SWEEP GAS CHEMISTRY EFFECT ON VAPORIZATION OF LIALO2

The equilibrium vapor pressures in the D-2-D2O-LiAlO2 system were meas ured by means of an atmosphere-controllable high temperature mass spec trometer in the temperature range 1573-1773 K. Based on the reaction, 5LiAlO(2)(s) + 2D(2)O(g) = 4LiOD(g) + LiAl5O8(s), the heat of formatio n of LiAl5O8 was evaluated to be -4553.9 kJ/mol, which is in good agre ement with the data in previous studies based on the reaction, 5LiAlO( 2)(s) = 4Li(g) + O-2(g) + LiAl5O8(s). The results of this study enable d estimation of the maximum allowable temperature with respect to lith ium transport by the sweep gas in fusion reactor blanket.