An Experimental Investigation on the Efficiency of HTO Reduction by Zr-Fe-Mn Getter Alloy

Tritium gas handling involves production of tritiated water which is 10000 times more hazardous than tritium gas. If tritium emission to the environment must be mini¬mized ,the need to process tritiated water and recover the chemically bound tritium ap¬pears clear. Facilities for processing tritiated water produced in fission reactors are al¬ready available while for DT fusion machine are under development. However, these fa¬cilities are intended for large scale applications and are not practical nor economic for small scale applications. HTO vapour reduction to HT over hot metal getter other than uranium offer a simple, safe and economical solution. High alloy capacity and conversion rate combined to a low tritium residual inventory in the exhausted alloy are the attractive¬ness of this method. This paper presents an experimental investigation on the efficiency of reducing HTO by a Zr-Fe-Mn alloy. The results, obtained by three independent diag-nostics (stripper set, ionization chambers and mass spectrometry) show that for gas resi-dence time above 1 s and alloy temperatures higher than 400 ?C conversion efficiency ex-ceeding 90 % are achievable. Specific conversion rates higher than 0.1 µmol/s per gram have been observed during the alloy usage while a capacity of the alloy, measured as oxygen to alloy mole ratio, above 2.6 has been measured.