PREPARATION OF U02 FOR USE IN CERAMIC FUELS PartⅡ: Continuous Precipitation of Ammonium Diuranate

摘要

A study was made of the optimum conditions for the continuous precipitation of ammonium diuranate suitable for the preparation of uranium dioxide of high sintered density.nWith uranyl nitrate solutions at a concentration of 100 g. U/1 and aqueous ammonia as reactants, ammonium diuranate precipitated at 60°C. at pH above 6.8 consistently yielded uranium dioxide which could be sintered to a density of 10.3 to 10.7 go/c.c. As the precipitation pH was increased above 6.8 the ADU became more difficult to filter. Considering both the ease of filtration of the ADU and the sinter ability of the U02» it is desirable to precipitate the ADU at a pH between 7.0 and 7.5.