Radioactive waste disposal and reduction of the waste emission using highly-selective separation membranes

The volume of high-level radioactive liquid wastes from nuclear plants should be reduced for realization of waste management and disposals. For this purpose various methods have been proposed and examined. The present concerns fabrication of separation-membrane devices which efficiently extract and separate hazardous substances such as actinide elements by forming specific compounds. The reagents for this reaction, called the transfer carrier, were examined and, as the most promising one, TODGA (N, N, N', N'-tetraoctyl-3-oxapentane-1, 5-diamide) was chosen and synthesized. The efficiency for this separating membrane-device was examined using cerium, as a non-radioactive compound, for actinide elements as a function of nitric acid concentration, as was also verified the durability of the device fabricated with expected results. (S. Ohno)