Grant: Discovery Grants Program - Individual

The proposed research is intended to support the nuclear industry in the research areas of applied thermodynamics, high temperature materials chemistry, and aqueous chemistry at elevated temperatures. It has been established that there are material chemistry issues related to all aspects of the fuel cycle, from processing yellow cake, design of new fuel, the next generation of nuclear reactors, and waste disposal of spent fuel. While progress has been made to develop thermodynamic models for describing the behaviour of fuel in various environments (i.e., gaseous, aqueous) issues remain, and as the need to produce environmentally responsible forms of energy increases in the 21st century, it is essential that solutions to these issues be found. One of the basic tools for high temperature materials is the phase diagram and phase diagram evaluation. The proposed research will build on the primary investigator's background in applying thermodynamic phase diagram modelling to systems of interest. Previous work by the PI has modelled various metallic alloy systems known to form in burned up fuel. The quaternary system of Pd-Sn-Sb-Te and the ternary Pd-Ag-Cd are known to be important during accident scenarios: the quaternary in aerosols in the heat transfer circuit and the ternary with the control rods. As well, there are other metallic alloy systems that may be suitable liquid coolants in the next generation of reactors. In the area of proposed new fuels, uranium carbides and nitrides show potential, but are not as well understood as UO2. Further, replacing uranium with thorium (or using both together) may be of interest. Understanding how these systems behave is the first step in developing them into fuel, and is important in considering accident scenarios. A multi-year and multi-faceted approach is being proposed, continuing experimental work being performed at the University of Ontario Institute of Technology using X-ray Diffraction (XRD), Differential Thermal Analysis (DTA), and other methods. Continuing collaborations with the Canadian Nuclear Labs (Chalk River) as the PI and CNL have a long standing history. Internationally, the PI has developed links to the major research institutions in Europe (e.g., CEA, ITU, and IRSN). This has allowed for the potential to do experimental work in conjunction with these partners in areas of mutual interest. In collaboration with colleagues at UOIT, studies of proposed disposal methods for fuel are planned. The models for fuel, while developed for high temperature behaviour can be adapted to an aqueous environment (e.g., storage bays) or proposed environments for underground burial. The work also lends itself to studying corrosion in various nuclear applications. In conclusion, this work will strengthen the links between experimental work performed at UOIT (or elsewhere) and the thermodynamic and thermochemical models that can be subsequently developed.