ESTIMATION OF SOLUBILITY OF SOLIDS IN SUPERCRITICAL CARBON DIOXIDE

Peng-Robinson equation of state（PR EOS）was chosen for modeling the thermodynamic be-havior of supercritical（SC）-CO2/Solid systems.The necessary critical constants and acentric factorof the solute were obtained by the Sigmund and Trebble（1992）method based on the molecular weightand boiling temperature,and the vapor pressure of the solute was calculated by its meltingtemperature and heat of fusion.This approach compared very favorably with the conventional corres-ponding state theory,but without using critical constants and vapor pressure of solutes.Four mixingrules were tested for the calculation of solid solubility in SC-CO2.van der Waals（vdW）mixing rulewith one parameter was considered to be most suitable for the estimation of solubility.A simplecorrelation was developed for the SC-CO2/solid binary interaction coefficient kij with the meltingtemperature of pure solutes.The solubilities of solids in SC-CO2 were estimated for eleven binarysystems at various temperatures,the total absolute

Peng - Robinson equation of state (PR EOS) was chosen for modeling the thermodynamic behavior of supercritical (SC) - CO2/Solid systems. The necessary critical constants and acentric factor of the solute were obtained by the Sigmund and Trebble(1992)method based on the molecular weight and boiling temperature, and the vapor pressure of the solute was calculated by its melting temperature and heat of fusion. This approach compared very favorably with the conventional corresponding state theory, but without using critical constants and vapor pressure of solutes. Four mixing rules were tested for the calculation of solid solubility in SC-CO2.van der Waals(vdW) mixing rule with one parameter was considered to be most suitable for the estimation of solubility. A simple correlation was developed for the SC-CO2/solid binary interaction coefficient kij with the melting temperature of pure solutes. The solubilities of solids in SC-CO2 were estimated for eleven binary systems at various temperatures, the total absolute average relative deviation (AARD)was 25.0%.