Tritium Adsorption and Diffusion of 25% Silver Palladium Cathodic Membranes for Water Processing

A study was carried out to ascertain the diffusion and adsorption parameter values for tritiated water in contact with palladium-silver cathodic membranes with and without palladium black deposits. It is shown that the amount of diffused and trapped tritium, the retrodiffusion, diffusion coefficient, tritium concentrations in the alloy sublayer, and diffusion layer thickness depend on the applied cathodic potential, temperature, palladium-silver membrane thickness, palladium black deposits on the cathodic surface, and time. With a palladium black deposit on the palladium-silver, the tritium adsorption and diffusion increase. Parameter values including the activation energy are determined from electrochemical impedance spectroscopy, voltammetry, permeation experiments, and chronocoulometry.