Abstract
Tetravalent and hexavalent uranium solubilities have been measured in cement-equilibriated water for pH values from 4 to 13. Tetravalent uranium solubilities at pH 12 have been measured by three experimental techniques: oversaturation, undersaturation and by the use of an electrochemical cell which controlled the redox conditions. The experimentally obtained data have been simulated using the thermodynamic equilibrium program HARPHRQ in conjunction with three different sets of thermodynamic data for uranium. In each case, differences were found between the predicted and measured uranium behaviour. For hexavalent uranium at high pH values the model suggested the formation of anionic hydrolysis products which led to the prediction of uranium solubilities significantly higher than those observed. Refinement of the thermodynamic data used in the model enabled the derivation of maximum values for the formation constants of these species under cementitious conditions. Similarly, the experimental data have been used to refine a model of tetravalent uranium solubility under cementitious near-field conditions. (author).
Baston, G M.N.;
Brownsword, M;
Cross, J E;
Hobley, J;
Moreton, A D;
Smith-Briggs, J L;
Thomason, H P
[1]
- AEA Decommissioning and Waste Management, Harwell (United Kingdom)
Citation Formats
Baston, G M.N., Brownsword, M, Cross, J E, Hobley, J, Moreton, A D, Smith-Briggs, J L, and Thomason, H P.
The solubility of uranium in cementitious near-field chemical conditions.
United Kingdom: N. p.,
1993.
Web.
Baston, G M.N., Brownsword, M, Cross, J E, Hobley, J, Moreton, A D, Smith-Briggs, J L, & Thomason, H P.
The solubility of uranium in cementitious near-field chemical conditions.
United Kingdom.
Baston, G M.N., Brownsword, M, Cross, J E, Hobley, J, Moreton, A D, Smith-Briggs, J L, and Thomason, H P.
1993.
"The solubility of uranium in cementitious near-field chemical conditions."
United Kingdom.
@misc{etde_10126962,
title = {The solubility of uranium in cementitious near-field chemical conditions}
author = {Baston, G M.N., Brownsword, M, Cross, J E, Hobley, J, Moreton, A D, Smith-Briggs, J L, and Thomason, H P}
abstractNote = {Tetravalent and hexavalent uranium solubilities have been measured in cement-equilibriated water for pH values from 4 to 13. Tetravalent uranium solubilities at pH 12 have been measured by three experimental techniques: oversaturation, undersaturation and by the use of an electrochemical cell which controlled the redox conditions. The experimentally obtained data have been simulated using the thermodynamic equilibrium program HARPHRQ in conjunction with three different sets of thermodynamic data for uranium. In each case, differences were found between the predicted and measured uranium behaviour. For hexavalent uranium at high pH values the model suggested the formation of anionic hydrolysis products which led to the prediction of uranium solubilities significantly higher than those observed. Refinement of the thermodynamic data used in the model enabled the derivation of maximum values for the formation constants of these species under cementitious conditions. Similarly, the experimental data have been used to refine a model of tetravalent uranium solubility under cementitious near-field conditions. (author).}
place = {United Kingdom}
year = {1993}
month = {May}
}
title = {The solubility of uranium in cementitious near-field chemical conditions}
author = {Baston, G M.N., Brownsword, M, Cross, J E, Hobley, J, Moreton, A D, Smith-Briggs, J L, and Thomason, H P}
abstractNote = {Tetravalent and hexavalent uranium solubilities have been measured in cement-equilibriated water for pH values from 4 to 13. Tetravalent uranium solubilities at pH 12 have been measured by three experimental techniques: oversaturation, undersaturation and by the use of an electrochemical cell which controlled the redox conditions. The experimentally obtained data have been simulated using the thermodynamic equilibrium program HARPHRQ in conjunction with three different sets of thermodynamic data for uranium. In each case, differences were found between the predicted and measured uranium behaviour. For hexavalent uranium at high pH values the model suggested the formation of anionic hydrolysis products which led to the prediction of uranium solubilities significantly higher than those observed. Refinement of the thermodynamic data used in the model enabled the derivation of maximum values for the formation constants of these species under cementitious conditions. Similarly, the experimental data have been used to refine a model of tetravalent uranium solubility under cementitious near-field conditions. (author).}
place = {United Kingdom}
year = {1993}
month = {May}
}