Abstract
This work aims to assess the solubility and the surface reactivity of crystallized thorium at pH 3.0 in presence of three types of solids: synthesized powder at 1300°C, crushed kernel, and intact kernel. In this study, the kernel is composed by the core solid from high temperature reactors (HTR) sphere particles. The originality of this work consisted in following in a sequential order the kinetic of dissolution, the surface reactivity in presence of isotope tracer 229Th, and its desorption process. Long time experiments (634 days) allowed to get deeper understanding on the behavior of the surface reactivity in contact with the solution. Solubility values are ranging from 0.3×10−7 mol·L−1 to 3×10−7 mol·L−1 with a dissolution rate of 10−6–10−4 g·m−2 day−1. PHREEQC modeling showed that crystallized ThO2(cr, 20 nm) phase controls the equilibrium in solution. Isotope exchange between 229Th and 232Th indicated that well-crystallized phase exist as an inert surface regarding to the absence of exchange between surface solid and solution.
Acknowledgment
The research leading to these results has received funding from the European Union’s European Atomic Energy Community’s (Euratom) Seventh Framework Programme FP7-Fission-2010 under grant agreement n° 269688 (SKIN project). We acknowledge N. Stephant for SEM measurements from the “Institut des Matériaux Jean Rouxel” laboratory (Nantes, France) and IPNO laboratory (Orsay, France) for the BET measurements.
References
1. Ammerich, M., Frot, P., Gambini, D.-J., Gauron, C., Moureaux, P., Herbelet, G., Lahaye, T., Pihet, P., Rannou, A., Vial, E.: Report INIS-FR–15-0198 (2013).Search in Google Scholar
2. Soppera, N., Bossant, M., Dupont, E.: JANIS 4: An improved version of the NEA Java-based nuclear data information system. Nuclear Data Sheets 120, 294 (2014).10.1063/1.1945070Search in Google Scholar
3. Barthel, F. H., Tulsidas, H.: World Thorium occurences, resources and deposits. IAEA International Symposium on Uranium Raw Material for Nuclear Energy (URAM 2014) (2014).Search in Google Scholar
4. Wna: Thorium. number 01215741 (2014).Search in Google Scholar
5. Alliot, C., Grambow, B., Landesman, C.: Leaching behaviour of unirradiated high temperature reactor (HTR) UO2-ThO2 mixed oxides fuel particles. J. Nucl. Mater. 346, 32 (2005).10.1016/j.jnucmat.2005.05.018Search in Google Scholar
6. Hubert, S., Barthelet, K., Fourest, B., Lagarde, G., Dacheux, N., Baglan, N.: Influence of the precursor and the calcination temperature on the dissolution of thorium dioxide. J. Nucl. Mater. 297, 206 (2001).10.1016/S0022-3115(01)00604-3Search in Google Scholar
7. Heisbourg, G., Hubert, S., Dacheux, N., Ritt, J.: The kinetics of dissolution of Th1-xUxO2 solid solutions in nitric media. J. Nucl. Mater. 321, 141 (2003).10.1016/S0022-3115(03)00213-7Search in Google Scholar
8. Rai, D., Moore, D. A., Oakes, C. S., Yui, M.: Thermodynamic model for the solubility of thorium dioxide in the Na+-Cl--OH--H2O system at 23°C and 90°C. Radiochim. Acta 88, 297 (2000).10.1524/ract.2000.88.5.297Search in Google Scholar
9. Altmaier, M., Neck, V., Fanghanel, T.: Solubility and colloid formation of Th(IV) in concentrated NaCl and MgCl2 solution. Radiochim. Acta 92, 537 (2004).10.1524/ract.92.9.537.54983Search in Google Scholar
10. Rothe, J., Denecke, M. A., Neck, V., Müller, R., Kim, J. I.: XAFS investigation of the structure of aqueous thorium (IV) species, colloids, and solid thorium (IV) oxide/hydroxide. Inorg. Chem. 41, 249 (2002).10.1021/ic010579hSearch in Google Scholar PubMed
11. Landesman, C., Delaunay, S., Grambow, B.: Leaching behavior of unirradiated high temperature reactor (HTR) UO2-ThO2 mixed oxides fuel particles. MRS Proc. 807, 95 (2003).10.1557/PROC-807-95Search in Google Scholar
