Several Mo catalysts supported on zeolite USY, HZSM-5 and MCM-41 were prepared using incipient wetness impregnation method in order to investigate their thiophene HDS(hydrodesulfurization) characteristics. All catalysts were activated under four different conditions(sulfidation, nitridation, nitridation followed by sulfidation and nitridation followed by reduction, respectively). The characteristics and pretreatment of effects of Mo containing zeolite catalyst were investigated by thiophene HDS, XRD, $NH_3$ TPD, XPS, BET, pore size distribution, TEM and TGA.
The HDS activities of zeolite supported Mo catalysts were equivalent to those of alumina supported Mo catalysts. MCM-41 supported Mo catalysts showed the highest HDS catalytic activities among those of USY and HZSM-5 supported Mo catalysts due to its higher surface area, larger pore channel and mild acidity. However, zeolite supported Mo catalysts were deactivated rapidly owing to coke developed by acidity of zeolites, which was confirmed by $NH_3$ TPD and TGA.
By the elemental analysis, it could be seemed that considerable amount of Mo was converted to $Mo_2N$ or $MoO_xN_{x-1}$. And Mo nitride catalyst without sulfidation or reduction showed lower HDS activity than Mo nitride and Mo oxide catalyst followed by sulfidation.
