A steady bubble gas liquid mass-transfer model for studying wet limestone scrubbing is established on the basis of the film theory and the principle of mass conservation. The characteristic, size, solid loading, and bubble size of the fine particles have a great influence on gas liquid mass transfer. The present work is to explain how these factors influence the reaction between Na2SO3 and O-2 and find the best reaction conditions through experiment. From the modeling study, the sulfite oxidation reaction rate is affected by the concentration of sulfite, bubble size, and mass diffusion coefficient. The reaction order with respect to the bubble radius is 0 during the kinetic-controlled process and -1 during the diffusion-controlled process. The oxidation rate was experimentally studied by contacting pure oxygen with sodium sulfite solution in the single-bubble system. Theoretical results show good agreement with the experimental data. It has been found that the fine particle and bubble size rather than the mass-transfer coefficient play a more significant role in controlling the overall rate of mass transfer in the system.