12. Felmy, A. R., Rai, D., Mason, M. J.: The solubility of hydrous thorium (IV) oxide in chloride media: Development of an aqueous ion-interaction model. Radiochim. Acta 55, 177 (1991).10.1524/ract.1991.55.4.177Search in Google Scholar
13. Moon, H.-C.: Equilibrium ultrafiltration of hydrolized thorium (IV) solutions. Bull. Korean Chem. Soc. 10, 270 (1989).Search in Google Scholar
14. Nabivanets, B. I., Kudritskaya, L. N.: Hydroxo-compleses of thorium (IV). Ukr. Khim. Zh. 30, 891 (1964).Search in Google Scholar
15. Rai, D., Felmy, A. R., Sterner, S. M., Moore, D. A., Mason, M. J., Novak, C. F.: The solubility of Th (IV) and U (IV) hydrous oxides in concentrated NaCl and MgCl2 solutions. Radiochim. Acta 79, 239 (1997).10.1524/ract.1997.79.4.239Search in Google Scholar
16. Baes Jr, C. F., Meyer, N. J., Roberts, C. E.: The hydrolysis of Thorium (IV) at 0 and 95°C. Inorg. Chem. 4, 518 (1965).10.1021/ic50026a017Search in Google Scholar
17. Bundschuh, T., Knopp, R., Müller, R., Kim, J. I., Neck, V., Fanghänel, T.: Application of LIBD to the determination of the solubility product of thorium(IV)-colloids. Radiochim. Acta 88, 625 (2000).10.1524/ract.2000.88.9-11.625Search in Google Scholar
18. Dzimitrowicz, D. J., Wiseman, P. J., Cherns, D.: An electron microscope study of hydrous thorium dioxide ThO2·nH2O. J. Colloid Interf. Sci. 103, 170 (1985).10.1016/0021-9797(85)90089-XSearch in Google Scholar
19. Rousseau, G., Fattahi, M., Grambow, B., Boucher, F., Ouvrard, G.: Coprecipitation of thorium with UO2. Radiochim. Acta 90, 523 (2002).10.1524/ract.2002.90.9-11_2002.523Search in Google Scholar
20. Rousseau, G., Fattahi, M., Grambow, B., Boucher, F., Ouvrard, G.: Coprecipitation of thorium and lanthanum with UO2+x (s) as host phase. Radiochim. Acta 94, 517 (2006).10.1524/ract.2006.94.9-11.517Search in Google Scholar
21. Jernström, J., Vuorinen, U., Hakanen, M.: Solubility of thorium in 0.1 M NaCl solution and in saline and fresh anoxic reference groundwater. POSIVA report 2002-06 (2002).Search in Google Scholar
22. Neck, V., Muller, R., Bouby, M., Altmaier, M., Rothe, J., Denecke, M. A., Kim, J. I.: Solubility of amorphous Th(IV) hydroxide – application of LIBD to determine the solubility product and EXAFS for aqueous speciation. Radiochim. Acta 90, 485 (2002).10.1524/ract.2002.90.9-11_2002.485Search in Google Scholar
23. Östhols, E.: The solubility of microcrystalline ThO2 in phosphate media. Radiochim. Acta 68, 185 (1995).10.1524/ract.1995.68.3.185Search in Google Scholar
24. Östhols, E., Bruno, J., Grenthe, I.: On the influence of carbonate on mineral dissolution. III The solubility of microcrystalline ThO2 in CO2-H2O media. Geochim. Cosmochim. Ac. 58, 613 (1994).10.1016/0016-7037(94)90492-8Search in Google Scholar
25. Wierczinski, B., Helfer, S., Ochs, M., Skarnemark, G.: Solubility measurements and sorption studies of thorium in cement pore water. J. Alloy. Compd 271, 272 (1998).10.1016/S0925-8388(98)00069-3Search in Google Scholar
26. Altmaier, M., Neck, V., Müller, R., Fanghänel, T.: Solubility of ThO2·xH2O (am) in carbonate solution and the formation of ternary Th (IV) hydroxide-carbonate complexes. Radiochim. Acta 93, 83 (2005).10.1524/ract.93.2.83.59420Search in Google Scholar
27. Bitea, C., Müller, R., Neck, V., Walther, C., Kim, J. I.: Study of the generation and stability of thorium (IV) colloids by LIBD combined with ultrafiltration. Colloids Surf. A Physicochem. Eng. Asp. 217, 63 (2003).10.1016/S0927-7757(02)00559-9Search in Google Scholar
28. Neck, V., Kim, J. I.: Solubility and hydrolysis of tetravalent actinides. Radiochim. Acta 89, 1 (2001).10.1524/ract.2001.89.1.001Search in Google Scholar
