Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-19T09:10:38.451Z Has data issue: false hasContentIssue false

The role of uranium peroxide studtite on the retention of Cs, Sr and Se(VI)

Published online by Cambridge University Press:  15 February 2011

Javier Gimenez
Affiliation:
Chemical Engineering Department, Universitat Politecnica de Catalunya, 08028 Barcelona, Spain
Rosa Sureda
Affiliation:
Chemical Engineering Department, Universitat Politecnica de Catalunya, 08028 Barcelona, Spain
Joan de Pablo
Affiliation:
Chemical Engineering Department, Universitat Politecnica de Catalunya, 08028 Barcelona, Spain Environmental Technology Area, CTM-Centre Tecnologic, Av. Bases de Manresa 1, 08240 Manresa, Spain
Ignasi Casas
Affiliation:
Chemical Engineering Department, Universitat Politecnica de Catalunya, 08028 Barcelona, Spain
Xavier Martinez-Llado
Affiliation:
Environmental Technology Area, CTM-Centre Tecnologic, Av. Bases de Manresa 1, 08240 Manresa, Spain
Miquel Rovira
Affiliation:
Chemical Engineering Department, Universitat Politecnica de Catalunya, 08028 Barcelona, Spain Environmental Technology Area, CTM-Centre Tecnologic, Av. Bases de Manresa 1, 08240 Manresa, Spain
Aurora Martinez-Esparza
Affiliation:
ENRESA, C/ Emilio Vargas 7, 28043 Madrid, Spain
Get access

Abstract

The formation of uranyl secondary solid phases onto the spent nuclear fuel surface might influence the radionuclide concentration in solution via, among others, sorption processes. In this work, the incorporation of some radionuclides onto the uranium peroxide studtite, UO2O2·4H2O, has been tested.

The study was carried out in batch experiments where a known amount of studtite (0.05 g) was put in contact with 20 cm3 of radionuclide solution. Once equilibrium was reached, radionuclide concentrations in solution were determined by ICP-MS. The radionuclide amount attached to the solid was calculated from the mass balance. The S/V values of the experiments were also determined from BET specific solid surface area measurements.

In this work, data on sorption of caesium, strontium, and selenium as a function of pH are presented. The behaviour of caesium and strontium are similar: a relatively high amount of radionuclide is sorbed at neutral to alkaline pH while there is almost no sorption at acidic pH. On the other hand, in the case of selenium, the sorption maximum occurs at acidic pH and there is almost no sorption at alkaline pH. The different behavior of the radionuclides is related to the element speciation in solution and the surface charge of the solid. Strontium and caesium are sorbed at alkaline pH because they are positively charged in solution and the surface of the studtite is negatively charged (>O- groups) while selenium(VI) sorbs at acidic pH because the surface of the studtite is positively charged, and the predominant selenium(VI) species in solution is anionic.

These preliminary data indicate that the sorption capacity of uranyl secondary solid phases such as studtite is an important process to be considered when establishing the migration of different radionuclides released from spent nuclear fuel.

Type
Research Article
Copyright
Copyright © Materials Research Society 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1 Shoesmith, D.W., J. Nucl. Mater. 282, 1 (2000).Google Scholar
2 Wilson, C.N., Results from NNWSI Series 3 spent fuel dissolution tests. Pacific Northwest Laboratory Report PNL-7170, June 1990. Richland, Washington, USA.Google Scholar
3 Wilson, C.N., Results from NNWSI Series 2 bare fuel dissolution tests. Pacific Northwest Laboratory Report PNL-7169, September 1990. Richland, Washington, USA.Google Scholar
4 Stroess-Gascoyne, S., Johnson, L.H., Tait, J.C., McConnell, J.L., Porth, R.J. in Leaching of used CANDU fuel: results from a 19-years leach test under oxidizing conditions, edited by Gray, W.J. and Triay, I.R., (Mater. Res. Soc. Symp. Proc. 465, Pittsburgh, PA, 1997) pp. 511518.Google Scholar
5 Finn, P.A., Finch, R.J., Buck, E.C., Bates, J.K. in Corrosion mechanisms of spent fuel under oxidizing conditions, edited by McKinley, I.G. and McCombie, Ch., (Mater. Res. Soc. Symp. Proc. 506, Pittsburgh, PA, 1998) pp. 123131.Google Scholar
6 Forsyth, R.S., Werme, L.O., J. Nucl. Mater. 190, 3 (1992).Google Scholar
7 Hanson, B., McNamara, B., Buck, E.C., Friese, J., Jenson, E., Krupka, K., Arey, B., Radiochim. Acta 93, 159 (2005).Google Scholar
8 Burns, P.C., J. Nucl. Mater. 265, 218 (1999).Google Scholar
9 Hoskin, P.W.O., Burns, P.C., Mineral. Mag. 67, 689 (2003).Google Scholar
10 Douglas, M., Clark, S.B., Utsunomiya, S., Ewing, R.C., J. Nucl. Sci. Technol. Supplement 3, 504 (2002).Google Scholar
11 Burns, P.C., Li, Y., Am. Mineral. 87, 550 (2002).Google Scholar
12 Chen, F., Burns, P.C., Ewing, R.C., J. Nucl. Mater. 275, 81 (1999).Google Scholar
13 Kubatko, K.-A. Hughes, Helean, K.B., Navrotsky, A., Burns, P.C., Science 302, 1191 (2003).Google Scholar
14 Clarens, F., Pablo, J. de, Diez-Perez, I., Casas, I., Gimenez, J., Rovira, M., Environ. Sci. Technol. 38, 6656 (2004).Google Scholar
15 Douglas, M., Clark, S.B., Friese, J.I., Arey, B.W., Buck, E.C., Hanson, B.D., Environ. Sci. Technol. 39, 4117 (2005).Google Scholar
16 Rey, A., Casas, I., Gimenez, J., Quinones, J., Pablo, J. de, J. Nucl. Mater. 385, 467 (2009).Google Scholar
17 Clarens, F., Pablo, J. de, Casas, I., Gimenez, J., Rovira, M., in Surface site densities of uranium oxides: UO2, U3O8, edited by Oversby, V.M. and Werme, L.O., (Mater. Res. Soc. Symp. Proc. 807, Pittsburgh, PA, 2004) pp. 7176.Google Scholar
18 Martinez, M., Gimenez, J., Pablo, J. de, Rovira, M., Duro, L., Appl. Surf. Sci. 252, 3767 (2006).Google Scholar
19 Rovira, M., Gimenez, J., Martinez, M., Martinez-Llado, X., Pablo, J. de, Marti, V., Duro, L., J. Hazard. Mater. 150, 279 (2008).Google Scholar
20 Marmier, N., Delisee, A., Fromage, F., J. Colloid Interf. Sci. 211, 54 (1999).Google Scholar
21 Pablo, J. de, Rovira, M., Gimenez, J., Casas, I., Clarens, F., in Magnetite sorption capacity for strontium as a function of pH, edited by Lee, W.E., Roberts, J.W., Hyatt, N.C. and Grimes, R.W., (Mater. Res. Soc. Symp. Proc. 1107, Pittsburgh, PA, 2008) pp. 593598.Google Scholar
22 Sverjensky, D.A., Sahai, N., Geochim. Cosmochim. Acta 60, 3773 (1996).Google Scholar