Hydrodesulfurization activity of CoMo catalysts supported on stabilized TiO₂

In this work we report the results of characterization and catalytic behavior of different CoMo-based catalysts supported on titania modified with lanthanum and cerium. Co and Mo contents of catalysts were between 25 and 100% of the corresponding amount of metals commonly found in commercial catalysts (Co + Mo = 12.85 wt %). For all catalyst a constant Co/Mo weight ratio was kept at about 0.22. Catalytic activities were evaluated using dibenzothiophene hydrodesulfurization as model reaction. On the bases of specific surface area results and XRD measurements analyses after hydrothermal deactivation, it was found that suitable contents of La and Ce in the support are 2 and 10 wt %, respectively. DBT conversion of Ti-La catalysts was slightly higher than Ti-Ce catalysts, and both showed maximum values of conversion at 50 and 75% of the amount of metals in commercial catalysts.