Glass-ceramics with internally crystallized pyrochlore for the immobilization of uranium wastes
Source abstract
Abstract
Abstract In this work, pyrochlore glass-ceramics (GCs)for uranium immobilization were synthesized by a pretreatment and melting-heat treatment method. The effects of different uranium contents on the phase composition, microstructure, uranium valence and chemical durability of the glass-ceramics were systematically investigated. With increasing uranium content, pyrochlore was always the dominant phase internally crystallized in the glass. CaAl2Si2O8, UTi2O6 and U3O8were gradually observed as minor phases in the glass-ceramics. The growth of pyrochlore enriched with uranium at different uranium contents and the overall distribution of uranium in the glass-ceramics were revealed by SEM. The uranium valence states in the samples were confirmed by XPS to be a mixture of tetravalent and hexavalent states. In addition, the GC3 sample with a high uranium waste content of 16.96 wt% exhibited a low uranium leaching rate.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Nuclear materials and radiation effects · Nuclear Materials and Properties · Geophysical Methods and Applications
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (39)
Show source-provided references
1. An introduction to nuclear waste immobilisation10.1016/S1369-7021(06)71394-3 ↗
2. Ojovan · 2014
3. The immobilization of high level radioactive wastes using ceramics and glasses10.1023/A:1018646507438 ↗
4. Nash · 2011
5. Day · 2003
6. Borosilicate and lead silicate glass matrix composites containing pyrochlore phases for nuclear waste encapsulation
7. Glass-ceramics for nuclear-waste immobilization10.1557/mrs.2017.8 ↗
8. Development of glass ceramics for the incorporation of fission products
9. Pyrochlore based glass-ceramics for the immobilization of actinide-rich nuclear wastes: from concept to reality10.1016/j.jnucmat.2012.08.035 ↗
10. HIPed tailored pyrochlore-rich glass-ceramic waste forms for the immobilization of nuclear waste
11. Development of brannerite glass‐ceramics for the immobilization of actinide‐rich radioactive wastes10.1111/jace.14975 ↗
12. Phase evolution from Ln2Ti2O7 (Ln=Y and Gd) pyrochlores to brannerites in glass with uranium incorporation10.1111/jace.15051 ↗
13. Hot isostatically pressed Y2Ti2O7 and Gd2Ti2O7 pyrochlore glass-ceramics as potential waste forms for actinide immobilization10.1016/j.jeurceramsoc.2018.11.012 ↗
14. A new method for production of glass-Ln2Ti2O7 pyrochlore (Ln = Gd, Tb, Er, Yb)10.1016/j.jeurceramsoc.2017.06.051 ↗
15. Preparation of Y2Ti2O7 pyrochlore glass-ceramics as potential waste forms for actinides: the effects of processing conditions10.1016/j.jnucmat.2017.07.004 ↗
16. Structural and spectroscopic studies on the crystallization of uranium brannerite phases in glass10.1111/jace.15750 ↗
17. Glass–ceramic nuclear waste forms obtained from SiO2–Al2O3–CaO–ZrO2–TiO2 glasses containing lanthanides (Ce, Nd, Eu, Gd, Yb) and actinides (Th): study of internal crystallization10.1016/j.jnucmat.2004.05.020 ↗
18. Crystallization of neodymium-rich phases in silicate glasses developed for nuclear waste immobilization10.1016/j.jnucmat.2006.03.014 ↗
19. Glass–ceramic nuclear waste forms obtained by crystallization of SiO2–Al2O3–CaO–ZrO2–TiO2 glasses containing lanthanides (Ce, Nd, Eu, Gd, Yb) and actinides (Th): study of the crystallization from the surface10.1016/j.jnucmat.2010.04.021 ↗
20. Zirconolite glass-ceramics for plutonium immobilization: the effects of processing redox conditions on charge compensation and durability10.1016/j.jnucmat.2017.04.015 ↗
21. Phase evolution and microstructure analysis of CaZrTi2O7 zirconolite in glass10.1016/j.ceramint.2018.01.017 ↗
22. CaZrTi2O7 zirconolite synthesis: from ceramic to glass-ceramic10.1111/ijac.13203 ↗
23. Development of sphene-based glass ceramics tailored for Canadian waste disposal conditions10.1557/PROC-6-91 ↗
24. Connection between oxygen-ion conductivity of pyrochlore fuel-cell materials and structural change with composition and temperature10.1016/S0167-2738(99)00320-3 ↗
25. Crystal chemistry and structures of uranium-doped gadolinium zirconates10.1016/j.jnucmat.2013.03.007 ↗
26. The order–disorder transition in ion-irradiated pyrochlore10.1016/S1359-6454(02)00544-X ↗
27. Spectroscopic investigations of the structural phase transition in Gd2(Ti1-yZry)2O7 pyrochlores10.1021/jp014285t ↗
28. Kinetics of pyrochlore ceramics for the disposition of plutonium[J]10.2138/am.2006.1709 ↗
29. American Society for Testing · 2010
30. EXAFS spectroscopic studies of uranium (VI) oxide precipitates10.1557/PROC-432-139 ↗
31. Strehle · 2012
32. Impact of uranyl-calcium-carbonato complexes on uranium(VI) adsorption to synthetic and natural sediments10.1021/es902194x ↗
33. Reduction of U(VI) to U(IV) on the surface of magnetite10.1016/j.gca.2005.07.003 ↗
34. Asano · 2018
35. Relationship between the structural characteristics and photoluminescent properties of LnEuTi2O7 (Ln=Gd and Y) pyrochlores10.1016/j.jlumin.2015.09.033 ↗
36. Alpha-irradiation effects in SiO210.1127/0935-1221/2008/0020-1842 ↗
37. Moghissi · 1990 · 10
38. Glass fabrication and product consistency testing of lanthanide borosilicate glass for plutonium disposition10.1016/j.jallcom.2007.02.164 ↗
39. Accelerated weathering of high-level and plutonium-bearing lanthanide borosilicate waste glasses under hydraulically unsaturated conditions10.1016/j.apgeochem.2007.03.056 ↗