ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 36, Number 5
JKCSEZ 36(5)
October 20, 1992 

NH4+ form cation exchange resin was used to separate one rare earth element from the rare earth mixture solution using Ln-EDTA eluent. Rare earth mixture solution was passed through the resin bed and eluted with 0.1M La-EDTA solution as an eluent. In here all the rare earth element except lanthanum ion are eluted and lanthanum ion absorbed in resin bed is eluted using 0.1M EDTA solution. If Ce-EDTA solution instead of La-EDTA solution was used as an eluent, all the rare earth element except cerium ion are eluted and cerium ion is eluted with 0.1M EDTA solution. This method can be applied to separate the individual rare earth element from the mixture. The separation mechanism is as follows: Absorption : 3RNH4 ＋ Ln³⁺ = R3Ln ＋ 3NH4+, La-EDTA elution : R3Ln ＋ La-Y^- = R3La ＋ Ln-Y^-, EDTA elution : R3La ＋ HY^3- = La-Y ＋ RH ＋ 2R-.