Neutron Activation, Gamma Spectrometry and Tritium Measurements on Italian Lithium Aluminate and Zirconate, as Selection Means of Candidate Breeders for Fusion Reactors

Measurements of impurities and tritium releasing characteristics of Lithium Aluminate and Zirconate, prepared by ENEA in the frame of the European Program on Fusion Technology, have been performed, respectively, by neutron activation analysis (NAA) and “out of pile” annealing. The resulting tritium removing rate from the ceramics was interpreted in terms of surface desorption kinetics. With reference purge gas (He + 0.1% H₂), the predominant form of tritium, released by lithium aluminate is HT/T₂, HTO/T₂O by lithium zirconate. The latter was found to have a better performance in tritium release than aluminate. The presence of moisture was found to catalyse the tritium release at lower temperatures.