Crystal chemistry and phase manipulation in Synroc

No Thumbnail Available
Journal Title
Journal ISSN
Volume Title
Trans Tech Publications Ltd
Synroc is a multi-phase ceramic designed for geological immobilisation of radioactive waste produced by reprocessing nuclear fuel from power reactors [1]. The main crystalline phases are hollandite, perovskite, zirconolite, and reduced titanium oxide. The compositions of these phases and the nuclides they can incorporate in solid solution are shown in Table 1. Table 1. Principal Phases comprising Synroc Phase Nominal Composition Waste nuclides incorporated Estimated wt%* [2] Hollandite Ba1.14(Al, Tr3+)2.28Ti6O16 Cs, Sr, Rb 25 Perovskite CaTio3 Sr, RE, An 20 Zirconolite CaZrTi2O7 RE, An 20 Titanium Oxide TinO2n-1 - 35 *No HLW present RE = rare earths, An = actinides. The main (Synroc-C) formulation is designed for Purex reprocessing waste and the standard composition is wt%: Al2O3(4.3); BaO(4.4); CaO(8.8); ZrO2(5.6); TiO2(57.9); waste oxides (20). The loading of high-level waste (HLW) oxides can be varied if desired, but probably cannot exceed a value of 30-35% [2]. Several variants of this composition have been formulated at the laboratory scale, with Synroc-D, E and F being directed towards Savannah River (U.S.A.) military waste, encapsulation of high-level nuclear reprocessing waste and unreprocessed spent fuel respectively. © 1991 Trans Tech Publications Ltd.
Proceedings of the 2nd International Ceramic Conference (AUSTCERAM '90), Perth, Western Australia, August 1990
Crystals, Chemistry, Synthetic rocks, Radioactive wastes, Synroc process, Phase transformations
Vance, E. R., Moricca, S., Thorogood, G. J., & Lumpkin, G. R. (1991). Crystal chemistry and phase manipulation in Synroc. Paper presented at the 2nd International Ceramic Conference (AUSTCERAM’90), Perth, Western Australia, August 1990. In Key Engineering Materials, 53-55, 717-721. doi:10.4028/