Catalytic Carbonization of Vacuum Residual Oil from Orinoco Tar Sand

Orinoco vacuum residue of a heavily contaminated oil was carbonized in the presence of aluminum chloride under variable heating rates to reveal its influence on the quality and quantity of gas, oil, and coke products. The catalyst accelerated the desulfurization and denitrogenation reactions to produce the coke and oil of higher purity. The catalyst could modify the coking properties of the residual oil to produce flow texture. The coke and gas yields were in general increased by the catalyst; however, the higher heating rate (1200 °C/h) could produce a considerable amount of clean oil. Addition of hydrogen donating additive such as 9,10-dihydroanthracene promoted the desulfurization and mesophase development, consequently reducing the catalyst amount required for the sufficient desulfurization and flow texture. Naphthenic intermediate which, being itself fusible, can dissolve the heavier products by hydrogen transfer may play an important role in these processes. Hydrogen donating additive may play the same role.