Activity comparison of Ni-Mo/Al2O3 and Ni-Mo/TiO2 catalysts in hydroprocessing of middle petroleum distillates and their blend with rapeseed oil

Alumina supports are currently the most widely utilized supports for hydrotreating catalysts, which are used for production of low sulfur diesel fuels. However, the strong metal-support interactions, which may inhibit the desired kinetics of desulfurization, have driven the need to explore novel support systems. This research focuses on one such alternative support system - titania. This study compares the hydrodesulfurization (HDS), hydrodenitrogenation (HDN), and hydrogenation efficiency of sulfide Ni-Mo/Al2O3 and Ni-Mo/TiO2 catalysts in hydrotreating the middle petroleum distillates with and without 20 wt% of rapeseed oil. Hydrotreating experiments were executed in a fixed bed co-current tubular reactor using a commercial Ni-Mo/Al2O3 and an in house prepared Ni-Mo/TiO2 catalyst. The operating parameters were as follows: temperature in the range of 320-360 degrees C, pressure of 4 and 8 MPa, WHSV of ca 1.0 h(-1), and hydrogen to feedstock ratio of ca 240 m(3)/m(3). Ni-Mo/Al2O3 catalyst showed higher HDS, HDN and hydrogenation activity, mainly at 4 MPa pressure. The Ni-Mo/Al2O3 catalyst exhibited greater methanation activity, especially at 8 MPa pressure. The higher efficiency recorded with the Ni-Mo/Al2O3 catalyst may be attributed to this catalyses greater surface, formed by smaller mesopores size range.