Pressure-Concentration-Temperature Characterization of St 909 Getter Alloy with Hydrogen

One of the major issue related to the next generation of fusion reactors is tritium recovery and recycling from tritiated water. Among the various approaches prospected, chemical dissociation of tritiated water over active beds based on reactive alloys appears to be a promising solution. It enables, in fact, safe recovery of tritium by exploiting the relatively high equilibrium pressures, even at low concentrations and operating temperature, of selected alloys. The paper presents the results of pressure-temperature-composition measurements carried out on a Zr-Mn-Fe alloy, named St909, candidate for such a application. Equilibrium isotherms have been determined between room temperature and 400 °C for low hydrogen concentrations, and at room temperature for higher concentrations, exploring the bi-phasic region. Sieverts' law appears to be obeyed in the low concentration range, at H/A ratios of less than 0.3.