The dissociation of tritiated water and the recovery of tritium is an important issue for the future thermonuclear fusion device.

Various solutions have been prospected including chemical dissociation on active beds.

The results of H2O sorption tests performed on different possible candidate alloys, by means of vacuum microbalance tecnique at a pressure of some hundreds Pa and at temperatures ranging from 300 to 400°C, are presented. From these tests a ternary Zr-Mn-Fe alloy appears to have promising features, combining good dissociation characteristics for H2O with low hydrogen pick-up.

The basic properties of this material are discussed, including structural aspects and sorption characteristics vs. other gases.