Abstract: The kinetics of dechlorination of Ca-based sorbents was explored in this paper, in order to confirm the factors that control the reaction rate in the combustion.A shrinking core model of nonporous CaO-HCl was built.From this model, the effects of such factors as reaction temperature, reaction time, concentration of HCl, particle size of CaO on dechlorination characteristics were studied.The results showed that the model fitted experimental results, so the model could reflect the course of dechlorination well.