Sinterable uranium dioxide prodn - by contacting uranyl fluoride with steam then reducing the obtd triuranium octoxide

摘要

Sinterable UO2 is prepd. by fluidising a bed of UO2F2 solids at 730 degrees C (pref. 730-780 degrees C) while countercurrently contacting the solids with excess steam to convert UO2F2 to U3O8 and then fluidising the U3O8 at 500 degrees C while counter-currently contacting the U2O8 with excess H2 in the presence of steam. The obtd. UO2 is of low F circled negative concn. Pref. UO2F2 solids are produced by introducing UF6 and steam countercurrently into a fluid bed of UO2F2 seed particles at 658-780 degrees C, pref. 658-680 degrees C. U3O8 is reduced in a second reactor at pref. 450-500 degrees C using H2:steam ratio of 2-15:1 a and ratio H2:U3o8 of 3-2.5:1.