Sorption behaviour of rutherfordium and thorium from HCl/Hf containing aqueous solution

Abstract The sorption was studied of element 104 (rutherfordium, Rf) and thorium on the strongly acidic cation exchanger DOWEX 50×8. The experiments were carried out on-line. Rf is strongly retained on cation exchange resins from diluted HCl/HF solutions in a concentration range of 0.05 to 0.1 M HCl and HF concentrations up to 0.01 M. This behaviour is similar to its pseudohomologue thorium and very different from its lighter homologue hafnium which is desorbed from DOWEX 50×8 at HF concentrations above 10 −3 M. The tested ion exchange system is suitable for fast on-line separation of element 106 (seaborgium, Sg) from all other contaminations and its decay product Rf. It, therefore, allows the indirect identification of Sg.