Experimental study of tritium recovery from liquid lithium by yttrium

The recovery of hydrogen in liquid Li by Y was investigated in the range 573–773 K. To recover tritium down to 1 wppm from Li, it is necessary to absorb tritium in Li into the Y hydride around at 523 K, if Y is in a hydride phase. However, it was found that limiting the use of the Y bed until its α phase relieves the temperature restriction. The hydrogen recovery rate was determined comparatively among the static Li–H2, Y–H2 and Li–Y–H2 systems. Although the hydrogen absorbing rate of Li–Y–H2 was comparable to that of Y–H2 at 673 K, it decreased at temperatures lower than 623 K due to reaction resistance at the Y surface. Relation between the surface effect and temperature was discussed.