Method of eliminating radioactive materials in electrolytes during electropolishing

Purpose: To effectively recover acids and metal ions from electrolytes after decontamination thereby prevent accumulation of radioactive materials in the electrolytes. Method: Metal surfaces of equipments, components or the likes contaminated with radioactive materials are decontaminated through electropolishing and metal oxides stripped to eliminate from metal surfaces are subjected to solid-liquid separation from electrolytes by using filters or the likes. Successively, they are separated into metal ions coexistent in the electrolytes and acids as the main ingredients of the electrolytes by using diffusion dialysis membranes to recover the acids. Further, after adjusting the liquid wastes after the separation of the acids to such a pH range as not depositing metal ions as hydroxides, they are transferred into a recovery vessel, to which electric current is caused to flow thereby deposit most of metal ions as solid metals on cathodes and then taken out of the liquid. Metal ions remaining in the liquid are eliminated by means of ion exchange resins or the likes. (Sekiya, K.)