Katrina Love has a BEng (Hons) Materials Engineering degree from Sheffield Hallam University and is a chartered Engineering Technician accredited by the IOM3. She has experience working with commercial glass products from interning at GTS as a product performance assistant and has commercial awareness from working for Morgan Advanced Materials as a procurement assistant and export clerk during her industrial placement. Katrina now studies at Sheffield Hallam University as a 1st year PhD student where her research is investigating the effects of phosphate solubility and its impact on properties of radioactive waste glasses for the Hanford site. Her director of studies is Professor Paul Bingham and secondary supervisor is Dr Anthony Bell.

Katrina Love

K.L. Love 1∗, A.M.T. Bell 1, K.M. Fox 5, J.D.Vienna 2, A. Goel 3, J.S. McCloy 4 D.K. Peeler 5, D. P. Guillen 6, P.A. Bingham 1 1Materials and Engineering Research Institute, Sheffield Hallam University, City Campus, Sheffield, South Yorkshire, S1 1WB, UK 2Pacific Northwest National Laboratory, PO BOX 999, Richland, WA 99352, USA 3Department of Materials Science and Engineering, School of Engineering, Rutgers University,The State university of New Jersey, 607 Taylor Road, Piscataway, NJ 08854, USA 4 Washington State University, School of Mechanical and Materials Engineering, Washington State University, PO BOX 642920, Pullman, WA 99164 – 2920, USA 5 Savannah River National Laboratory, Savannah River Site, Alken, SC 29808, USA 6 Idaho NationalLaboratory, 1955 N. Fremont Avenue, Idaho Falls, ID 83415, USA

This research aims to understand the effects of phosphate (P2O5) on the properties, composition and structure of radioactive waste glasses relevant to clean-up of the U.S. Hanford site. P5O2 arises in the vitrified waste from the Bismuth Phosphate, REDOX and PUREX processes for plutonium extraction 1. P2O5 is poorly soluble in borosilicate glasses, with concentrations >4.5 wt % potentially leading to phase separation: this can affect melt viscosity and chemical durability 2, 3. However, P2O5 can have positive effects such as enhancing the solubilities of other species in the borosilicate glasses e.g. sulphate (SO4 2-) 4, 5. Simulant waste glasses based on Hanford compositions have been prepared, undoped and doped with P2O5. Glasses have been characterised using a number of techniques including X-ray Diffraction (XRD) to detect and identify any crystalline phases; X-ray Fluorescence (XRF) and Scanning Electron Microscopy / Energy Dispersive X-ray Spectroscopy (SEM/EDX) to provide compositional and morphological information; Raman Spectroscopy to provide structural information; and thermal analysis to understand the effects of P2O5 on the glass transition temperature Tg, glass thermal stability and crystallisation behaviour.

Keywords — Borosilicate glass, Radioactive Waste Glasses, Phase Separation, Phosphate, Sulphate

References

1.            Delegard, C. H. Jones, S. A. (2015). Chemical Disposition of Plutonium in Hanford Site Tank Wastes. doi:WTP-RPT-234 Rev. 1

2.            Schuller. S. Pinet, O, Grandjean. A, Blisson, T. (2008). Phase Separation and Crystallization of Borosilicate Glass Enriched in MoO3, P2O5, ZrO2, CaO. Journal of Non-Crystalline Solids. 354. 296-300. 10.1016/j.jnoncrysol.2007.07.041.

3.            Vienna. J. D, Piepel. G. F, Kim. D. S, Crum. J. V, Lonergan. C. E, Stanfill. B. A, Cooley. S. K and Jin. T, (2016), 2016 Update of Hanford Glass Property Models and Constraints for Use in Estimating the Glass Mass to be Produced at Hanford by Implementing Current Enhanced Glass Formulation Efforts, PNNL25835, DE-AC05-76RL01830.

4.            Vienna. J, Kim. DS, Muller I, Piepe. G, Kruger. A (2014). Toward Understanding the Effect of Low-Activity Waste Glass Composition on Sulfur Solubility. Journal of the American Ceramic Society. 97. 3135-3142. 10.1111/jace.13125.

5.            Bingham. P.A, Vaishnav. S, Forder. S, Scrimshire. A, Jaganathan. B, Rohini. J, Marra. J.C, Fox. K.M, Pierce. E, Workman. P, Vienna, J. D (2016). Modelling the sulfate capacity of simulated radioactive waste borosilicate glasses. Journal of Alloys and Compounds. 695. 10.1016/j.jallcom.2016.11.110.