29. Myllykylä, E., Lavonen, T., Stennett, M., Corkhill, C., Ollila, K., Hyatt, N.: Solution composition and particle size effects on the dissolution and solubility of a ThO2 microstructural analogue for UO2 matrix of nuclear fuel. Radiochim. Acta 103, 565 (2015).10.1515/ract-2014-2271Search in Google Scholar
30. Vandenborre, J., Abdelouas, A., Grambow, B.: Discrepancies in thorium oxide solubility values: a new experimental approach to improve understanding of oxide surface at solid/solution interface. Radiochim. Acta 96, 515 (2008).10.1524/ract.2008.1531Search in Google Scholar
31. Vandenborre, J., Grambow, B., Abdelouas, A.: Discrepancies in thorium oxide solubility values: study of attachment/detachment processes at the solid/solution interface. Inorg. Chem. 49, 8736 (2010).10.1021/ic100756fSearch in Google Scholar
32. Oecd/Nea: Chemical Thermodynamics of Thorium, OECD Nuclear Energy Agency Data Bank, Eds., OECD Publications, Paris, France (2008).Search in Google Scholar
33. Rand, M., Fuger, J., Grenthe, I., Neck, V., Rai, D.: Chemical thermodynamics of thorium, Issy-les-Moulineaux (2009).Search in Google Scholar
34. Müller, A.: Establishment of the technology to manufacture uranium dioxide kernels for PBMR fuel. Proceedings HTR2006: 3rd International Topical Meeting on High Temperature Reactor Technology B00000070 (2006).Search in Google Scholar
35. Goldstein, S. J., Murrell, M. T., Williams, R. W.: Half-life of 229Th. Phys. Rev. C 40, 2793 (1989).10.1103/PhysRevC.40.2793Search in Google Scholar
36. Petricek, V., Dusek, M., Palatinus, L.: The crystallographic computing system. (2006).Search in Google Scholar
37. Cheary, R. W., Coelho, A. A.: A fundamental parameters approach to X-ray line-profile fitting. J. Appl. Crystallogr. 25, 109 (1992).10.1107/S0021889891010804Search in Google Scholar
38. Cheary, R. W., Coelho, A. A.: Axial divergence in a conventional X-ray powder diffractometer. I. Theoretical foundations. J. Appl. Crystallogr. 31, 851 (1998).10.1107/S0021889898006876Search in Google Scholar
39. Cheary, R. W., Coelho, A. A.: Axial divergence in a conventional X-ray powder diffractometer. II. Realization and evaluation in a fundamental-parameter profile fitting procedure. J. Appl. Crystallogr. 31, 862 (1998).10.1107/S0021889898006888Search in Google Scholar
40. Cohen, I., Berman, R. M.: A metallographic and X-ray study of the limits of oxygen solubility in the UO2-ThO2 system. J. Nucl. Mater. 18, 77 (1966).10.1016/0022-3115(66)90073-0Search in Google Scholar
41. Parkhurst, D. L., Appelo, C. A. J.: PHREEQC, a computer program for speciation, batch-reaction, one dimensional transport, and inverse geochemical calculations (2006).Search in Google Scholar
42. Duro, L., Grivé, M., Giffaut, E.: ThermoChimie, the ANDRA Thermodynamic Database. MRS Proc. 1475, imrc11 (2012).10.1557/opl.2012.637Search in Google Scholar
43. Rai, D., Yui, M., Moore, D. A.: Solubility and solubility product at 22°C of UO2(c) precipitated from aqueous U(IV) solutions. J. Solution Chem. 32, 1 (2003).10.1023/A:1022671530250Search in Google Scholar
44. Neck, V., Altmaier, M., Muller, R., Bauer, G., Fanghanel, T., Kim, J. I.: Solubility of crystalline thorium dioxide. Radiochim. Acta 91, 253 (1991).10.1524/ract.91.5.253.20306Search in Google Scholar
45. Godinho, J. R. A., Piazolo, S., Evins, L. Z.: Effect of surface orientation on dissolution rates and topography of CaF2. Geochim. Cosmochim. Ac. 86, 392 (2012).10.1016/j.gca.2012.02.032Search in Google Scholar
46. Skomurski, F. N., Shuller, L. C., Ewing, R. C. and Becker, U.: Corrosion of UO2 and ThO2: A quantum-mechanical investigation. J. Nucl. Mater. 375, 290 (2008).10.1016/j.jnucmat.2007.12.007Search in Google Scholar
©2017 Walter de Gruyter GmbH, Berlin/Boston
