Supercritical Processing of Fatty Oils: Phase Equilibrium Engineering

P. HEGEL; G. SOTO; A. VELEZ; G. MABE; S. PEREDA; S. BOTTINI

San Fransisco

Simposio; ISSF 2012 10th International Symposium on Supercritical Fluids; 2012

Virginia Commonwealth University

Supercritical fluids (SFs) play an important role in the search of new alternatives for the processing of fatty materials. Both, reaction and separation processes can benefit from the good transport properties of SFs and the possibility of tuning solvent capacity and selectivity by changes in temperature, pressure and composition. Neutral and polar lipids form asymmetric mixtures with traditional SFs (i.e. CO2, propane). These mixtures are likely to present partial liquid miscibility, reaching three fluid phase regions. Knowledge of the phase boundaries of these systems is essential to select adequate process operating conditions. The need is for both, experimental data and reliable thermodynamic models. In this presentation the benefits of the phase equilibrium engineering of supercritical extraction, fractionation and reaction processes of fatty oils are addressed. Examples are shown for the supercritical alcoholysis of lipids, the fractionation of glycerids and the extraction of oils from oil-seeds. Experimental results are analyzed on the light of thermodynamic property predictions by a group-contribution equation of state.