphology changes of the active phases and the application as catalyst support for catalytic performances for dibenzothiophene (DBT) hydrodesulfurization (HDS). MA samples with wide mesopore size distribution (MA-W), double mesopore size distribution (MA-D) and single mesopore size distribution (MA-S) were synthesized from the boehmite sol-gel via a hydrothermal synthesis method. The synthesized MA-S sample was modified with Ga2O3, and the corresponding sulfide NiMo supported catalysts were prepared. The as-synthesized samples were characterized by XRD, N-2 physisorption, NH3-TPD, H-2-TPR, HRTEM and XPS. Superior catalytic performance was observed over the NiMo/MA-S-2Ga catalyst due to the moderate interaction between the active metals and the supports; the superior morphology for Ni promoted MoS2 crystals, the highest sulfidation degree, the largest proportion of the NiMoS phase and the enhanced hydrogenation activity caused by the introduction of Ga species.