Thermochimica Acta, Vol.569, 48-54, 2013
Solubility of megestrol acetate and levonorgestrel in supercritical carbon dioxide
The solubilities of two estrogenic drugs so called levonorgestrel and megestrol acetate were measured in supercritical carbon dioxide (SC-CO2) medium. The temperatures and pressures of experiments were in the range of (308-338)K and (12.2-35.5) MPa, respectively. The solubilities mole fraction ranged from 4.30 x 10(-6) to 8.70 x 10(-4). Under miscellaneous pressures and temperatures conditions, four density based models (Chrastil, modified Chrastil, Bartle and Mendez-Santiago and Teja (M-T)) were applied in order to predict the mentioned drugs solubilities in SC-CO2 medium. Comparing three above models, it was showed that the best results of the solubilities data are M-T model with an overall average absolute relative deviation (AARD) of 0.062 for levonorgestrel and the modified Chrastil with an overall AARD of 0.097 for megestrol acetate. The heat of drug-CO2 solvation and that of drug vaporization was approximated in the range of (-10.37 to -13.76) and (64.6-67.9)kj/mol. (C) 2013 Elsevier B.V. All rights reserved.
Keywords:Density based model;Solubility;Supercritical carbon dioxide;Levonorgestrel;Megestrol acetate;Semiempirical models