Treatment of spent radioactive organic solvents from nuclear fuel reprocessing plant: Advances and perspectives

The mixture of tributyl phosphate/odourless kerosene (TBP/OK) is employed in the plutonium uranium extraction (PUREX) process for nuclear fuel cycle. The radioactive spent organic solvent is produced during the operation of the nuclear fuel reprocessing plants. The treatment of the spent organic solvents containing tributyl phosphate in the reprocessing plants remains a difficult problem due to the complex chemical composition and radioactivity. In this paper, different treatment and disposal technologies of spent organic solvent were analyzed, summarized and compared, including advanced oxidation processes, such as dry oxidation (incineration and pyrolysis), wet oxidation (acid digestion and direct oxidation, plasma treatment, supercritical water oxidation, mediated electrochemical oxidation and Fenton oxidation), solidification, distillation, alkaline hydrolysis and absorption. The principles of the treatment and disposal technologies, their characteristics and applications were briefly introduced, and the future research directions were discussed. This is the first review article to systematically summarize and analyze the treatment of spent radioactive organic solvents from nuclear fuel reprocessing plant, which is helpful for readers to comprehensively understand the current status and development direction of the treatment of radioactive waste organic solvents.