Model Catalyst Performance and Efficiency during the Hydro-treatment of Heavy Oil Residuum

摘要

Fixed bed tubular plug flow reactor is used to investigate model catalysts performance during the hydrodesulphurization of Heavy Arabian Oil atmospheric residuum. The effects of temperature (300-380℃), pressure (30-80 atm) and particle size with characteristic lengths (Lp_(o) = 0.0059cm), Lp_(1) = 0.0327cm) on the rate of the Hydrodesulphurization reaction are investigated. Supported Co-Mo/ γ-AL_(2)O_(3) catalysts, CAT-1 with Co= 3wt.% and Mo= 10.6wt.% and 0.5wt.% MS 13X and CAT-2 with the same composition but without the addition of MS 13X loadings were prepared using the double impregnation method. All prepared catalysts were characterized for their porous structure and composition. A Kinetic equation was developed for pulverized CAT-1 particles, R_(HDS)= 9.9696*10~(10) exp (-17058/T) * P_(H2) *C_(S)~(2.2) / (1+0.00802 * P_(H2)). Effectiveness factors and effective diffusivity coefficients were estimated for both catalyst particle sizes. CAT-1 catalyst sample showing slightly higher activity lost approximately 20% of its initial activity after 450 hours of operation compared to 11% lost for CAT-2 sample. The presence of MS 13X in CAT-1 is accompanied with lighter HC products (C_(1)-C_(4) up to 210℃) giving rise to more hydrocracking orientations especially at high temperatures with higher API degrees of the treated products.