Chemical equilibrium studies of tritium--lithium and tritium--lithium alloy systems

In deuterium-tritium fusion reactors currently under design, the production of tritium is accomplished by utilizing a lithium-bearing blanket. Lithium metal is presently the leading candidate for the blanket material, although molten Li2BeF4, solid Li--Al (50-50 at. percent) alloy and other lithium-containing materials are distinct possibilities. This paper summarizes progress of ongoing studies of the thermodynamics of some of these lithium containing systems. The individual solubilities of hydrogen, deuterium, and tritium in lithium as a function of temperature (700 to 10000C) and pressure are presented. Recent work with the solid alloy Li--Al (50-50 at. percent) has shown that the tritium solubility between 400 and 6000C is low. When the tritium pressure was between 0.14 and 0.52 torr, the Li--Al samples contained only 1 to 4 ppm tritium