Researchers at the University of North Carolina at Chapel Hill have adapted a technology developed for solar energy in order to selectively remove one of the trickiest and most-difficult-to-remove elements in nuclear waste pools across the country, making the storage of nuclear waste safer and nontoxic – and solving a decades-old problem.
The work, published in Science, not only opens the door to expand the use of one of the most efficient energy sources on the planet, but also adds a key step in completing the nuclear fuel cycle – an advance, along with wind and solar, that could help power the world’s energy needs cleanly for the future.
Ref: Electrochemical oxidation of 243Am(III) in nitric acid by a terpyridyl-derivatized electrode. Science (6 November 2015) | DOI: 10.1126/science.aac9217
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.