In this paper, a three-dimension Monte-Carlo simulation system of ZSM-5 zeolite crystal has been established. The deactivation process of ESMF zeolite crystal used as catalyst in benzene/ethylene alkylation reaction was simulated and the simulated results are in accord with accelerating deactivation experiment results. Deactivation process passes through three periods: stable high-level activity period, activity decline period and stable low-level activity period. Furthermore, effects of strong/weak acid si...