THERMODYNAMICS OF NEPTUNIUM(V) FLOURIDE AND SULFATE AT ELEVATED TEMPERATURES

Rao, L. ; Tian, G. ; Xia, Y. ; Friese, J.I.

United States. Department of Energy. Yucca Mountain Project Office.

关键词: Neptunium Sulfates;    Neptunium Fluorides;    Enthalpy;    38 Radiation Chemistry, Radiochemistry, And Nuclear Chemistry;    Neptunium Complexes;   

DOI  :  10.2172/886039
RP-ID  :  NA
RP-ID  :  NA
RP-ID  :  886039

美国|英语

来源: UNT Digital Library

【 摘 要 】

Complexation of neptunium(V) with fluoride and sulfate at elevated, temperatures was studied by microcalorimetry. Thermodynamic parameters, including the equilibrium constants and enthalpy of protonation of fluoride and sulfate, and the enthalpy of complexation between Np(V) and fluoride and sulfate at 25-70 C were determined. Results show that the complexation of Np(V) with fluoride and sulfate is endothermic and that the complexation is enhanced by the increase in temperature--a threefold increase in the stability constants of NpO{sub 2}F(aq) and NpO{sub 2}SO{sub 4}{sup -} as the temperature is increased from 25 to 70 C.