An experimental investigation into the solubility of Moringa oleifera oil in supercritical carbon dioxide

The solubility of Moringa oleifera oil in supercritical CO2 was investigated using a laboratory scale supercritical fluid extraction system operating at temperatures from 333 K to 373 K and pressures from 20 to 50 MPa. The oil solubility was found to be between 0.64 and 12.68 (g/kg CO2). The results showed that the solubility increased with increasing pressure under isothermal conditions. However, the effect of temperature showed different trends depending on the pressures. To generalise the experimental results, four models were employed to correlate the solubility data, including the Peng-Robinson equation of state and three density based models, namely, the Chrastil, del Valle and Aguilera, Adachi and Lu models. While all four models correlated the experimental data very well, the del Valle and Aguilera model showed the best fit. The Peng-Robinson equation of state enabled a thermodynamic explanation of the observed experimental trends of the variations in the M. oleifera oil solubility in supercritical CO2.© 2014 Elsevier Ltd. All rights reserved.