Electrochemical Sensors and Techniques for Redox Potential and Tritium Transport in a Neutron-Irradiated Molten Flibe Salt Loop

A consortium of the Massachusetts Institute of Technology, North Carolina State University, the University of California at Berkeley (UCB) and Oak Ridge National Laboratory have initiated a project to build a neutron-irradiated molten-salt forced-circulation loop at the MIT reactor. The loop will use FLiBe (Li2BeF4) salt and will duplicate thermal-hydraulics, chemical, and neutronics conditions in a salt reactor.

The SALT Lab at UCB is responsible for the design and application of electrochemical sensors and techniques for redox measurement and tritium transport within the loop. The proposed experiments will investigate redox measurements and control in the loop, tritium retention and diffusion in graphite, and tritium transport in the salt. Redox measurements and control studies will be performed to quantify the corrosive effect of neutron activation reactions and the effect of redox control agents in the loop. Tritium studies are being developed to quantify tritium uptake capacity in graphite, identify tritium desorption mechanisms, and measure tritium solubility, diffusivity, and speciation in the melt. To support these experiments, a variety of electrochemical probes are under development at UCB, including different size, shape, and material of the electrodes.

This talk will present the electrochemical probes under development and discuss the experiments that will be tested off-loop in the Be-gloveboxes of the SALT lab and then implemented in the loop.