Mass Balance Evaluation of Pyrochemical Process for Reprocessing used Fuel Salt of Molten Chloride Salt Fast Reactor

A pyrochemical process is proposed to reprocess used fuel salt taken from a molten chloride salt fast reactor.The proposed process is constituted of several steps using chemical and electrochemical reactions in the chloride salt / liquid Bi system.To investigate the technical feasibility of the proposed pyrochemical process, the mass balances of actinides (U, Pu, Np, Am, Cm) and fission products (La, Cc, Pr, Nd, Gd, Sr and Cs) were evaluated based on their thermodynamic properties (their distribution behaviors between the chloride salt and liquid Bi).Demonstration tests of the pyrochemical steps were performed to investigate the distribution behaviors of U, lanthanides, Sr and Cs in this study.The evaluated mass balances showed that almost all actinides were to be recycled as a new fuel salt and most of lanthanides fission products were to be stabilized in a waste form, which indicates the basic feasibility of the proposed pyrochemical process was confirmed.