A highly efficient in situ redox stabilization strategy for Am-Cm separation using AgBiO 3 .

AgBiO 3 is reported for the exclusive oxidation of Am 3+ → AmO 2 + at near-neutral pH conditions. Literature methods of AmO 2 + generation are generally two-step processes; i.e. , Am 3+ → AmO 2 2+ oxidation followed by AmO 2 2+ → AmO 2 + reduction. These methods for Am 3+ → AmO 2 + oxidation use high temperatures (80-100 °C) and/or several reagents, causing the in situ presence of the AmO 2 + -complex rather than the AmO 2 + aq ions. This not only interferes with the much-needed Am-Cm selectivity but also limits the use of AmO 2 + aq in any other experimental study. The single-step Am 3+ → AmO 2 + oxidation in the present work using AgBiO 3 is done at 25 °C in a non-complexing medium at pH ∼4, making it a first-of-its-kind report. Am-Eu and Am-Cm separation in a single contact, with a separation factor >10 4 , was achieved using the present method, which is unprecedented among aqueous feed solutions. The AmO 2 + generated using the present method under non-complexing pH conditions makes it also suitable for exploring the fundamental chemistry of the higher valent americyl ion. A complexation study using the thus-generated AmO 2 + ion with acetate ion supports the concept.