ABSTRACT
Highly selective separations of Thallium (Tl) from accompanying elements are achieved by adsorption of the trivalent element on anion exchange resins from hydrochloric (HCl) or hydrobromic (HBr) acid media. By means of this technique Tl can be isolated quantitatively from geological, biological, and industrial materials. Suitable separations of Tl from matrices of this type are also obtained by the use of cation exchangers or chelating resins. Cation exchange separation procedures have been used in connection with the determination of Tl in rocks, minerals, and soils and in industrial products. When utilizing the nonadsorbability of Tl from dilute HCl media, it is necessary to carry out the separations in the presence of a holding oxidant to prevent reduction of the Tl to the adsorbadle monovalent state. Coeluted with the Tl are all anionic constituents of the solution, while essentially all cations are retained by the cation exchange resin.
