SEPARATION OF AM(III) AND EU(III) IN SYSTEMS WITH NEUTRAL BIDENTATE ORGANOPHOSPHORUS EXTRACTANTS BY COUNTERCURRENT CHROMATOGRAPHY

Liquid chromatography with a free stationary phase (LCFSP, countercurr ent chromatography) can be used to separate Am(III) and Eu(III) in sys tems with neutral bidentate organophosphorus extractants. If CHCl3 sol utions of tetraphenylmethylenediphosphine dioxide (TPMDPD) are used as the stationary phase, Eu(III) is first eluted by 0.5 M NH4SCN-1 M HCl and then Am(III) by 0.025 M hydroxyethylidenediphosphonic acid (HEDPA ) in water. If CHCl3 solutions of 1,2,4-tris(diphenylphosphinylmethyl) benzene (1,2,4-TDPPMB) are used as the stationary phase, the elements are separated by elution with 3 M HNO3 with Am eluting rst. both insta nces, 3-5 ml fractions contain 96-99% of one of the elements and no im purity of the other.