TRANSPIRATION STUDIES ON THE VOLATILITIES OF PUO3(G) AND PUO2(OH)(2)(G) FROM PUO2(S) IN THE PRESENCE OF STEAM AND OXYGEN AND APPLICATION TO PLUTONIUM VOLATILITY IN MIXED-WASTE THERMAL OXIDATION PROCESSORS

摘要

Transpiration experiments have been carried out to study the volatility of PuO2(s) in the presence of oxygen and steam. Vapor pressures have been measured for PuO3(g) and PuO2(OH)(2)(g) and thermodynamic data established for them. Thus, Delta(f)H(298)(0) is determined to be -(562.8 +/- 5.0) kJ/mol for PuO3(g) and -(1,018.2 +/- 3.3) kJ/mol for PuO2(OH)(2)(g). In applying the Pu volatility data to a pilot scale mixed waste (containing both radioactive and hazardous constituents) incinerator with primary and secondary combustion chambers, it is found that Pu volatilization makes a negligible contribution to air emissions if the temperature in the secondary combustor is maintained at less than 1600 K. Chlorine-and fluorine-induced volatilities of plutonium are not considered in this analysis. (C) 1997 Elsevier Science B.V. [References: 9]