A TRUEX-Based Separation of Americium from the Lanthanides

作者：Mincher Bruce J^*; Schmitt Nicholas C; Case Mary E

来源：Solvent Extraction and Ion Exchange, 2011, 29(2): 247-259.

DOI：10.1080/07366299.2011.539146

• Actinide extraction
• americium
• americium oxidation
• sodium bismuthate
• TRUEX

The inextractability of the actinide AnO(2)(+) ions by the TRUEX solvent suggests the possibility of a separation of americium from the lanthanides using oxidation to Am(V). The only current method for the direct oxidation of americium to Am(V) in strongly acidic media is with sodium bismuthate. We prepared Am(V) over a wide range of nitric acid concentrations and investigated its solvent-extraction behavior for comparison to europium. While a separation is achievable in principal, the presence of macro amounts of cerium competes for the sparingly soluble oxidant and the oxidant itself competes for CMPO complexation. These factors conspire to reduce the Eu/Am separation factor from 40 using tracer solutions to 5 for extractions from the first-cycle raffinate simulant solution. To separate pentavalent americium directly from the lanthanides using the TRUEX process, an alternative oxidizing agent may be necessary.

• 出版日期2011