Abstract: | The electrochemical behavior of neptunium nitride, NpN, in the LiCl-KCl eutectic melt containing NpCl3 at 450, 500 and 550°C was investigated from the viewpoint of the application of electrochemical refining in a fused salt to nitride fuel cycle. The electrochemical dissolution of NpN began nearly at the potential theoretically evaluated, though this reaction was irreversible owing to small partial pressure of N2 in the salt and the reaction rate was slow. Under the electrolysis in the NpCl3-LiCl-KCl eutectic melt, NpN was dissolved into the salt as Np3+ at the anode, and Np metal was deposited at the cathode. About 0.5 g of Np metal was obtained by heating the deposit containing the salt at 800°C for 3.6 ks. |