Synthesis, Characterization, and Hydrodesulfurization Activity of New Mesoporous Carbon Supported Transition Metal Sulfide Catalysts

The potential of sulfided Mo, Co, and CoMo catalysts supported on two different carbon mesostructures by KAIST-1 and 3 (CMK-1 and 3) for hydrodesulphurization (HDS) of thiophene at specific conditions was explored to investigate the effect of different pore sizes, surface functional groups, metal dispersion, and presulfidation temperature. Co/CMK catalysts were superior to Mo/CMK catalysts on the basis of same metal loading. The synergistic effect was found at Co/Mo ratio of 5/5. Sulfidation on carbon supported catalysts was favored at lower temperature of 300 °C, whereas higher temperature of 400 and 500 °C showed a more favorable effect on alumina supported catalysts. CMK-3 supported CoMo catalysts were superior to all other catalysts due to larger pore size and higher acidic surface functional groups. CMK-3 oxidized with nitric acid showed even better performance for CoMo (5:5) supported catalysts since the increased surface functional groups might induce better dispersion leading to higher HDS activity.