Catalyst Ni-Mo/Al2O3 promoted with infrared heating calcination for hydrodesulfurization of shale oil

Abstract

Ni-Mo/Al2O3 catalyst calcinated using infrared radiation heating was applied for the first time to hydrodesulfurization (HDS) of shale oil in a fixed bed reactor. Its catalytic performance was measured under varied operating conditions and compared to that obtained by using a catalyst with the same Ni-Mo composition but calcinated in a conventional electric furnace. The operation parameters of HDS were varied among temperature (320–400 °C), pressure (1.0–4.0 Mpa), H2/oil (v/v) (200:1–600:1) and LHSV (1–4 h−1). Under all tested conditions, the catalyst using the infrared heating method always yielded a product oil having the lower sulfur content than the catalyst heated by the conventional furnace did. At the optimal condition of T = 380 °C, P = 4 MPa, H2/oil (v/v) = 600:1 and LHSV = 4 h−1, the infrared-heating catalyst enabled the oil to decrease its sulfur content to 2600 ppm, which thus met the national Marine fuel oil standard (S < 0.5 wt%, GB1711-2015, China). Characterization of the fresh, sulfided and spent catalysts shown that the catalyst calcinated with the infrared heating had the higher BET surface area, smaller and narrower size distribution of metal particles, higher binding energy between Mo and S, and more oxygen-deficient sites in comparison with the catalyst calcined using conventional electric heating.