Development of Solid Phase Extraction Materials for Actinide and Lanthanide Separations

Jennifer Shusterman, University of California, Berkeley

The advancement of separation systems for actinides and lanthanide-fission products is necessary for treatment of legacy defense waste and spent nuclear fuel to improve stewardship of these materials. Current nuclear fuel cycle separations generally use liquid-liquid extraction systems, which generate large volumes of hazardous mixed waste. We are focused on solid-liquid extraction systems, which are expected to produce less waste and have improved extraction efficiencies. The solid phase extractant consists of a mesoporous (2-50 nm) silica support that is organically modified by covalently bonding ligands to the surface. Our current ligands of interest are oxygen-donor complexants that have shown promise in the nuclear fuel cycle for separations of trivalent actinides and lanthanides. Characterization of the unfunctionalized and functionalized materials will be presented. The liquid phase for these separations contains the metal of interest in nitric or hydrochloric acid media with varying ionic strengths. Ideally these materials will extract trivalent actinides and lanthanides from high concentrations of nitric acid to mimic nuclear waste streams. The work that will be presented here focuses on the sorption of Eu(III) and Am(III) with these organically modified silica materials. Future work will include Np(V), Pu(IV), Pu(VI), and Cm(III) interactions with these materials.

Abstract Author(s): Jennifer Shusterman, Anthony Bruchet, Harris Mason, Eva Uribe, Heino Nitsche