Abstract: Ni-Mo oxide powders were prepared by sol-gel method using carbon black as pore-enlarging agent. Ni-Mo composite oxide bulk catalysts were prepared by using a mixture of diatomaceous earth and alumina gel as binder. The catalysts were characterized by XRD, BET, Py-IR, NH3-TPD. The effect of diatomaceous earth addition on hydrothermal/mechanical stability of bulk hydrodeoxygenation catalyst was examined. The hydrodeoxygenation performance was evaluated using n-octane solution containing 20% jatropha oil as the raw material. The results showed that the addition of diatomaceous earth during the preparation of the catalyst did not significantly affect the crystal phase of the catalyst, but significantly increased the pore size of the catalyst; the added diatomaceous earth covered part of the Al3+ exposed on the surface of the catalyst and in the pores, which can effectively inhibits the collapse of the pore structure of the catalyst and the aggregation of the metal particles caused by the hydration reaction of the Al2O3. As a result, the hydrothermal/ mechanical stability of the catalyst are significantly improved.

Key words: diatomaceous, Ni-Mo composite oxide catalyst, Hydrodeoxygenation, hydrothermal/mechanical stability