Results of tritium experiments on ceramic electrolysis cells and palladium diffusers for application to fusion reactor fuel cleanup systems

The authors present results of tritium tests at the Tritium Systems Test Assembly which have demonstrated that ceramic electrolysis cells and palladium alloy diffusers developed in Japan are possible components for a fusion reactor fuel cleanup system. Both components have been successfully operated with tritium for over a year. A failure of the first electrolysis cell was most likely the result of an overvoltage on the ceramic. A simple circuit was developed to eliminate this mode of failure. The palladium diffuser tubes exhibited some degradation of mechanical properties as a result of the build up of helium from the tritium decay, after 450 days of operation with tritium, however the effects were not significant enough to affect the performance. New models of the diffuser and electrolysis cell, providing higher flow rates and a more tritium compatible designs are currently being tested with tritium