Correlation of solubilities and entrainer effects for fatty acids and higher alcohols in supercritical carbon dioxide using SRK equation of state with association model

Solubilities of fatty acids (myristic acid, palmitic acid and stearic acid) and higher alcohols (cetyl alcohol, stearyl alcohol and arachidyl alcohol) in supercritical CO2, and the entrainer effect (ethanol or octane) on thei r solubilities, are correlated by the Soave-Redlich-E;wong equation of stat e with an association model. It is assumed that the system consists of supe rcritical CO2, solute monomer, solute dimer, hydrogen bonding species betwe en solute monomer and entrainer, and entrainer, The mole fractions of these species are determined by the equilibrium constants for dimerization of pa lmitic acid, and those For hydrogen bonding species between palmitic acid a nd ethanol obtained from FTIR spectroscopic study. The calculated results a greed with the experimental data.