Theses and Dissertations Collection

Several radioactive tellurium and technetium isotopes are formed during neutron induced fission of nuclear fuel, and these radionuclides are retained within the fuel matrix and by the containment provided by the fuel cladding and soluble Te2- and are some of the concern. Accumulation of low melting point telluride could result in liquid embrittlement of structural alloys. Additionally, telluride compounds can be created in the pyroprocess generating high melting point substances, affecting the performance of the electro-refiners that are used for electrolytic reduction of actinides during pyroprocessing of used nuclear fuels. Furthermore, Tc can create volatile species with the chloride and oxide salts. Thus, electrochemistry of tellurium/telluride and Tc couple were investigated in LiCl-KCl eutectic and LiCl-KCl + Li2O electrolytes at different temperatures using different electrochemical techniques such as Cyclic Voltammetry, Electrochemical Impedance Spectroscopy and Square wave voltammetry. The redox potentials, reaction intermediates and diffusivities of telluride species as function of temperature and concentration was also studied. This investigation mainly aims at finding the effect of telluride and rhenium (as technetium surrogate) species during electrochemical process.