A review on UREX processes for nuclear spent fuel reprocessing

This paper presents a review on the UREX and variants of UREX + processes used for reprocessing of the spent nuclear fuels. The UREX + process consists of nine versions from which seven product streams are obtained. Uranium and technetium are recovered as separate products with the yield > 99% in the first stage of the UREX process. Cesium and strontium are recovered from the UREX waste using CCD-PEG or FPEX process. Plutonium and neptunium are separated using NPEX process with high level of impurity. The NPEX raffinate is treated in the TRUEX process from which minor actinides along with rare-earth elements are separated. Purification of minor actinides from the rare-earth elements is carried out in the Cyanex 301 process. The technologies used for each reprocessing process are described in detail. The flowsheets and process chemistry of all the versions of UREX processes are also reported and discussed in detail. The key issues related to UREX processes for reprocessing the spent nuclear fuels have been summarized. The strategy of the non-proliferation resistance using the advanced reprocessing process is described in the present work.