HYDROTREATMENT PROCESS KINETICS FOR BITUMEN AND BITUMEN-DERIVED LIQUIDS

Hydrodenitrogenation, hydrodesulfurization and resid conversion data for the Whiterocks bitumen and bitumen-derived liquid were analysed using a modified power rate law model. The data were obtained with a fixed-bed reactor in the upflow mode. A space velocity (WHSV(alpha)) term was included to account for deviations from plug flow behaviour. The upflow mode was preferred to the trickle-bed mode to ensure complete wetting of the catalyst and nearly isothermal operation. The apparent kinetic parameters were obtained by combined non-linear regression and ODE solver techniques for the analysis of laboratory data. A simple nth-order power rate law expression for hydrodenitrogenation and hydrodesulfurization was examined. The higher than first-order kinetics for hydrodenitrogenation and hydrodesulfurization of the bitumen and bitumen-derived liquids were explained by invoking two parallel first-order reactions for the facile and refractory fractions or lumps. Parallel and consecutive reaction schemes were used to examine the extent of conversion of the resid fraction to middle distillate, gas oil and naphtha. The apparent kinetic parameters were also determined.