The Construction and Validation of Rotating Electrodes in Molten Salts for the Measurement of Hydrodynamic Properties and Corrosion

Abstract

Among electrochemical techniques, rotating electrodes are particularly useful for molten salt research due to their ability to precisely control the rate of mass transfer via the rotational rate of the electrode. Rotating electrodes create well-developed flow patterns with established mathematical relations for certain geometries. From these relations, it is possible to measure viscosities, diffusion coefficients, and other properties of molten salts relevant to nuclear material processing and molten salt reactors (MSR). Rotating electrodes have the potential to simulate the hydrodynamic conditions in a molten salt reactor and provide in situ feedback during corrosion testing. Additionally, rotating electrodes require significantly less material for corrosion testing than flow loops, offering a low-cost means to screen material and salt compositions for more expensive and larger flow loop experiments. Although rotating electrodes have been used extensively in aqueous solutions, there have been very few attempts to apply them to molten salts. The high efficiency electrochemical test (HEET) facility at Brigham Young University (BYU) has been designed and constructed specifically for rotating electrode tests in molten salts. The constructed cells will be presented along with initial test data to benchmark and validate the hydrodynamic relations in molten salts by comparing them to aqueous hydrodynamic relations for similar rotating electrode geometries.