Characterization and utilization of hydrotreated products from the Whiterocks (Utah) tar sand bitumen-derived liquid

The bitumen-derived liquid produced in a fluidized-bed reactor from the Whiterocks tar sand was hydrotreated over a sulphided Ni-Mo/Al₂O₃ hydrodenitrogenation catalyst in a fixed-bed reactor. The process variables studied were temperature (617–680 K), pressure (11.0–17.1 MPa) and liquid hourly space velocity (0.18–0.77 h⁻¹). The feed and the hydrotreated liquid products were analysed by gas chromatography-mass spectrometry analyses. The compounds identified in the bitumen included isoprenoids; bicyclic, tricyclic, and tetracyclic terpenoids; steranes; hopanes; and perhydro-β-carotenes. Normal and branched alkanes and alkenes and partially dehydrogenated hydroaromatics were identified in the bitumen-derived liquid. Comparison of the compounds identified in the bitumen and the bitumen-derived liquid indicated that the dealkylation of long alkyl side chains 0to form - and isoolefins and the cleavage of alkyl chains linking aromatic and hydroaromatic clusters were the dominant pyrolysis reactions. Monoaromatic hydrocarbons were the predominant aromatic species in the hydrotreated product. The properties of the jet fuel fractions from the hydrotreated products met most of the jet fuel specifications. The cetane indices indicated that these fractions would be suitable for use as diesel fuels.