A comprehensive reactor modal for ethylene oxychlorination for the production of 1,2-dichloroethane in a fluidized-bed reactor is developed. The model is based on the two-phase theory of fluidization and allows for the change in volumetric gas flow rate in the dense phase due to the change in number of moles accompanying the reaction. The model predictions compared favorably with the industrial data obtained from the literature. The effect of different parameters on the behavior of the system is also investigated. It has been found that the bubble diameter, ethylene molar feed fraction, residence time, and height at minimum fluidization have significant effects on the reactor performance.