Phase equilibrium measurements of sacha inchi oil (Plukenetia volubilis) and CO2 at high pressures

Abstract

New data on phase equilibria for Sacha inchi seed oil in carbon dioxide have been measured using a variable volume cell phase equilibria system at temperatures of 303, 313 and 323 K and at pressures ranging from 4.3 to 27.7 MPa. The CO2 mole fraction varied from 0.7488 to 0.9997. At the studied concentrations, phase transitions of vapor-liquid, liquid-liquid-vapor and liquid-liquid were observed. Sacha inchi oil contains 47% of omega-3 fatty acids, with a ratio of 0.76:1 for omega-6:omega-3, which is good for human health. The Peng-Robinson equation of state was used to describe the experimental data. A qualitative agreement was obtained between experimental and calculated data for the binary system CO2 and Sacha inchi seed oil. © 2011 AOCS.