Determination of plutonium oxidation states at trace levels pertinent to nuclear waste disposal

Nitsche, H.; Lee, S. C.; Gatti, R.C.

doi:10.1007/bf02035515

Cited by 80 publications

(60 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, oxidation state analyses were preformed in the GW and the GWCW solution samples after 20 hours. The redox speciation of plutonium was studied using TTA and di(2-ethylhexyl)orthophosphoric acid (HDEHP) as extractants [21,22].…”

Section: Methodsmentioning

confidence: 99%

Cs and Pu migration through engineered and natural barriers

Lujaniené¹,

Motiejūnas²,

Šapolaitė³

et al. 2005

Lith. J. Phys.

View full text Add to dashboard Cite

Performance assessment of radioactive waste disposal requires modelling of long-term migration of radionuclides through the engineered barriers and the geological environment. The chemical complexity of sorption-desorption processes is usually reduced to integrated parameter distribution coefficients (K d ). There are a great number of publications on K d determination, however, the existing data on K d of radionuclides on different geological materials are for general understanding only and are not very useful for performance assessment since the changes of the geological conditions result in a variability of K d values by two orders of magnitude. In order to obtain realistic sorption data sets for safety-relevant radionuclides present in a cement/concrete based repository some preliminary studies were carried out. The development of sorption database for the near-surface repository was started with measurements of cesium and plutonium K d values. Samples of loam available at the Galilaukė site (Quaternary deposits) and Triassic clay from industrial Šaltiškiai quarry selected as a candidate for the engineered barrier of Lithuanian near-surface repository were taken for laboratory investigations. Several experiments were performed in order to determine the chemical composition of cement water which could originate from infiltration of precipitation and from contact of groundwater with concrete. More than 100 batch sorption experiments were conducted with two clay samples. Cs and Pu K d values were determined under a wide range of geochemical conditions. Changes in the geochemical conditions resulted in the variability of Cs and Pu K d values.

show abstract

Section: Methodsmentioning

confidence: 99%

Cs and Pu migration through engineered and natural barriers

Lujaniené¹,

Motiejūnas²,

Šapolaitė³

et al. 2005

Lith. J. Phys.

View full text Add to dashboard Cite

show abstract

“…The Pu(IV) fraction was calculated by difference. Separation of Pu oxidation states by solvent extraction was performed using 0.5 M bis-(ethylhexyl)-phosphoric acid (HDEHP) in xylene and 0.025 M 4-benzyol-3-methyl-1-phenyl-2-pyrazolin-5-one (PMBP) in xylene as the extractants (Bertrand and Choppin, 1982;Foti and Freiling, 1964;Neu et al, 1994;Nitsche et al, 1988). The Pu oxidation state distribution in the working solution was determined using both HDEHP and PMBP as extractants.…”

Section: Pu Oxidation State Analysismentioning

confidence: 99%

Development of a Composite Non-Electrostatic Surface Complexation Model Describing Plutonium Sorption to Aluminosilicates

Powell¹,

Kersting²,

Zavarin³

et al. 2008

View full text Add to dashboard Cite

“…Due to its slowness, the separation by electrodeposition was seldom used for pre-concentration [66]. The co-precipitation method proved particularly useful for separation of different oxidation states of radionuclides in natural waters [67][68][69]. For instance, co-precipitation with praseodymium fluoride, or zirconium iodate, was used for separations of Pu(III) and Pu(IV) from Pu in higher valence states [70], The selectivity of separation of ionic, from colloidal species, by this method may be doubtful.…”

Section: Methods For Direct Speciation Analysis Of Aerosolsmentioning

confidence: 99%

“…When using other methods, possible influences on solution equilibrium should be checked. Under these conditions, high performance liquid chromatography (HPLC; [147]), solvent extraction [69,148,149], ion exchange [148,150], gel chromatography [148,151], paper chromatography [152], and adsorption [153,154] were successfully used for analysis of speciation of radionuclides in natural and waste waters.…”

Section: Model Experiments For Aqueous Speciationmentioning

confidence: 99%

Speciation of Radionuclides in the Environment

Gunten

Beneš

1995

Radiochimica Acta

View full text Add to dashboard Cite

Methods for the determination of the speciation of radionuclides in aerosols, in aquatic solutions, in sediments, soils and rocks are reviewed. At present, most of the results about speciation are deduced from model calculations, model experiments, and separation of species (forms) of radionuclides, e.g., by sequential extraction procedures. Methods of direct determination of speciation of radionuclides (e.g., by laser induced spectroscopy) are in general not yet sensitive enough for a measurement of the very low concentrations of radionuclides in the environment. The methodological part of this paper is followed by a review of the very abundant literature about speciation of important radionuclides in the environment, i.e., in the atmosphere, hydrosphere and lithosphère. The review does not include the biosphere. Literature up to spring 1993 is included (with a few more recent additions).

show abstract

Determination of plutonium oxidation states at trace levels pertinent to nuclear waste disposal

Cited by 80 publications

References 14 publications

Cs and Pu migration through engineered and natural barriers

Cs and Pu migration through engineered and natural barriers

Development of a Composite Non-Electrostatic Surface Complexation Model Describing Plutonium Sorption to Aluminosilicates

Speciation of Radionuclides in the Environment

Contact Info

Product

Resources

About