Process for separating mixed fatty acids from deodorizer distillate using urea

摘要

A process is described for separating deodorizer distillates, which are byproducts from processing vegetable and animal fats and oils, into a light fraction enriched in fatty acids and a heavy fraction enriched in tocopherols and sterols. Melted deodorizer distillate is added to a heated solution of urea dissolved in alcohol. The solution is preferably non-aqueous but may contain small quantities of water as an impurity. A crystalline complex of urea and fatty acid is formed which is removed from the solution and dried. The remaining mother liquor is saved for subsequent processing. The dried crystals are dissolved in water to yield an organic layer of fatty acids and an aqueous layer of urea. An organic fraction rich in tocopherols and sterols is separated in the same manner from the mother liquor, which was saved previously, by evaporating the alcohol to form a residue, mixing the residue with water and separating the organic layer.