A Study of Solid-Liquid Phase Equilibria of Trivalent Lanthanide and Actinide Ions in Carbonate Systems

Runde, Wolfgang; Meinrath, G.; Kim, J. I.

doi:10.1524/ract.1992.5859.1.93

Cited by 73 publications

(49 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Under the air equilibrium condition, the solid phase of REE that regulates the total concentration of dissolved REE species may be LnOHCO3 (Ln = REE). 38 The total concentration of REE in the aqueous phase equilibrated with LnOHCO3 was calculated for Eu(III), since the solubility data of LnOHCO3 were available for Eu(III). 38 As a result, the Eu(III) concentration of 100 ppb is below the solubility at pH < 7.6 ( Fig.…”

Section: Background Datamentioning

confidence: 99%

“…38 The total concentration of REE in the aqueous phase equilibrated with LnOHCO3 was calculated for Eu(III), since the solubility data of LnOHCO3 were available for Eu(III). 38 As a result, the Eu(III) concentration of 100 ppb is below the solubility at pH < 7.6 ( Fig. 1), showing that all of the Eu(III) can be dissolved in our experimental system.…”

Section: Background Datamentioning

confidence: 99%

See 1 more Smart Citation

Distribution Pattern of Rare Earth Ions between Water and Montmorillonite and Its Relation to the Sorbed Species of the Ions

2004

View full text Add to dashboard Cite

Speciation is important for describing chemical reactions in the environment and for estimating the environmental behavior of metal ions. For REE and actinides(III), particulate matter can be the main carrier governing their migration in a natural aquifer in addition to complexed species in an aqueous phase. [1][2][3] However, the chemical species of REE or actinides(III) at a solid-water interface is still not clearly understood on a molecular scale. Although the complexed species in an aqueous phase can be easily assessed by solution chemistry data, 3,4 the complex nature of particulate matter often prevents us from precisely describing the sorption reaction of REE, or actinides(III). Regarding this point, the REE distribution patterns plotting the distribution coefficients between the solid and aqueous phases in the order of atomic number could be a clue to clarify the REE species at the solid-water interface, since the REE distribution patterns reflect the chemical species of REE at the solid-water interface due to a systematic variation of the chemical character across the REE series. In this study, we investigated the possibility of using the REE distribution patterns to estimate the species of REE, or actinides(III), at a montmorillonite-water interface as an example of a solid-water system in a natural aquifer.It is considered that three features in the REE (including Y) patterns can be useful to estimate the REE species at the solidwater interface: (1) the slope of the REE pattern, (2) the tetrad effect, and (3) the Y/Ho ratio, the details of which are described in the next section. Although the sorption of selected REE on montmorillonite has been studied, [5][6][7][8] there have been few studies on the sorption of a complete REE series where REE patterns are employed to estimate the sorbed species, despite that REE patterns are highly relevant to the REE species. A part of the results were presented in Takahashi et al., but Y data were not included. 9 A similar aspect was also presented by Coppin et al., suggesting a correlation between the slope of the REE pattern and the REE species sorbed on clay minerals. 10 However, Coppin et al. have not clearly referred to the effectiveness of using the tetrad effect or the Y/Ho ratio for REE speciation, which is discussed in the present study. 10 Here, it is reported that the variation of the REE patterns is closely correlated with structural information on REE at the montmorillonite-water interface. In addition, the variation of the REE distribution patterns in the presence of humic acid was also included in this paper. Humic acid is another important constituent in a natural aquifer that can influence the REE behavior in the hydrosphere. [11][12][13][14] The relation between the REE patterns and the REE species at the solid-water interface was consistent with spectroscopic data obtained by laser-induced fluorescence for Eu(III) and Cm(III) species at the solid-water interface. These REE (rare earth element) distribution coefficients (Kd) between the aqueous p...

show abstract

Section: Background Datamentioning

confidence: 99%

Section: Background Datamentioning

confidence: 99%

Distribution Pattern of Rare Earth Ions between Water and Montmorillonite and Its Relation to the Sorbed Species of the Ions

2004

View full text Add to dashboard Cite

show abstract

“…Models to describe the equilibria of trivalent lanthanidedactinides in carbonate systems have been presented (Runde et al 1992). The solubility products of hydroxocarbonates determined at a CO, partial pressure of 0.03% were found to be: log K, = -19.94 f 0.16 for NdOHCO,, log K, = -20.18 f 0.09 for EuOHCO,.…”

Section: A Solubility Productsmentioning

confidence: 99%

“…The solubility products of carbonates, which can be applied at a CO, partial pressure range from 1 .O% to loo%, were reported by Runde et al (1992) to be:…”

Section: A Solubility Productsmentioning

confidence: 99%

Summary Report Geochemistry/Transport Tests, Milestone Sp23qm3 (Revised),november 18, 1997

Doe¹

1997

View full text Add to dashboard Cite

“…In the presence of carbonate two Am compounds have been observed, the carbonate Am 2 (CO 3 ) 3 and the hydroxy-carbonate AmOHCO 3 . They have solubility products (log K sp ) of -29.45 and -18.70 respectively under CO 2 partial pressures of both 1 % and 100 % (Runde et al, 1992). Kim et al, (1994) while the hexagonal form has a value of -25.5 (±1.1).…”

Section: Introductionmentioning

confidence: 99%

Fate of Contaminants in Contact with West Valley Grouts

Fuhrmann¹,

Gillow²

2009

View full text Add to dashboard Cite

A Study of Solid-Liquid Phase Equilibria of Trivalent Lanthanide and Actinide Ions in Carbonate Systems

Cited by 73 publications

References 11 publications

Distribution Pattern of Rare Earth Ions between Water and Montmorillonite and Its Relation to the Sorbed Species of the Ions

Distribution Pattern of Rare Earth Ions between Water and Montmorillonite and Its Relation to the Sorbed Species of the Ions

Summary Report Geochemistry/Transport Tests, Milestone Sp23qm3 (Revised),november 18, 1997

Fate of Contaminants in Contact with West Valley Grouts

Contact Info

Product

Resources

About