Anion-exchange Behavior of Nb, Ta, and Pa as Homologues of Db in HF/HNO3 Solutions

Abstract

To find suitable conditions for the experimental study of anion-exchange behavior of element 105, dubnium (Db), we have investigated anion-exchange behavior of the group-5 elements Nb, Ta, and their pseudo homologue Pa in HF/HNO3 media by a batch method using radiotracers of 95Nb, 179Ta, and 233Pa. Clearly different adsorption behavior was observed among those homologues in the fluoride ion concentrations of 1 •~ 10-6 M < [F-] < 2 •~ 10-2 M, suggesting that each eleeet forms different anionic complexes. Based on the observed distribution coeffi-