Studies of Applicability of Strongly and Weakly Basic Polystyrene and Polyacrylate Anion Exchangers for Separation of Y(edta)~- from Sm (edta)~- Complexes

摘要

The rare earth element complexes with EDTA of the Ln (edta)~- type show an unusual sequence of affinity for the polystyrene anion exchangers independent of stability constant values. Taking into account the position of Y(III) and Sm(III) in the affinity series, for the polyacrylate and polystyrene anion exchangers the distribution coefficients (Dc)of these complexes were determined. Taking into consideration their Dc values, the purification of Y(III) from Sm(III) in the macro-micro system on the polyacrylate and polystyrene strongly and weakly basic, gel and macroporous anion exchangers was studied. Using the above method it is possible to obtain about 114g Y_2O_3 purified from Sm_2O_3 on 1 dm~3 of Amberlite IRA 68 in the H_2 edta~(2-) form. However, the strongly basic gel anion exchanger Dowex 2 * 8 proved to be most effective of the polystyrene anion exchangers in sorption and separation of the Y (edta)~- and Sm (edta)~- complexes. On 1 dm~3 of this anion exchanger in the H_2 edta~(2-) form it is possible to obtain above 212 g Y_2O_3 purified from Sm_2O_3.