Hydrodesulfurization (HDS)is a catalytic chemical process that widely used to remove sulfur from refined petroleum products such as gasoline or petrol, jet fuel, kerosene, diesel fuel and fuel oils. The purpose of this process is removing the sulfur. The hydrodesulfurization process takes place in a pseudo-three-phase fluidized-bed slurry bubble column reactor with liquid and gas growing upwards. This reactor presents a transient behavior for the catalytic effectiveness due to the obstruction of the catalyst pores,caused mainly by parallel reactions of hydrodemetalization acting on the...