Process Analysis and Phase Equilibria for the Removal of Chemicals from Fatty Oils Using Near-Critical Solvents

• Published in: Industrial & engineering chemistry research Vol. 39; no. 8; pp. 3024 - 3033
• Main Authors: Espinosa, S, Bottini, S. B, Brignole, E. A
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 07-08-2000
• Subjects: Biological and medical sciences; Biotechnology; Chemistry; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General and physical chemistry; Liquid-vapor equilibria; Methods. Procedures. Technologies; Others; Phase equilibria; Various methods and equipments; Palm kernel oil; Parameter estimation; Carbon dioxide; Temperature effect; Group contribution method; Partition coefficient; Experimental study; Solvent extraction; Vegetal oil; Optimization; Pressure effect; Equations of state; Thermodynamic model; Liquid vapor equilibrium; Supercritical solvent; Thermodynamic properties; Phase equilibrium; Supercritical fluid extraction; Propane
• ISSN: 0888-5885; 1520-5045
• DOI: 10.1021/ie000014d

The use of near-critical CO2 and propane for the removal of chemicalspollutants, undesirable or valuable productsfrom fatty oils is studied. The process conditions are discussed, on the basis of phase equilibrium predictions from a group contribution equation of state. The extension of the equation to cover systems with large differences in molecular size requires the use of revised parameters. With the new parameters, a good correlation of phase equilibrium data for all of the binaries involved in the process was achieved. Distribution coefficients of different chemicals between the oil and solvent phases were predicted, and optimum process conditions were explored. The extraction with propane requires the operation above the lower critical end-point temperature of the binary fatty oil−propane system, to have liquid−liquid or liquid−near-critical fluid phase immiscibility. The process analysis indicates that there are optimum operating pressures that minimize solvent requirements and fatty oil losses in the extract.