= (2a 
products from the organic stream and at the same time refluxes 
some uranium and plutonium to the extraction section of the tower. 
The organic stream from the compound extraction-scrub tower 
passes to a partitioning tower in which uranium and plutonium are 
separated quantitatively. This is accomplished by reducing the 
plutonium to a non-extractable valence state using a selective 
reducing agent for plutonium dissolved in an aqueous phase. 
Plutonium nitrate is extracted from the organic phase to the 
aqueous phase, leaving uranium in the organic phase. Uranium 
bearing organic phase then passes to a stripping tower where the 
uranium is extracted by water from the organic stream. Several 
additional cycles of extraction may be required to reduce the 
fission product activity carried with both the uranium and plutonium 
streams to acceptable tolerance levels. Fission products are removed 
by factors greater than one part per million parts of uranium or 
plutonium; very high recovery of uranium and plutonium are obtained. 
4. Fission product bearing waste streams are produced from the first 
column in each solvent extraction cycle, but the first cycle extraction 
tower raffinates contain over 99.9% of the fission products. This 
stream may be combined with others to constitute the radioactive 
wastes from a chemical reprocessing plant. 
5. Radioactive wastes from other sources contribute to the overall waste 
picture. Vessel off-gases, and particularly dissolvers, may be scrubbed 
131 and entrained radioactive 
to remove fission product gases such as I 
spray and solids. The organic solvent used in the process is re- 
eyeled for reuse only after a cleaning operation which produces 
slightly active wastes. 
DECLASSIFIED 
