STUDY OF THE REDUCTION-MECHANISM AND THE ADSORPTION PROPERTIES OF URANIUM(VI)-CUPFERRON COMPLEXES USING VARIOUS ELECTROCHEMICAL TECHNIQUES

The reduction mechanism of uranium(VI)-cupferron was studied by differ ent electrochemical techniques such as stripping voltammetry and cycli c voltammetry. It is proposed that the U(VI) ions in the form of adsor bed complexes with cupferron are reduced at -0.46 V to U(V). The furth er reduction to tl(III) is followed by a parallel catalytic reaction, which results in a chemical re-oxidation of the latter to U(V), with c upferron playing the double role of complexing and oxidizing agent. Th e strong adsorption properties of the complexes were studied by applyi ng the recently developed three-dimensional phase-sensitive alternatin g current voltammetry.