SEPARATION OF THE RARE EARTHS, Cd(Ⅱ),Co(Ⅱ), Pb(Ⅱ), Cu(Ⅱ), Zn(Ⅱ), U(Ⅵ) AND Th(Ⅳ)BY THIN-LAYER CHROMATOGRAPHY

In this paper is reported a method for the separation of the rare earths, Cd(Ⅱ), Co(Ⅱ), Pb(Ⅱ), Cu(Ⅱ), Zn(Ⅱ), U(Ⅵ) and Th(Ⅳ) by using thin-layer chromatography. When the optimum volume ratio of each component of the developing solvent of mono tetradecyl phosphoric acid-ethyl ether-concentrated HNO3 is selected to be 4.0:40.0:0.8, Cd(Ⅱ) or Co(Ⅱ), Pb(Ⅱ), Cu(Ⅱ) and Zn(Ⅱ) are satisfactorily separated from the rare earths (La-Gd) despite being present in 105 fold excess over them, and the adjacent rare earths of La-Gd are easily separated. When the volume ratio of each component of the developing solvent is selected to be 2.0:42.0:2.5, U(Ⅵ) or Th(Ⅳ) can be completely separated from the rare earths (Tb-Lu) despite being present in 105 fold excess over them, and the adjacent rare earths of Tb-Lu also are completely separated.