Separation of major impurities Ce, Pr, Nd, Sm, Al, Ca, Fe, and Zn from La using bis(2-ethylhexyl)phosphoric acid (D2EHPA)-impregnated resin in a hydrochloric acid medium

The chromatographic separation of the impurities Ce, Pr, Nd, Sm, Zn, Al, Ca, and Fe from La was investigated using bis(2-ethylhexyl)phosphoric acid (D2EHPA)-impregnated resin as the stationary phase. The distribution coefficients of the study elements as a function of the concentration of the HCl solution were obtained by batch experiment and their separation factors were evaluated based on the distribution coefficients in order to estimate the potential for separation from La. The chromatographic separation revealed that only La is eluted with 0.15 M HCl. The optimum conditions for separation at the room temperature are as follows: a resin bed with a height of 180 mm and diameter of 25 mm; 1800 mL of 0.15 M HCl solution as an eluent; and a flow rate of 1 mL min(-1). It was confirmed that the impurities Ce, Pr, Nd, Sm, Zn, Al, Ca, and Fe were eliminated completely from La when the recovery yield of La was 90%. (C) 2009 Elsevier B.V. All rights reserved.