PUREX

For other uses, see Purex (disambiguation).
Not to be confused with Pyrex.
Reprocessing of spent nuclear fuel by the PUREX method, first developed in the 1940s to produce plutonium for nuclear weapons,[1] was demonstrated commercially in Belgium to partially re-fuel a LWR in the 1960s.[2] This aqueous chemical process continues to be used commercially to separate reactor grade plutonium (RGPu) for reuse as MOX fuel. It remains controversial, as plutonium can be used to make nuclear weapons.[3][4]
The most developed, though commercially unfielded, alternative reprocessing method, is Pyroprocessing,[5] suggested as part of the depicted metallic-fueled, Integral fast reactor (IFR) a sodium fast reactor concept of the 1990s. After the spent fuel is dissolved in molten salt, all of the recyclable actinides, consisting largely of plutonium and uranium though with important minor constituents, are extracted using electrorefining/electrowinning. The resulting mixture keeps the plutonium at all times in an unseparated gamma and alpha emitting actinide form, that is also mildly self-protecting in theft scenarios.[6]

PUREX (plutonium uranium reduction extraction) is a chemical method used to purify fuel for nuclear reactors or nuclear weapons.[7] PUREX is the de facto standard aqueous nuclear reprocessing method for the recovery of uranium and plutonium from used nuclear fuel (spent nuclear fuel, or irradiated nuclear fuel). It is based on liquid–liquid extraction ion-exchange.[8]

PUREX is applied to spent nuclear fuel, which consists primarily of very high atomic-weight (actinoid or "actinide") elements (e.g. uranium, plutonium, americium) along with smaller amounts of material composed of lighter atoms, notably the fission products produced by reactor operation.

A simplified plutonium extraction flow chart.

The actinoid elements in this case consist primarily of the unconsumed remains of the original fuel (typically U-235, U-238, and/or Pu-239).

  1. ^ Greenwood, pp. 1255, 1261
  2. ^ "Reprocessing plants, world-wide". European Nuclear Society. Archived from the original on 22 June 2015. Retrieved 29 July 2008.
  3. ^ An Evaluation of the Proliferation Resistant Characteristics of Light Water Reactor Fuel with the Potential for Recycle in the United States
  4. ^ Is U.S. Reprocessing Worth The Risk?, Steve Fetter and Frank N. von Hippel, Arms Control Today, September 1, 2005.
  5. ^ L.C. Walters (September 18, 1998). "Thirty years of fuels and materials information from EBR-II". Journal of Nuclear Materials. 270 (1): 39–48. Bibcode:1999JNuM..270...39W. doi:10.1016/S0022-3115(98)00760-0.
  6. ^ [1] PUREX and PYRO are not the same, Hannum, Marsh, Stanford.
  7. ^ Gregory Choppin; Jan-Olov Liljenzin; Jan Rydberg (2002). Radiochemistry and Nuclear Chemistry, Third Edition. p. 610. ISBN 978-0-7506-7463-8.
  8. ^ Paiva, A. P.; Malik, P. (2004). "Recent advances on the chemistry of solvent extraction applied to the reprocessing of spent nuclear fuels and radioactive wastes". Journal of Radioanalytical and Nuclear Chemistry. 261 (2): 485–496. doi:10.1023/B:JRNC.0000034890.23325.b5. S2CID 94173845.