Abstract:

Electrorefining is the key process in used nuclear fuel dry reprocessing.Aiming at the electrorefining behavior of lithium chloride and potassium chloride（LiCl-KCl） molten salt environment，a kinetic model was established based on the reaction process at the electrode surface.The model was validated the experimental data.The model could predict the dissolution of spent fuel in the anode and the dynamic characteristics of metal deposition at the cathode，as well as the evolution of the partial current，electrode potential and ion concentration in molten salt of the elements involved in the electrorefining process.In addition，the model could also simulate the process of electrorefining in multi-element complex system.When the Zr，U，Pu and rare earth metal were used as the anode，simulation results showed that the actinides and rare earth were dissolved gradually on the anode，but the Zr was hardly dissolved.In the molten salt，the concentration of plutonium was increased but the concentration of uranium was decreased.After the deposition of plutonium，the deposition rate of uranium was decreased，with little rare earth or Zr depositing on the cathode.

Key words: used nuclear fuel, pyroprocessing, electrorefining, modeling