Volatilization of urania under strongly oxidizing conditions

Abstract Vapor pressures are presented for UO 3 (g) over U 3 O 8− x in air by the transpiration technique. Measurements are also presented for UO 3 over the two-phase region, UO 2.24 –UO 2.60. Measurements made in steam-oxygen led to establishment of the homogeneous equilibrium UO 3 (g) + H 2 O(g) = UO 2 (OH) 2 (g). Some thermochemical values are presented. A method is shown for computing UO 3 and UO 2 (OH) 2 pressure for any temperature, steam concentration, and oxygen potential. Total volatilities and mass loss rates have been computed for some potential loss of pool coolant scenarios.