This paper studies the kinetics of the reaction between NaClO₃, FeSO₄, and NaHSO₃, which can potentially be used as an alternative to the conventional lime-limestone process for flue gas desulfurization. The key for the establishment of a kinetic model of the reaction is to find a way to determine concentrations of reactants or products during the reaction. The generation rate of Cl^- during the reaction was monitored using a Dionex Series 4000i ion chromatograph. Based on the changes of Cl^- concentrations at the designed initial reaction conditions, reaction orders for each reactant were derived. The reaction orders were determined to be 1.1 for NaClO₃, 1.1 for FeSO₄, and 1.4 for NaHSO₃. The global rate coefficients of the reaction at temperatures ranging from 40 to 80 °C were determined. Furthermore, the preexponential factor and the activation energy in the empirical Arrhenius form of the reaction were derived from the relationship between temperature and its corresponding observed global rate coefficient.