Special thermodynamic features in the $\rm Li$–$\rm LiD$ system at phase equilibrium

The $\rm Li$–$\rm LiD$ system is considered under conditions of liquid–vapor phase equilibrium. The liquid is a binary infinitely dilute solution of lithium deuteride in lithium, and the coexisting vapor phase is a multi-component chemically reacting ideal mixture of gas components. The previously unknown existence of azeotropy in the $\rm Li$–$\rm LiD$ system is revealed with the concentration of components expressed in atomic fractions of deuterium and lithium in both phases, and the temperature and concentration limits of the azeotropic zone are found. Note is made of the practical importance of the thus obtained regularities.