Mixed solid phase model using equation of state based on hole-theory for solubility prediction of pharmaceutical compound in supercritical CO2

Abstract

A mixed solid phase model using an equation of state based on hole-theory is developed for solubility calculation in supercritical CO2 considering the dissolution of CO2 into solid phase at high-pressure condition. Parameters in the equation of state were obtained from the molecular information calculated by a quantum calculation based on conductor-like screening model (COSMO). Twenty-three species of pharmaceutical compounds are mentioned as the target for the correlation or prediction of solubility in supercritical CO2. The predicted results of the solubility in supercritical CO2 by the mixed solid phase model are compared with those by the conventional pure solid phase model. It is found that the results for the pharmaceutical compounds with S, N, F, Cl and I atoms using the mixed solid phase model give the calculation performance better than those of the pure solid phase model. The mixed solid phase model was also applied for calculation of the CO2 solubility in solid phase.