Determination of radiocerium in fission products by extraction chromatography using di-(2-ethylhexyl)phosphoric acid

An extraction chromatographic method is described for the determination of cerium in a fission product mixture. Cerium(IV) is separated on a column of siliconized kieselguhr saturated with di-(2-ethylhexyl)phosphoric acid (HDEHPA). After washing the column with a mixture of sodium bromate and nitric acid, cerium is eluted by a mixture of 5M HNO₃ and 0.1M ascorbic acid. The optimum conditions for the quantitative sorption and elution of cerium were found, and the reproducibility of the yield was verified. The influence of other fission and corrosion products (Mg, Fe, Al, U) on the sorption and elution of cerium was studied. The method has been successfully applied for the determination of cerium in artificial and natural mixtures of fission products.