Recovery of Lecithin from the Lecithin - Cadmium Chloride Complex

Abstract

ALTHOUGH cadmium chloride has been in use at least since 1868 as a precipitant for lecithin, no completely satisfactory method for the removal of cadmium chloride from the complex formed in this manner has been devised. Strecker¹ used hydrogen sulphide to precipitate the cadmium. Bergell², in 1900, made use of ammonium carbonate, and Levene and Simms³, in 1921, introduced the procedure in recent common use, namely, treatment of a chloroform solution of lecithin – cadmium chloride with dry ammonia – methanol solution, both procedures resulting in the precipitation of a cadmium ammonium chloride complex. All these methods, in addition to resulting in poor yields, expose the easily oxidizable and labile lecithin to undesirably harsh treatment, with the result that, however pure the lecithin – cadmium chloride complex may have been, the lecithin finally isolated is once more somewhat impure.