Study on Sorption of Tritium on Various Material Surfaces and Its Application to Decontamination of Tritium-Sorbing Materials

Behavior of sorption of tritium on surfaces of stainless steel, aluminum and borosilicate glass has been studied using gaseous tritium with high specific activity and the newly obtained knowledge has been applied to chemical and thermal decontamination of tritium-sorbing materials. The behavior depends on a character of surface of each material. The total amount of sorbed-tritium is evaluated as a function of time of exposure to gaseous tritium. The depth-profile of sorbed-tritium is obtained by chemical etching method. From these results, practical samples of stainless steel were decontaminated. The vacuum-bakeout for 21, hours at 773 K and dissolution by dilute (5%) HCl for 2 hours enable us to obtain the decontamination factor of 200.