Researchers in UCI’s Department of Chemical Engineering/Material Science have developed a process to separate americium (Am) from trivalent lanthanides, both present in spent nuclear fuel. This separation is necessary for future nuclear fuel cycles.
The oxidation of americium in spent nuclear fuel is not new but the problem is that the higher oxidation states of americium tend to degrade the chemicals used for liquid extraction. Thus the combination of oxidation of Am with liquid extraction is problematic. UCI researchers have developed a process combining oxidation of Am from +3 to a higher oxidation state of +4 or +6 followed by selective extraction through a membrane with the general idea being to use an extraction membrane where the bulk of the organic solution is protected from the oxidizing environment.
Nuclear fuel processes
The bulk organic solvent is protected from the aggressive oxidizing aqueous solution the residence time that the oxidized americium spends in the organic phase is reduced.