Catalytic Desulfurization of Gasoline via Dehydrosulfidation

This study presents a potentially attractive route for the desulfurization of gasoline via catalytic dehydrosulfidation, removal of hydrogen sulfide from sulfur-containing molecules. The proposed study involves thermodynamic calculations and experimentation in a fluidized riser simulator at the Chemical Reaction Engineering Centre (CREC) at the University of Western Ontario. A ZSM-5 catalyst was used because of its demonstrated performance for the dehydration of methanol, a parent reaction with an expected similar reaction network. The catalyst was characterized using several techniques, including (a) BET (surface area), (b) ammonia temperatureprogrammed desorption (concentration of acid sites), and (c) SEM-EDX (sodium content) at various stages of catalyst preparation. The catalytic dehydrodesulfidation reaction was studied using a model compound (ethyl mercaptan, EM) in n-octane (n-C8) to represent sulfur-contaminated gasoline. The experimental data obtained were successfully fitted using a kinetic model representing the rate of disappearance of the sulfur-containing species.