Sodium carbonate was used as a sorbent to capture CO2 from a gaseous stream of carbon dioxide, nitrogen, and moisture. The breakthrough data of CO2 were measured in a fixed bed to observe the reaction kinetics of CO2-carbonate reaction. Several models such as the shrinking-core model, the homogeneous model, and the deactivation model in the non-catalytic heterogeneous reaction systems were used to explain the kinetics of reaction among CO2, Na2CO3, and moisture using analysis of the experimental breakthrough data. Good agreement of the deactivation model was obtained with the experimental breakthrough data. The sorption rate constant and the deactivation rate constant were evaluated by analysis of the experimental breakthrough data using a nonlinear least squares technique and described as Arrhenius form.