GROUP SEPARATION OF TRANSPLUTONIUM AND RARE-EARTH ELEMENTS BY LIQUID-CHROMATOGRAPHY WITH A FREE STATIONARY-PHASE USING 2,4,6-TRIS[DITOLYLPHOSPHORYL]-1,3,5-TRIAZINE

Methods are developed for group separation of trace quantities of tran splutonium (TPE) and weighable amounts of rare-earth elements (REE) by liquid chromatography with a free stationary phase in systems based o n bifunctional neutral organophosphorus compounds. Using a stationary phase of 2,4,6-Tris(ditolylphosphoryl)-1,3,5-triazine in CHCl3, REE ar e first eluted by 0.5 M NH4SCN-1 M HCl and then TPE by 0.025 M hydroxy ethylidenediphosphonic acid in H2O. The fractions contained similar to 100% of one of the groups without an impurity of the other. Use of th e same eluents and a CHCl3 solution of tetraphenylmethylenediphosphine dioxide as the stationary phase gave 95.4% pure REE and 97.5% pure TP E.