Efficient HTO Reduction Using a Zr-Fe-Mn Alloy

Tritiated water production is a consequence of tritium gas handling. If tritium emission to the environment is to be minimized, then tritiated water must be processed so that the chemically bound tritium is recovered. For DT burning fusion machines, tritiated-water-processing systems are under development. These systems, however, are intended for large-scale applications and cannot be scaled down practically or economically. HTO vapour reduction to HT over hot metal getters offers a simple alternative. In such cases the metal getter selected should reduce HTO efficiently and retain negligible residual tritium inventory. HTO reduction over a Zr-Fe-Mn alloy is reported in this paper. Conversion efflciencies exceeding 90% are achievable for gas residence times above 0.7 s and alloy temperatures above 400 °C over the useful life of the alloy. HTO-to-HT conversion rates greater than 6 gmol min- i per gram of alloy can be attained for oxygen-to-alloy mole ratios from 0 up to 2.6 without a significant reduction in the reaction rate.