Determination of vapor pressure and solubility correlation of phenolic compounds in supercritical CO2

New vapor pressure data for phenolic compounds (caffeic acid, ferulic acid, and p- and o-coumaric acids) were experimentally obtained and compared to values predicted by a group contribution method. A gas–liquid chromatography method was used to experimentally determine the vapor pressure since this method is reliable, reproducible and rapid. These vapor pressure data were then used to predict second cross virial coefficients of phenolic compounds in supercritical carbon dioxide (SC CO2) using a method based on the residual chemical potential in terms of the virial coefficients and fluctuation theory. The solubility results obtained by this method were compared to those from two other correlations based on the regular solution theory and Chrastil equation. Good agreement was obtained with the correlations when compared to the experimental literature data on the solubility of phenolic compounds in SC CO2.