Effect of H2O on the hydrolysis of UF6 in the gas phase

230Th-234U and 231Pa-235U radiochronometry of hydrolyzed uranium hexafluoride gas

“…The resulting solutions had a pH ≈ 2 and a high free fluoride ion concentration, optimal for keeping trace actinides in solution. Uranium hydrolysis proceeds by the generalized reaction [16]: Samples were stored in these low-pH and high fluorine concentration solutions for approximately 1.6-1.8 years.…”

Formation of Aerosol Nanoparticles by Gas-Phase Hydrolysis Reaction of Uranium Hexafluoride

“…Recently, Hu et al (2008Hu et al ( , 2009Hu et al ( , 2014 used the relativistic density function theory to computationally show that intermediate species containing a U-O-U bond were found because of several probable reactions involving UF5OH and UF6 or UF5OH and UF5OH under the condition of enriched UF6 and small amounts of H2O (i.e., small ω condition) where ω is the molar ratio of H2O to UF6. In large ω conditions, the coordination energy between UF6 and (H2O)n in UF6-nH2O (e.g., where n = 1-3) increases as water changes from single molecules to the associated dimer and trimer.…”

“…So far, these molecular dynamics modeling works (Hu et al 2008(Hu et al , 2009(Hu et al , 2014 suggested only the pathway of the UF6 hydrolysis in the gas phase, but none did for the condensed phase in which the formation of UO2F2 aerosol particles exist. The aerosol formation process and kinetics remain unknown.…”

Computational Studies of Uranium Hexafluoride Interacting with Functionalized Organics. I. Screening Intermolecular Potentials between UF6 and Small Organic Functional Groups

“…Indeed the UF 6 dimer has continued to be a topic revisited by multiple groups, both experimentally and computationally. − One potential reason depleted UF 6 remains unused is that the gas-phase UF 6 reacts with available water vapor to form uranium oxide solids. As such, the important UF 6 –H 2 O interaction has been studied in some detail. − …”