Kinetics of gas-phase conversion of U3O8 into water-soluble compounds in nitrating atmosphere at 25–30°С

Abstract

The kinetics of the gas-phase conversion of U₃O₈ in NO_x–H₂O (vapor)–air and HNO₃ (vapor)–H₂O (vapor)–air atmospheres was fitted by the Kazeev–Kolmogorov–Erofeev equation. The following parameters n and K were obtained: for experiments in NO_x–H₂O (vapor)–air atmosphere, n = 0.2 ± 0.1 and K = 0.2 ± 0.2 h^–1; for experiments in HNO₃ (vapor)–H₂O (vapor)–air atmosphere, n = 0.3 ± 0.2 and K = 0.03 ± 0.02 h^–1 (confidence probability p = 0.95). For the U₃O₈ conversion in both media, n < 0.5, which suggests the diffusion control of the U₃O₈ conversion under the action of both HNO₃ and NO_x.