A new simple static method for the determination of solubilities of condensed compounds in supercritical fluids

摘要

A simple static method based on gravimetric measurements has been adopted to measure the solubility of benzenecarboxylic acid, 2-hydroxy-benzenecarboxylic acid, 4-hydroxy-benzenecarboxylic acid and 1,8-dihydroxyan-thraquinone along several isotherms in the temperature range 318-357 K and the pressure interval 7-23 MPa. Solubility data have been correlated with the Zieger-Eckert approach, using the Fedor atomic and group contribution method to estimate the solubility parameter and the molar volume of the solutes. A good agreement was obtained between data reported in the literature and those determined using the proposed method which allows one to measure solubility mole fraction as low as 10~(-5). Provided that a suitable analytical technique is adopted the method can be extended also to multicomponent systems.