Description of Solubility in Supercritical Carbon Dioxide as a Method of Determining the Saturated Vapor Pressure of Dissolved Substances

摘要

The influence of the method of determining the vapor pressure of various substances on the accuracy of the description of their solubilities in supercritical carbon dioxide is studied. It is shown that in most cases the computational methods of Clapeyron, Lee-Kesler, Riedel, Frost-Kolkuorf-Todos, and Riedel- Plank-Miller do not allow experimental data to be described with acceptable accuracy (up to 10-12%). The accuracy of the description of solubility is significantly increased by using the saturated vapor pressure as the second fitting parameter in addition to the coefficient of binary interaction. It is suggested to use the described approach to indirectly determine the saturated vapor pressure of substances through the description of their solubilities. It is shown that the results obtained using this approach are much better consistent with the experimental data than those obtained by the above mentioned calculation methods.