During the last three decades, the interest of the chemical industry in processes with supercritical fluids (SCFs) has increased because of the advantages SCFs show in comparison to traditional organic solvents, like non-toxicity, what is very important in the food-industry. In order to design a process, phase equilibria data are needed. Since the measurement of phase equilibria data is very time-consuming and requires sophisticated equipments, it would be desirable to apply thermodynamic models, which are able to predict the phase equilibria behavior reliably. In this work, the solubilities and compressed liquid densities of palmitic acid in supercritical carbon dioxide were investigated in a temperature range from 40 to 55 °C and a pressure range from 10 to 25 MPa. The measurements were carried out in a static-synthetic sapphire cell combined with a vibrating tube densimeter. The experimental liquid densities are correlated with a six parameter volume explicit equation. The experimental solubilities are compared with the calculated values of the group-contribution equations of state PSRK and VTPR.

Keywords: SCF, palmitic acid, PSRK, VTPR

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