Exploiting the coordination chemistry of high-valent americium for actinide/lanthanide separations

Efficient americium (Am)/lanthanide (Ln) separation is highly pursued in advanced nuclear fuel cycle for minimizing the long-term radiotoxicity of nuclear waste and maximizing the utilization of nuclear resources. However, such a task is extremely challenging given the chemical similarity between the inherent thermodynamically stable Am(III) and Ln(III) ions. In recent years, interest in Am/Ln separation through oxidizing Am(III) to higher-valent states is reigniting due to theoretically considerable separation efficiency of this approach. This review summarizes the developments in preparation and stabilization of high-valent Am, especially the progresses in the exploitation of the coordination chemistry of these high-valent Am for effective Am/Ln separation. This review aims to inspire the search for efficient redox and coordination systems with more robust Am/Ln separation performance.