1. Fuel dissolution medium

In France, spent fuel is reprocessed at the La Hague plants using the PUREX (Plutonium Uranium Refining by Extraction) process [BN 3 652] . This process involves an initial stage of dissolving the fuel in hot, concentrated nitric acid, during which the uranium, plutonium, other actinides and most of the fission products are dissolved. As a result, throughout the process downstream of this first dissolution stage (uranium/plutonium/fission product separation, extraction, purification, vitrification gas treatment, acid recovery), nitric media at temperatures ranging from ambient to boiling and in varying concentrations,...