New Experimental Data and Modeling of the Solubility of Compounds in Supercritical Carbon Dioxide

The solid solubility of o -nitrobenzoic acid in supercritical carbon dioxide (SCCO 2 ) was measured using a dynamic-flow technique at 308, 318, and 328 K and in the pressure range of 10.0–21.0 MPa. The experimental solubility data of the solute in SCCO 2 were correlated by six different theoretical semiempirical models [the Chrastil, Kumar and Johnston, Sung and Shim (SS), Méndez-Santiago and Teja, Bartle–Clifford–Jafar–Shilstone, and Jouyban–Chan–Foster models] with the average absolute relative deviation from 4.30% to 6.61%. The correlated results indicate that the SS model provides the best fit. Solubility data from 54 different compounds of different functional groups (including carboxyl, amino, chain alkyl, heterocycle, azo, diglycolic, and anthraquinone) were collected from the literature to compare and evaluate these models. The division criteria of temperature, pressure, mole fraction solubility of the solutes, and number of experimental data points were established. The predictive capability and applicability of these models for different types of solutes and at different conditions are demonstrated in this paper.