Innovative Waste Management in the Mercury Loop of the EURISOL Multi-MW Converter Target

The choice of mercury as target material imposes various questions concerning the safe operation of such a system that are related to the physical and chemical properties of the target material itself and the nuclear reaction products produced within the target during its life time of several decades. Therefore, a subtask was created within the EURISOL-DS project that is concerned with studying an innovative waste management for the generated radioactivity by chemical means. Such a study strongly depends on the radioactive inventory and its distribution throughout the target and loop system. Radioactive inventory calculations were performed within task 5 [6]. The distribution of nuclear reaction products and their chemical state that can be expected within the target and loop system is one of the topics covered in this report. Based on the results obtained by theoretical studies as well as laboratory scale experiments, the feasibility of waste reduction using chemical methods, both conventional (e.g. leaching, distillation) and innovative (e.g. surface adsorption) are studied experimentally. The results and their implications on separation procedures that can be favourably applied to a spallation target system are discussed with respect to both handling of the radioactive waste and extraction of valuable nuclides for medical, scientific and industrial applications.