The separated U and Pu streams emanating from the partitioning cycle still contain some fission product impurities. In order to complete decontamina­tion of products, complementary purification cycles are required based on the same principles of the extraction chemistry described above. These two independent purification cycles are represented in Fig. 6.3. The primary contaminants in the Pu stream are typically Ru, Rh, and in some cases Np (depending on the operation and design of the early partitioning step), and the Pu purification cycle allows additional decontamination factors to be achieved with respect to these fission products. The uranium purification cycle is used primarily to enhance the decontamination from Np; it has been reported that 75% of the Np initially in the dissolved feed ends up in the uranium product from partitioning that goes to uranium purification. Of that, 99.8% of this Np is recovered in the raffinate of the uranium purifica­tion cycle. A Np decontamination factor of DF > 150 has been reported for the uranium purification cycle (Baron 1993).