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Uranyl binding to humic acid under conditions relevant to cementitious geological disposal of radioactive wastes

Published online by Cambridge University Press:  05 July 2018

A. Stockdale  and
N. D. Bryan
A. Stockdale*
Affiliation:
Centre for Radiochemistry Research, School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK
N. D. Bryan
Affiliation:
Centre for Radiochemistry Research, School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK
*
*E-mail: [email protected]
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Abstract

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Few studies have sought to investigate the potential for dissolved organic matter (DOM) to bind (and thus potentially transport) radionuclides under the high pH regimes that are expected in cementitious disposal. We have used equilibrium dialysis to investigate uranyl binding to humic acid over a pH range of ∼10 to 13. The experimental results provide evidence that DOM can bind uranyl ions over this pH range, including in the presence of competing ions. There is a general decrease in binding with increasing pH, from ∼80% of total uranyl bound at pH 9.8 to ∼10% at pH 12.9. Modelling of the system with WHAM/Model VII can yield representative results up to pH ∼10.5.

Keywords

disposalhumic acidorganic matterradioactive wasteuranium speciationuranyl ion
Type
Research Article
Information
Mineralogical Magazine , Volume 76 , Issue 8 , December 2012 , pp. 3391 - 3399
Creative Commons
Creative Common License - CCCreative Common License - BY
© [2012] The Mineralogical Society of Great Britain and Ireland. This is an open access article distributed under the terms of the Creative Commons Attribution (CC BY) licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2012

References

Dierckx, A., Maes, A. and Vancluysen, J. (1994) Mixed complex formation of Eu3+ with humic acid and a competing ligand. Radiochimica Acta, 66/67, 149–156.Google Scholar
Duro, L., Grivé, M., Cera, E., Doménech, C. and Bruno, J. (2006) Update of a Thermodynamic Database for Radionuclides to Assist Solubility Limits Calculation for Performance Assessment. SKB Technical Report TR-06–17. Swedish Nuclear Fuel and Waste Management Company (SKB), Stockholm, Sweden.Google Scholar
Glasser, F.P., Marchand, J. and Samson, E. (2008) Durability of concrete-degradation phenomena involving detrimental chemical reactions. Cement and Concrete Research, 38, 226–246.CrossRefGoogle Scholar
Glaus, M.A., Hummel, W. and Van Loon, L.R. (1995) Equilibrium dialysis-ligand exchange: adaptation of the method for determination of conditional stability constants of radionuclide-fulvic acid complexes. Analytica Chimica Acta, 303, 321–331.CrossRefGoogle Scholar
Glaus, M.A., Hummel, W. and Van Loon, L.R. (1997) Experimental determination and modelling of trace metal-humate interactions: a pragmatic approach for applications in groundwater. Paul Scherrer Institute Report 97–13. Paul Scherrer Institute, Villigen, Switzerland.Google Scholar
Horwitz, E.P., Dietz, M.L., Chiarizia, R., Diamond, H., Essling, A.M. and Graczyk, D. (1992) Separation and preconcentration of uranium from acidic media by extraction chromatography. Analytica Chimica Acta, 266, 25–37.CrossRefGoogle Scholar
Jacques, D., Wang, L., Martens, E. and Mallants, D. (2010) Modelling chemical degradation of concrete during leaching with rain and soil water types. Cement and Concrete Research, 40, 1306–1313.CrossRefGoogle Scholar
Lofts, S. and Tipping, E. (2011) Assessing WHAM/ Model VII against field measurements of free metal ion concentrations: model performance and the role of uncertainty in parameters and inputs. Environmental Chemistry, 8, 501–516.CrossRefGoogle Scholar
Marang, L., Reiller, P.E., Eidner, S., Kumke, M.U. and Benedetti, M.F. (2008) Combining spectroscopic and potentiometric approaches to characterize competitive binding to humic substances. Environmental Science and Technology, 42, 5094–5098.CrossRefGoogle ScholarPubMed
Marang, L., Eidner, S., Kumke, M.U., Benedetti, M.F. and Reiller, P.E. (2009) Spectroscopic characterization of the competitive binding of Eu(III), Ca(II), and Cu(II) to a sedimentary originated humic acid. Chemical Geology, 264, 154–161.CrossRefGoogle Scholar
Pérez-Bustamante, J.A. (1971) Anomalous ion-exchange behaviour exhibited by aged acid-free uranyl nitrate solutions. Mikrochimica Acta, 3, 455–463.CrossRefGoogle Scholar
Rao, G.R. and Choppin, L.F. (1984) Complexation of pentavalent and hexavalent actinides by fluoride. Radiochimica Acta, 37, 143–146.Google Scholar
Shand, P. and Edmunds, W.M. (2008) The baseline inorganic chemistry of European groundwaters. Pp. 22–58.in: Natural Groundwater Quality (W.M. Edmunds and P. Shand , editors). Blackwell Publishing, Oxford, UK.Google Scholar
Stockdale, A., Bryan, N.D. and Lofts, S. (2011) Estimation of Model VII humic binding constants for Pd2+, Sn2+, U4+, NpO2 2+, Pu4+ and PuO2 2+. Journal of Environmental Monitoring, 13, 2946–2950.CrossRefGoogle Scholar
Tipping, E. (1994) WHAM - a chemical equilibrium model and computer code for waters, sediments and soils incorporating a discrete-site electrostatic model of ion-binding by humic substances. Computers and Geosciences, 20, 973–1023.CrossRefGoogle Scholar
Tipping, E., Lofts, S. and Sonke, J. (2011) Humic Ion- Binding Model VII: a revised parameterisation of cation-binding by humic substances. Environmental Chemistry, 8, 225–235.CrossRefGoogle Scholar
Zeh, P., Czerwinski, K.R. and Kim, J.I. (1997) Speciation of uranium in Gorleben groundwaters. Radiochimica Acta, 76, 37–44.CrossRefGoogle Scholar