IN-PILE TRITIUM RELEASE FROM LITHIUM CERAMICS AND INFLUENCE OF SURFACE PROCESSES

Recent experiments at Siloe of in-pile tritium extraction from lithium ceramics have investigated the effects of temperature, material microstructure, purge gas composition, and tritium generation rate on the tritium release kinetics. The relationship between the tritium inventory and sample microstructure indicates desorption is the dominant mechanism determining tritium release for the conditions investigated. Some literature results indicate that this desorption step may be second order, others that the activation energy of desorption varies significantly with surface coverage. The changes in inventory with variations in the key parameters mentioned above were investigated to determine the applicability of these reports to in-pile tritium release. The results suggest tritium release is first order, and that the desorption activation energy is dependent on the surface coverage.