AN EMPIRICAL-METHOD TO EVALUATE THE SOLUBILITY OF SEVERAL GASES IN POLAR AND NONPOLAR-SOLVENTS

A predictive method, based on the application of the NRTL equation, is proposed to evaluate the solubility of in polar and non-polar solvent s. The method relies on two main hypotheses: (i) the symmetrical conve ntion can be assumed for the activity coefficients of supercritical co mponents also according to a procedure previously proposed by the auth or; (ii) the NRTL binary constants can be evaluated through simple gen eralized correlations which link these parameters to the pure componen ts properties expressed by the Hildebrand solubility parameter and the molar volume. The solubilities of ten gases (H-2, O-2, N-2, CH4, C2H4 , C2H6, C3H8, CO, CO2, H2S) in both non-polar and polar solvents are e xamined. Usually, each gas requires two ''ad hoc'' procedures for pola r and non-polar solvents, respectively. The proposed method is applied to more than 100 literature systems which cover a wide range of exper imental conditions. The reliability of the predictions is expressed by the percent deviations of calculated pressures and vapor compositions from the experimental data. A comparison is also made with two litera ture methods. (C) 1997 Elsevier Science B.V.