Tritium oxidation test by platinum-alumina catalyst under moisture and hydrocarbons atmosphere

Abstract

To design a detritiation system (DS) applicable to a fire event, it is important to investigate influence of moisture and hydrocarbons produced by combustion of cables in fire on tritium oxidation efficiency of a catalytic reactor. In our experiments, when we assumed that tritium release in a simulated room in the following scenarios as fire situation, (I) tritium only; (II) tritium and excess moisture; (III) tritium and excess hydrocarbons, we conducted demonstration test of tritium oxidation using by DS consist of a catalytic reactor packed with platinum-alumina catalyst and a dryer with molecular sieves. We investigated the detritiation behavior and determined the volume of catalyst to satisfy requirement of tritium oxidation efficiency of a catalytic reactor packed with the catalyst. The tritium concentration theoretically decreased by DS since the tritium oxidation efficiency kept high under the conditions of three scenarios. Our results showed that the concentration of hydrogen in air and temperature of catalyst had an influence on the tritium oxidation efficiency of the catalytic reactor. We determined the worst scenario for tritium oxidation and evaluated the amount of catalyst to meet the requirement of the tritium oxidation efficiency.