Electronic Thesis and Dissertation Repository


Master of Science




Prof. J.C. Wren


Inadequate understanding of radiation-induced water chemistry under supercritical conditions has been identified as one of the important obstacles in the development of a supercritical water-cooled reactor. Radiolysis of supercritical water generates a variety of redox reactive species, but their persistence in supercritical water is not well understood. This thesis describes the work performed towards addressing this deficiency: (1) the development of a reliable experimental method to determine the concentrations of water radiolysis products, primarily H2, O2 and H2O2, formed under g-irradiation of sub- and supercritical water (SCW), (2) the expansion of the application ranges of the existing g-radiolysis kinetic models for liquid water and water vapour to high temperatures and pressures, and (3) the development of the first versions of the supercritical water radiolysis models based on these two models. With each model calculations were performed as a function of temperature and the computational results were analysed to identify the key reactions and reaction parameters that are important in determining the effect of temperature on the net radiolytic production of H2, O2 and H2O2. The results indicate that the model approach that has been taken is promising and worthy of further development.