Application of ionic liquids in nuclear fuel reprocessing

Abstract

The nuclear fuel reprocessing, as the essential part of nuclear fuel cycle, is of great significance from the point of view of both nuclear safety and sustainable development of nuclear energy. Room temperature ionic liquids (RTILs) regarded as “new generation green solvents” have recently received an ever-increasing amount of interest in nuclear fuel reprocessing due to their unique physical and chemical properties. They can be used in aqueous reprocessing as environmentally benign alternatives to volatile organic solvents for traditional liquid-liquid extraction of high level radioactive nuclides. They are also applicable in non-aqueous reprocessing by substituting caustic molten salts for electro-deposition of metal ions. Herein, we reviewed the recent basic researches on the utility of RTILs in nuclear fuel reprocessing, from which the key scientific issues on their practical application were summarized. In addition, it is well known that nuclear fuel reprocessing involves high-level radioactive matter, and full realization of the potential application of RTILs in nuclear fuel reprocessing requires a comprehensive knowledge of stability and properties of RTILs under radiation. Therefore, the recent investigations of radiation effects on RTILs were also selectively described in this paper, and the feasibility of RTILs as alternative media for separations of highly radioactive nuclides from spent nuclear fuel was assessed from the radiation chemistry aspect. Finally, further basic studies on the application of RTILs in the nuclear fuel reprocessing were prospected.