Electrochemical oxidation of ²⁴³Am(III) in nitric acid by a terpyridyl-derivatized electrode

Christopher J Dares; Alexander M Lapides; Bruce J Mincher; Thomas J Meyer

doi:10.1126/science.aac9217

Electrochemical oxidation of ²⁴³Am(III) in nitric acid by a terpyridyl-derivatized electrode

Science. 2015 Nov 6;350(6261):652-5. doi: 10.1126/science.aac9217.

Authors

Christopher J Dares¹, Alexander M Lapides¹, Bruce J Mincher², Thomas J Meyer³

Affiliations

¹ Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
² Idaho National Laboratory, Aqueous Separations and Radiochemistry Department, Idaho Falls, ID, USA.
³ Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA. tjmeyer@unc.edu.

PMID: 26542564
DOI: 10.1126/science.aac9217

Abstract

Selective oxidation of trivalent americium (Am) could facilitate its separation from lanthanides in nuclear waste streams. Here, we report the application of a high-surface-area, tin-doped indium oxide electrode surface-derivatized with a terpyridine ligand to the oxidation of Am(III) to Am(V) and Am(VI) in nitric acid. Potentials as low as 1.8 volts (V) versus the saturated calomel electrode were applied, 0.7 V lower than the 2.6 V potential for one-electron oxidation of Am(III) to Am(IV) in 1 molar acid. This simple electrochemical procedure provides a method to access the higher oxidation states of Am in noncomplexing media for the study of the associated coordination chemistry and, more important, for more efficient separation protocols.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.