Solubility of large crown ethers in supercritical carbon dioxide

The equilibrium solubilities of dibenzo-24-crown-8 (DB24C8), dibenzo-27-cro wn-9 (DB27C9), and dibenzo-30-crown-10 (DB30C10) have been measured in supe rcritical carbon dioxide. The measurements were performed in the pressure r ange from 120 to 440 atm at temperatures 35. 45, 55 and 65 degreesC for DB2 4C8 and in the pressure range from 120 to 480 atm at temperatures 35, 45, 5 5, 65 and 75 degreesC for DB27C9 and DB30C10. The solubility of the crown e thers in supercritical carbon dioxide was found to vary in the order DB24C8 > DB27C9 much greater than DB30C10. The measured solubilities were correla ted using a semi-empirical model. The calculated results show satisfactory agreement with the experimental data. (C) 2001 Elsevier Science B.V. All ri ghts reserved.