Separation of Light Lanthanoids by Centrifugal Partition Chromatography in 30% TBP Extraction System

Abstract

Abstract Separation of light lanthanoids (III) with centrifugal partition chromatography (CPC) in 30% tri-n-butyl phosphate (TBP) extraction system with the aid of salting-out agent lithium nitrate (LiNO3) was investigated. Carbon tetrachloride (CC14) and ndodecane were used as diluents to control the density difference between mobile and stationary phases. By a batch method, it was proved that distribution ratios (D) and separation factors (α) of several light lanthanoids increased with the LiNO3 concentration in 1 M (mol dm−3) nitric acid in the aqueous phase. Addition of CC14 to 30% TBP-n dodecane organic phase resulted in a decrease of the D values, holding the α values constant. On the basis of these data, separations of Ce, Pr and Eu with a CPC apparatus were successfully performed by decreasing the density difference. Although the chromatogram data differed considerably from the batch data owing to the concentration effect of the lanthanoids, satisfactory separation was obtained in 30% TBP-35% n do...