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

Elucidating the Composition and Structure of Uranium Oxide Powders Produced via NO2 Voloxidation

“…The direct U 3 O 8 reaction with NO 2 is well documented in the literature, with a consensus that the reaction produces UO 3 under dry conditions. ,,,, If water vapor is also present, then U 3 O 8 has been shown to form soluble uranyl compounds that have been suggested to be uranyl nitrate or uranyl hydroxynitrate . The specific reaction of UO 3 under NO 2 (g) is not well documented.…”

“…Some reports indicate that dry nitration with NO 2 (g) terminates at the formation of UO 3 and that formation of uranyl nitrate is not reported. , Alternatively, another study indicates that an NO 2 reaction with U 3 O 8 can produce NO­(UO 2 )­(NO 3 ) 3 , although the kinetics of the reaction are on the order of weeks or months. Additional information suggests that in the presence of water vapor, NO 2 (g) reacts with U 3 O 8 to form soluble uranyl nitrate compounds . These discrepancies in reaction mechanisms lead to questions about the potential for formation of nitrate compounds and the conditions and time scales required to form uranyl nitrates in NO 2 (g) atmospheres.…”

“… 5 , 9 , 10 , 13 , 15 If water vapor is also present, then U 3 O 8 has been shown to form soluble uranyl compounds that have been suggested to be uranyl nitrate or uranyl hydroxynitrate. 16 The specific reaction of UO 3 under NO 2 (g) is not well documented. One report uses thermogravimetric data to show that UO 3 reacts with NO 2 (g), and the authors suggest the product may be a uranyl nitrate phase.…”

“…Additional information suggests that in the presence of water vapor, NO 2 (g) reacts with U 3 O 8 to form soluble uranyl nitrate compounds. 16 These discrepancies in reaction mechanisms lead to questions about the potential for formation of nitrate compounds and the conditions and time scales required to form uranyl nitrates in NO 2 (g) atmospheres.…”