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Synroc: A Suitable Waste Form for Actinides

Published online by Cambridge University Press:  29 November 2013

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Synroc, a ceramic made from a reactive mixture of Al, Ba, Ca, Ti, and Zr oxides, is proving to be a suitable and effective medium for immobilizing nuclear wastes.

Synroc-C, a titanate-based ceramic variant, was initially developed in 1978 by Ringwood et al. for immobilizing high-level nuclear waste (HLW) from nuclear power reactor fuel reprocessing. HLW is essentially a solution of radioactive fission products, actinides, and process contaminants in ~3 mol/L nitric acid. The developers of Synroc-C aimed to immobilize radioactive waste ions by incorporating them in a ceramic. They accomplished this by mixing the HLW solution (liquid waste) with a ceramic precursor, then forming the ceramic by drying, calcining, and hot-pressing the mixture in a metal container for two hours at 1200°C/20 MPa. The result, Synroc-C, is composed of hol-landite, zirconolite, perovskite, and rutile, together with a few percent of minor phases and metal alloys. The Synroc-C precursor has the following composition (wt%): Al203(5.4); BaO(5.6); CaO(11); TiO2(71.4); and ZrO2(6.6). Since 1984, it has been prepared by hydrolyzing a mixture of Al, Ti, and Zr alkoxides with an aqueous slurry of Ba and Ca hydroxide. The abundances of the phases, and the radionuclides contained in them in dilute solid solution, are identified in Table I.

Type
Nuclear Waste Disposal
Copyright
Copyright © Materials Research Society 1994

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References

1.Ringwood, A.E., Kesson, S.E., Ware, N.G., Hibberson, W., and Major, A., Nature (London) 278 (1979) p. 219.CrossRefGoogle Scholar
2.Ringwood, A.E., Kesson, S.E., and Ware, N.G., in Scientific Basis for Nuclear Waste Management, Vol. 2, edited by Northrup, C.J.M. (Plenum Press, New York, 1980) p. 265.CrossRefGoogle Scholar
3.Coughanour, L.W., Roth, R.S., Marzullo, S., and Sennett, F.E., J. Res. Natl. Bur. Stand. 54 (1955) p. 195.Google Scholar
4.Rossell, H.J., Nature (London) 283 (1980) p. 282.CrossRefGoogle Scholar
5.Smith, K.L. and Lumpkin, G.R., in Defects and Processes in the Solid State: Geoscience Applications, The McLaren Volume, edited by Boland, J.N. and Gerald, J.D. Fitz (Elsevier, B.V., 1993) p. 401.Google Scholar
6.Vance, E.R. and Agrawal, D.K., Nucl. Chem. Waste Manage. 3 (1982) p. 229.CrossRefGoogle Scholar
7.Pepin, J.G., Vance, E.R., and McCarthy, G.J., Mater. Res. Bull. 16 (1981) p. 627.CrossRefGoogle Scholar
8.Ringwood, A.E., Kesson, S.E., Reeve, K.D., Levins, D.M., and Ramm, E.J., in Radioactive Waste Forms for the Future, edited by Lutze, W. and Ewing, R.C. (Elsevier, Amsterdam, 1988) p. 233.Google Scholar
9. Materials Characterization Center, Pacific Northwest Laboratories, Richland, WA.Google Scholar
10.Vance, E.R., Ball, C.J., Day, R.A., Smith, K.L., Blackford, M.G., Begg, B.D., and Angel, P.J., J. Alloys and Compounds, in press, 1994.Google Scholar
11.Kesson, S.E., Sinclair, W.J., and Ringwood, A.E., Nucl. Chem. Waste Manage. 4 (1983) p. 259.Google Scholar
12.Brauer, V.G. and Kristen, H., Z. anorg. allg. Chem. 456 (1979) p. 41.CrossRefGoogle Scholar
13.Keller, C. and Walter, K.H., J. Inorg. Nucl. Chem. 27 (1965) p. 1253.CrossRefGoogle Scholar
14.Matzke, Hj., Toscano, E., Walker, C.T., and Solomah, A.G., Adv. Ceram. Mater. 3 (1988) p. 285.CrossRefGoogle Scholar
15.Vance, E.R., Angel, P.J., Begg, B.D., and Day, R.A., in Scientific Basis for Nuclear Waste Management XV, edited by Ewing, R.C. (Mater. Res. Soc. Symp. Proc. Vol. 333, Materials Research Society, Pittsburgh, PA, 1994) p. 293.Google Scholar
16.Blackford, M.G., Smith, K.L., and Hart, K.P., in Scientific Basis for Nuclear Waste Management XV, edited by Sombret, C.G. (Mater. Res. Soc. Symp. Proc. 257, Pittsburgh, PA, 1992) p. 243.Google Scholar
17.Smith, K.L., Lumpkin, G.R., and Blackford, M.G., in Scientific Basis for Nuclear Waste Management XVI, edited by Interrante, C.G. and Pabalan, R.T. (Mater. Res. Soc. Symp. Proc. 294, Pittsburgh, PA, 1993) p. 129.Google Scholar
18.Seaborg, G.T., Radiochimica Acta 61 (1993) p. 115.CrossRefGoogle Scholar
19.Oversby, V.M. and Ringwood, A.E., Rad. Waste Manag. 1 (1981) p. 289.Google Scholar
20.Clinard, F.W. Jr., Hobbs, L.W., Land, C.C., Peterson, D.E., Rohr, D.L., and Roof, R.B.,J. Nucl. Mater. 105 (1982) p. 248.CrossRefGoogle Scholar
21.Clinard, F.W. Jr., Rohr, D.L., and Roof, R.B., Nucl. Instrum. Methods B 1 (1984) p. 581.CrossRefGoogle Scholar
22.Vernaz, E., Loida, A., Malow, G., Marples, J.A.C., and Matzke, Hj., Proc. 3rd European Community Conference on Radioactive Waste Management and Disposal, Luxembourg, Sept. 17-21, 1990.Google Scholar
23.Weber, W.J., Wald, J.W., and Matzke, Hj., J. Nucl. Mater. 138 (1986) p. 196.CrossRefGoogle Scholar
24.Mitamura, H., Matsumoto, S., Hart, K.P., Miyazaki, T., Vance, E.R., Tamura, Y., Togashi, S., and White, T.J., J. Amer. Ceram. Soc. 75 (1992) p. 392.CrossRefGoogle Scholar
25.Sinclair, W. and Ringwood, A.E., Geochem. Journ. 15 (1981) p. 229.CrossRefGoogle Scholar
26.Lumpkin, G.R., Ewing, R.C., Chakoumakos, B.C., Greegor, R.B., Lytle, F.W., Foltyn, E.M., Clinard, F.W. Jr., Boatner, L.A., and Abraham, M.M., J. Mater. Res. 1 (1986) p. 564.CrossRefGoogle Scholar
27.Reeve, K.D., Vance, E.R., Hart, K.P., Smith, K.L., Lumpkin, G.R., and Mercer, D.J., in Proc. International Ceramics Conference, Austceram 92, edited by Bannister, M.J. (CSIRO, Australia, 1992) p. 1014.Google Scholar
28.Mitamura, H., Matsumoto, S., Stewart, M.W.A., Tsuboi, T., Hashimoto, M., Vance, E.R., Hart, K.P., Togashi, Y., Kanazawa, H., Ball, C.J., and White, T.J., J. Amer. Ceram. Soc, in press.Google Scholar