TRUEX PROCESSING OF PLUTONIUM ANALYTICAL SOLUTIONS AT ARGONNE-NATIONAL-LABORATORY

The TRUEX (TRansUranic EXtraction) solvent extraction process was deve loped at Argonne National Laboratory (ANL) for the Department of Energ y. A TRUEX demonstration completed at ANL involved the processing of a nalytical and experimental waste generated there and at the New Brunsw ick. Laboratory. A 20-stage centrifugal contactor was used to recover plutonium, americium, and uranium from the waste. Approximately 84 g o f plutonium, 18 g of uranium, and 0.2 g of americium were recovered fr om about 118 L of solution during four process runs. Alpha decontamina tion factors as high as 65,000 were attained, which was especially imp ortant because it allowed the disposal of the process raffinate as a l ow-level waste. The recovered plutonium and uranium were converted to oxide; the recovered americium solution was concentrated by evaporatio n to approximately 100 mL. The flowsheet and operational procedures we re modified to overcome process difficulties. These difficulties inclu ded the presence of complexants in the feed, solvent degradation, plut onium precipitation, and inadequate decontamination factors during sta rtup. This paper will discuss details of the experimental effort.