Thermodynamics of Li2O and other breeders for fusion reactors

Abstract Thermodynamic calculations have been made to compare the thermochemical performance of three candidates for tritium breeder blanket materials Li 2 O, LiAlO 2 , and Li 4 SiO 4 . These calculations were done for the temperature range of 900–1300 K and the oxygen activity range of 10 −25 to 10 −5 . In general, LiAlO 2 offers advantages over Li 2 O, and Li 2 O, in turn, appears better than Li 4 SiO 4 . The protium purge technique of enhancing tritium release is explored for the LiAlO 2 system. Oxygen activity is an influential variable in these systems and must be considered in executing and interpreting measurements on rates of tritium release, the chemical form of the released tritium, diffusion of tritiated species and their identities, retention of tritium in the condensed phase, and solubility of hydrogen isotope gases. Surface adsorption is seen as a potentially significant contributor to tritium inventory.