Hydrogen recovery from liquid Li with Y hot trap

Materials to compose a fusion reactor chamber are subjected to neutron irradiation. International Fusion Materials Irradiated Facility (IFMIF) will be used to analyze how neutron damage affects material durability. The material is irradiated by high-intensity neutron beam, which is generated by the D-Li stripping reaction. Tritium (T) generated by by-pass reaction needs to be recovered from liquid Li for safety. Recovery of tritium by an yttrium (Y) hot trap is one of the ways to recover T from liquid Li in IFMIF. Therefore, it is necessary to analyze the behavior of T in the liquid Li. In this study, the authors measured H₂ absorption rates under stirred conditions of liquid Li and analyzed the effect of hydrogen absorption rate of Y by elevating temperature from 250degC to 400degC to establish the way to recover T from liquid Li with the Y hot trap in IFMIF. Judging from the comparison, we considered the rate-determining step is H diffusion in Y. Mass transfer coefficients at each temperature were determined by fitting the results between calculation and experiment. (author)