Tritium release from ceramic breeder materials

Lithium aluminate is an attractive material (in terms of its chemical, mechanical, and irradiation properties) for breeding tritium in fusion reactors; however, its tritium release characteristics are not as good as those of other candidate materials. To investigate whether tritium release from lithium aluminate can be improved, tritium release has been studied from irradiated samples of lithium aluminate, lithium aluminate doped with magnesium, and lithium aluminate with a surface deposit of platinum. The release was studied using the Temperature Programmed Desorption (TPD) method. Both the platinum coating and magnesium doping were found to improve the tritium release characteristics as determined by TPD. Tritium release shifted to lower activation energies for the altered materials. In addition, information gained from the TPD experiments on the pure material were used to improve a tritium release model. The new model containing no adjustable parameters was used to successfully model in-pile tritium release from LiA1O{sub 2}.