A new method for estimating solubility of fatty acids, esters, and triglycerides in supercritical carbon dioxide

Abstract  A method to predict solubility of fat compounds (fatty acids, fatty acid esters, and triglycerides) in supercritical CO2 in the absence of experimental data is presented. The method is based on the idea of group contribution, so only knowledge about the chemical structure of the substance is needed to predict its solubility in CO2. Chrastil's equation was used to correlate the solubilities of fatty acids, fatty acid esters, and triglycerides in CO2. The three parameters determined from fitting of the data were calculated. A nonlinear fit routine was used to determine the chemical group contributions to the three parameters. Analysis of the results shows that it is possible to correlate the parameters of Chrastil's equation to molecular groups. The average deviation from the experimental data was 8%.