title: Plutonium(IV) sorption to montmorillonite in the presence of organic matter.
abstract: The effect of altering the order of addition in a ternary system of plutonium(IV), organic matter (fulvic acid, humic acid and desferrioxamine B), and montmorillonite was investigated. A decrease in Pu(IV) sorption to montmorillonite in the presence of fulvic and humic acid relative to the binary Pu-montmorillonite system, is attributed to strong organic aqueous complex formation with aqueous Pu(IV). No dependence on the order of addition was observed. In contrast, in the system where Pu(IV) was equilibrated with desferrioxamine B (DFOB) prior to addition of montmorillonite, an increase in Pu(IV) sorption was observed relative to the binary system. When DFOB was equilibrated with montmorillonite prior to addition of Pu(IV), Pu(IV) sorption was equivalent to the binary system. X-ray diffraction and transmission electron microscopy revealed that DFOB accumulated in the interlayer of montmorillonite. The order of DFOB addition plays an important role in the observed sorption/desorption behavior of Pu. The irreversible nature of DFOB accumulation in the montmorillonite interlayer leads to an apparent dependence of Pu sorption on the order of addition in the ternary system. This work demonstrates that the order of addition will be relevant in ternary systems in which at least one component exhibits irreversible sorption behavior.
authors.affiliation: Glenn T. Seaborg Institute, Physical and Life Sciences, Lawrence Livermore National Laboratory, PO Box 808 L-231, 94550 CA, USA. Electronic address: Boggs6@llnl.gov.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Boggs
authors.affiliation: Glenn T. Seaborg Institute, Physical and Life Sciences, Lawrence Livermore National Laboratory, PO Box 808 L-231, 94550 CA, USA.
authors.forename: Zurong
authors.initials: Z
authors.lastname: Dai
authors.affiliation: Glenn T. Seaborg Institute, Physical and Life Sciences, Lawrence Livermore National Laboratory, PO Box 808 L-231, 94550 CA, USA.
authors.forename: Annie B
authors.initials: AB
authors.lastname: Kersting
authors.affiliation: Glenn T. Seaborg Institute, Physical and Life Sciences, Lawrence Livermore National Laboratory, PO Box 808 L-231, 94550 CA, USA.
authors.forename: Mavrik
authors.initials: M
authors.lastname: Zavarin
mesh_terms: D000327:Adsorption; D001546:Bentonite / Q000737:chemistry*; D001578:Benzopyrans / Q000032:analysis*; D003676:Deferoxamine / Q000032:analysis*; D006812:Humic Substances / Q000032:analysis*; D046529:Microscopy, Electron, Transmission; D011005:Plutonium / Q000737:chemistry*; D012990:Soil Pollutants, Radioactive / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D001578:Benzopyrans; D006812:Humic Substances; D012990:Soil Pollutants, Radioactive; D001546:Bentonite; D011005:Plutonium; D003676:Deferoxamine; C005023:fulvic acid
keywords: Clay; Colloids; Humic acid; Plutonium; Siderophore; Sorption