Oxidation reaction kinetics of pentavalent uranium by xenon trioxide

Using the method of kinetic luminescence spectroscopy, oxidation reaction of pentavalent uranium with xenon trioxide in 0.1 mol/l HClO4 at 298 K in the presence of uranyl ions is investigated. The reaction rate constant of aqua-ion interaction with XeO3 molecules is found: k1=(6.53+-0.09)x102 molsup(-1) x l x ssuo(-1). Decrease in uranium (5) oxidation reaction rate with an increase in UOsub(2)sup(2+) ion concentration in solution is detected. It is shown, that the phenomenon takes place due to the formation of complexes UO2+, UOsub(2)sup(2+), which react with XeO3 much slower (k2 < 2.9x102 mol sup(-1) x s xsup(-1)). The conclusion is not the limiting stage in the process of uranium (4) oxidation by xenon trioxide