Oxidn. of plutonium(IV) nitrate soln. - to obtain complex ammonium carbonate cpd. contg. hexavalent plutonium and possibly also uranium

摘要

An initial soln. contains HNO3, Pu(NO3)4, and possibly also UO2(NO3)2, and is fed into an evaporator for concn. The conc. soln. is next fed down a reaction column in which the temp. in the upper part of the column is 120-140 deg.C, and the temp. in the lower part is 140-170 deg.C. The molten mass obtd. from the base of the column is diluted with HNO3, and is directly fed to a known pptn. process for the prodn. of the cpd. (NH4)4 U/PuO2 (CO3)3 in which the Pu is in the hexavalent state. The vapour leaving the column is pref. condensed to obtain HNO3 which can be temporarily stored and/or used as an oxidant in different zones of the column. Simpler control and maintenance as compared with prior art process.