Rapid remobilisation of plutonium from estuarine sediments

Hamilton−Taylor, John; Kelly, Mike; Mudge, Stephen M.; Bradshaw, Kris

doi:10.1016/0265-931x(87)90017-8

Cited by 33 publications

(7 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, Pu batch desorption experiments with goethite and hematite have indicated that less than 1% of the Pu associated with the mineral surface will be desorbed . Similarly, experiments with sediments from the Esk Estuary, UK showed that about 5% of Pu associated with the sediments (which was predominantly in the Pu(III)/(IV) oxidation state on the sediment surface) could be desorbed . Similar values were measured for Pu desorbed from Aiken, SC sediments where approximately 1–9% of adsorbed Pu was removed in batch experiments across a pH range from 2.4 to 8.4.…”

Section: Introductionmentioning

confidence: 62%

Plutonium Desorption from Mineral Surfaces at Environmental Concentrations of Hydrogen Peroxide

Begg

Zavarin

Kersting

2014

Environ. Sci. Technol.

View full text Add to dashboard Cite

Knowledge of Pu adsorption and desorption behavior on mineral surfaces is crucial for understanding its environmental mobility. Here we demonstrate that environmental concentrations of H2O2 can affect the stability of Pu adsorbed to goethite, montmorillonite, and quartz across a wide range of pH values. In batch experiments where Pu(IV) was adsorbed to goethite for 21 days at pH 4, 6, and 8, the addition of 5-500 μM H2O2 resulted in significant Pu desorption. At pH 6 and 8 this desorption was transient with readsorption of the Pu to goethite within 30 days. At pH 4, no Pu readsorption was observed. Experiments with both quartz and montmorillonite at 5 μM H2O2 desorbed far less Pu than in the goethite experiments highlighting the contribution of Fe redox couples in controlling Pu desorption at low H2O2 concentrations. Plutonium(IV) adsorbed to quartz and subsequently spiked with 500 μM H2O2 resulted in significant desorption of Pu, demonstrating the complexity of the desorption process. Our results provide the first evidence of H2O2-driven desorption of Pu(IV) from mineral surfaces. We suggest that this reaction pathway coupled with environmental levels of hydrogen peroxide may contribute to Pu mobility in the environment.

show abstract

Section: Introductionmentioning

confidence: 62%

Plutonium Desorption from Mineral Surfaces at Environmental Concentrations of Hydrogen Peroxide

Begg

Zavarin

Kersting

2014

Environ. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…For example, Pu(IV) and Pu(V) batch desorption experiments with goethite and hematite have indicated that less than 1% of the solid associated Pu will be desorbed (Lu et al, 1998). Similarly, experiments with sediments from the Esk Estuary, near Sellafield, UK showed that only about 5% of surface-associated Pu(IV) could be desorbed (Hamilton-Taylor et al, 1987). However, greater extents of Pu desorption have been reported for montmorillonite and silica, where up to 20% of Pu was desorbed after a period of 293 days at pH 8.3 (Lu et al, 2003).…”

Section: Introductionmentioning

confidence: 99%

Desorption of plutonium from montmorillonite: An experimental and modeling study

Begg

Zavarin

Kersting

2017

Geochimica et Cosmochimica Acta

View full text Add to dashboard Cite

“…1 excess of "dissolved" 238 Pu (<0.45 μπι) in low salinity waters and a depletion in the zone of intermediate salinities with respect to conservative dilution. In the Esk estuary, the same behaviour of Pu was observed at low salinities [4] and it was demonstrated that this excess could originate from sediments by desorption [5]. Dissolved Pu activities in low salinity waters show that the contribution of only 1-3% of the plutonium associated with the suspended matter is necessary to explain any excess (Table 2).…”

Section: Results and Interpretationmentioning

confidence: 55%

“…For example, measurements of Pu in the Esk estuary near the reprocessing plant of Sellafield show an excess in the 0.45 μηι filtered waters at low salinities with respect to conservative dilution [4], Experiments have demonstrated that plutonium associated with estuarine sediments is remobilized in low salinity waters [5]. The Seine estuary is also a macrotidal estuary and located in the area of influence of a reprocessing plant (La Hague).…”

Section: Introductionmentioning

confidence: 99%

Multiparametric Investigation of the Reactions of Plutonium under Estuarine Conditions

Garcia¹,

Boust²,

Moulin

et al. 1996

Radiochimica Acta

View full text Add to dashboard Cite

Several sampling campaigns were carried out in the Seine estuary in order to study the behaviour of plutonium isotopes versus salinity ( 23 "Pu and 239 ' 240 Pu), in 0.45 μηι filtered waters. During estuarine mixing, the plutonium has a non-conservative behaviour: plots of Pu activities versus salinity display an excess of dissolved 238 Pu (RI = «"p u / 2! " 4°P u > 1) in low salinity waters (0.5 and 1.5 g Γ 1 ) and a depletion (RI < 1) in the zone of intermediate salinities (8 to 15 g Γ')> with respect to conservative dilution.Laboratory experiments showed that Pu(V) present in seawater is reduced to the III, IV states and sorbed onto particles with a maximum in low salinity waters which could explain the depletion observed at intermediate salinity in the Seine estuary. Reduction occurs prior to sorption and is connected with the Seine river colloidal and dissolved species (humic acids). The Pu associated with estuarine sediments desorbs from the "oxidehydroxide" fraction in contact with river water, thus partly explains the plutonium excess measured in low salinity filtered waters of the Seine.

show abstract

Rapid remobilisation of plutonium from estuarine sediments

Cited by 33 publications

References 13 publications

Plutonium Desorption from Mineral Surfaces at Environmental Concentrations of Hydrogen Peroxide

Plutonium Desorption from Mineral Surfaces at Environmental Concentrations of Hydrogen Peroxide

Desorption of plutonium from montmorillonite: An experimental and modeling study

Multiparametric Investigation of the Reactions of Plutonium under Estuarine Conditions

Contact Info

Product

Resources

About