Separation of oleic acid and linoleic acid by solvent extraction

Oleic acid and linoleic acid were separated by extraction with the solvent systemn-heptane-dimethyl sulfoxide. The separation factor decreased with increasing concentrations of fatty acids in the dimethyl sulfoxide (DMSO) layer. At fatty concn of 0.60 and 16.02%, the separation factors of linoleic acid were found to be 2.18 and 1.28, respectively. The solvent could be removed by adding water to the extract. DMSO is very soluble in water while the fatty acids are only sparingly soluble. Thus DMSO and fatty acids are separated. A phase diagram for the system Unitol ACD-DMSO-water at 25C and 1 atm is given.