Potential Application of Kläui Ligands in Actinide Separations

Book · Mon Jul 31 04:00:00 EDT 2006

OSTI ID:894855

Lumetta, Gregg J; McNamara, Bruce K; Hubler, Timothy L; Wester, Dennis W; Li, Jun; Latesky, Stanley L

We have undertaken a systematic study of the complexation of Cp*Co[P(O)(OR)2]3- (Cp* = pentamethylcyclopentadienyl) ligands with f-block metal ions (i.e., lanthanides and actinides). As part of this work, the complexation of La3+ ion with Cp*Co[P(O)(OR)2]3- ligands has been studied as the alkyl group was systematically varied from methyl to n-propyl (R = -CH3, -CH2CH3, and -CH2 CH2CH3). For ligands in which R = -CH3 or -CH2CH3, complexes with ligand-to-La stoichiometries of 1:1 and 2:1 were formed. In contrast, only the 1:1 complex was isolated when R = CH2CH2CH3. A prototypical extraction chromatography resin containing Cp*Co[P(O)(OEt)2]3- (1b) has been prepared. The resin consists of 0.75 wt% 1b on Amberlite? XAD-7. This resin strongly sorbs Am3+ and Pu4+. The sorption of these ions decreases with increasing nitric acid concentration, but this effect is more pronounced for Am3+. This allows for convenient separation of Am3+ from Pu4+ by simple adjustments in the HNO3 concentration. The tripodal geometry of 1b disfavors the complexation of UO22+, so sorption of U(VI) by the 1b-containing resin is weak.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 894855
• Report Number(s): PNNL-SA-43257; 12298
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
AMERICIUM
COBALT COMPLEXES
EXTRACTION CHROMATOGRAPHY
Environmental Molecular Sciences Laboratory
Kläui ligand
LANTHANUM COMPLEXES
NITRIC ACID
ORGANIC ION EXCHANGERS
PLUTONIUM
RESINS
SORPTION
SORPTIVE PROPERTIES
actinide separation
americium
lanthanum
plutonium
uranium