The solubility of NaCN and Na 2 CO 3 in the water-ethanol mixture was determined through experiments. Also the polynomial fit was used to lead to the relationship between the solubility of NaCN/Na 2 CO 3 and the solvent composition. In the meantime, the solvent molecular-electrolyte pair interaction parameters of electrolyte NRTL (eNRTL) model were estimated by using the data regression function of Aspen Plus software from solubility data of NaCN and Na 2 CO 3 in water-ethanol mixed solvent. The process simulation for separation and purification of NaCN and Na 2 CO 3 in water-ethanol mixed solvent was carried out by using Aspen Plus software. During the simulation, electrolyte equilibrium system in water-ethanol mixed solvent was observed by using eNRTL model property method, and the influence of several factors on the separation efficiency of NaCN was examined.