Tritium purification via zirconium–manganese–iron alloy getter St 909 in flow processes

Abstract

A zirconium–manganese–iron alloy, St 909, was evaluated as a purifier in tritium handling, transport, and storage applications. High efficiency removal of CH4, CO, CO2, NH3, and O2 was observed at concentrations of 0.1% to 1% in helium. Gas streams at 100–5000 sccm were passed through getters operated at 600–800 °C. On-getter residence times of two seconds were required to achieve ≳99% removal of these reactive impurities. At this removal efficiency level, the individual impurity capacity of 100 g of St 909 purifier at 800 °C was 0.59, 0.28, 0.19, 0.14, and 0.12 moles of CH4, CO, CO2, O2, and NH3, respectively. Hydrogen containing gasses, CH4 and NH3 were cracked on the purifier and the resultant elemental hydrogen was released. Only 8±2 sccm of H2 were retained on 100 g of St 909 at 800 °C. These features suggest that this alloy can be employed as an efficient purifier for hydrogen isotopes in inert gas, nitrogen, or perhaps even H, D, or T streams.