Accommodation of Uranium into the Garnet Structure
Journal
MRS Proceedings
Journal Volume
713
ISSN
0272-9172
1946-4274
Date Issued
2002
Author(s)
Yudintsev, Sergey V.
Lapina, Marya I.
Ptashkin, Alexander G.
Ioudintseva, Tatiana S.
Wang, Lumin M.
Ewing, Rodney C.
Abstract
One promising host for actinide wastes is garnet-type phases of general formula AVIII3BVI2[XO4]3. To determine the isomorphic capacity of garnet for uranium, CaO - Fe2O3 - Al2O3 - SiO2 - ZrO2 - Gd2O3 - UO2 system was studied. Experiments were performed in air medium at 1400 - 1500°C and 1 atm. The garnets have high capacity for Gd and Zr, while incorporation of U was found to be greatly dependent on the phase composition. Uranium content decreased from 18 wt.% in Ca-Zr-Fe garnet to 0.6 wt.% in Si-doped phases. Heavy ion irradiation (1.0 MeV Kr++) experiments were carried out for a garnet with maximal U content, (Ca2,7U0,3) VIII(Zr1,7Fe0,3) VI(Al1,1Fe1,9)IV O12. Amorphization dose of the phase was equal to 1.63×1014 ions/cm2 that is close to the other actinide hosts, such as pyrochlore Gd2Ti2O7.
Subjects
Actinides
Amorphization
Dosimetry
Heavy ions
Ion bombardment
Phase composition
Radioactive wastes
Thermal effects
Uranium
Isomorphic capacity
Tetravalent ions
Garnets
Publisher
Springer Science and Business Media LLC
Type
journal article