A comparative study of ion-exchange behavior of Hf and Pb as homologs of elements 104 (Rf) and 114, respectively, in solutions of hydrohalic acids. Relativistic effects

Abstract

Ion-exchange behavior of Hf and Pb as homologs of elements 104 (Rf) and 114, respectively, and of some other actinides in solutions of hydrohalic acids was studied in relation to the kind and concentra tion of the acid, solution composition, and nature of the ion exchanger. The optimal conditions for isolation, separation, and preconcentration of ultrasmall amounts of transactinide elements from their solutions in HF, HCl, and HBr were found. A scheme for on-line isolation of element 114 and superheavy elements with Z = 108−116, followed by identification by “long-lived” decay products, was developed using as a model the repeated continuous isolation of 211Pb from its parent radionuclide 227Ac in dilute HBr. Based on comparative study of the ion-exchange behavior of Hf and Pb as typical d and p elements, respectively, in solutions containing various halide ligands, the possibility of estimating the contribution of the relativistic effects to the chemical behavior of Rf in dilute solutions of HBr was discussed.