Solubilities of some hydroxyxanthone derivatives in supercritical carbon dioxide

The equilibrium solubilities of four hydroxyxanthone derivatives have been measured in supercritical. carbon dioxide using a. simple and reliable stat ic method. The measurements were performed in the pressure range 74.0-354.6 bar at the temperatures 32, 45, 55, 65, and 75 degrees C. The order of sol ubility observed for the compounds used was discussed in terms of their pos sible intra- and intermolecular H-bonds and polarities. The measured solubi lities were correlated using a semiempirical model. The calculated results show satisfactory agreement with the experimental data.