This work presents a 3D VOF two-phase model to investigate the hydrodynamics, chemical reaction heat, and multicomponent mass transfer of 1, 1 diethoxy butane (DEB) production in a reactive distillation column. Two types of internal, katapak SP-11 and 12, were studied. Penetration theory of Higbie was applied to the mass transfer coefficient of liquid. Mass fraction of each component in the gas phase at the outlet of stages was shown and compared to the experimental data. Results showed that the butanal of the liquid phase enters to the gas phase with the rising of gas along the column, which some amounts of ethanol, water, and DEB in the gas phase is absorbed in the liquid. Moreover, the mass transfer in open channels is more than closed channels. The comparison shows that they are in satisfactory agreement, with relative errors lower than 10%. Furthermore, according to CFD results, the conversions are decreased due to the generation of products. As the reaction is exothermic, the rate of rising in temperature decreases as the conversion rate decreases. The mean relative errors for prediction of mole fraction and temperature were 10% and 3%, respectively.