Fluid phase equilibria and mass transfer studies applied to supercritical fluid extraction of Illicium verum volatile oil

Supercritical fluid extraction (SFE) is one of the techniques used to obtain Illicium verum volatile oil, however, solubility of the volatile oil in CO2, one of the most important process variables from the SFE, is still unknown. In this work, vapor liquid equilibria experiments (VLE) were conducted in order to verify solubility of the major compound in the I. verum volatile oil, E-anethole, in CO2. In addition, SFE was carried with 750 g/h and 1500 g/h of CO2 at 308.15 K and 8000 kPa, 9000 kPa, 10,000 kPa and the antioxidant activity of the volatile oil accessed by the DPPH method. The VLE experimental data was modeled using the Peng–Robinson EOS (PR-EOS) with three mixing rules (vdW1, vdW2 and MKP). Moreover, SFE process was simulated using the equation proposed by Sovová and solubility data was compared with the values obtained by the PR-EOS.