Effect of ordered mesoporous Zr SBA-15 support on catalytic functionalities of hydrotreating catalysts 2. Variation of molybdenum and promoter loadings

Abstract

ZrSBA-15 support with Si/Zr=20 containing majority of Zr in framework positions is synthesized by direct addition of Zr to the synthetic mixture. Various catalysts containing 2–12 molybdenum loading were prepared by incipient wetness impregnation. Using 8wt% Mo catalysts Co and Ni promoted catalysts were prepared with 1–5wt% promoter loading. All the Mo, CoMo, NiMo catalysts were characterized by N2 adsorption–desorption, low angle and wide angle XRD, temperature programmed reduction (TPR) and oxygen chemisorption on sulfide catalysts. The catalytic activities for thiophene HDS, cyclohexene HYD were evaluated on sulfide catalysts at 400°C. The oxygen uptakes and catalytic activities for HDS and HYD passed through a maximum at 8wt% loading. The H2/Mo ratios obtained as a function of Mo loading also passed through a maximum at the same temperature. The promoted catalyst showed maximum activity at 3wt% loading for both the functionalities. These results will be discussed in the light of characterization results in terms of reducibility, dispersion and anion vacancy variation with Mo and promoter loading.