Isotopic ratio of Pu released from fuel cycle facilities - importance of radiochemically pure ~(236)Pu as

摘要

In order to characterize the possible release of Pu from nuclear fuel cycle facilities, the various isotopic compositions of Pu from different types of reactors have been examined. As a result, for assessment of radiological impact and identification of source of any release, it is shown that precise determination of the isotopic abundances of ~(238)Pu and ~(242)Pu will be required. In order to meet this requirement, the advantage of the utilization of ~(236)Pu as a tracer is emphasized. A technique, using an electron LINAC, was therefore developed to produce radiochemically pure ~(236)Pu by the bremsstrahlung irradiation of ~(237)Np. Further, it is demonstrated that ~(236)Pu can be successfully produced by this method with a ~(238)Pu impurity of less than 0.06% of the total α-activity of ~(236)Pu.