Development and Applications of the Rapid Analysis of Post-Irradiation Debris (RAPID) Method to Nuclear Materials

Chemical analysis of nuclear materials is a well-developed area of research, through use of mass spectrometers and other destructive analysis techniques. These analyses are applicable to several nuclear fields, such as nuclear forensics, fuel characterization and modeling, and environmental monitoring. For nuclear forensics particularly, a rapid analytical chemistry technique can be useful, given the need for a quick turn-around of data in certain attribution cases for nuclear forensics. An analytical technique for low-level nuclear material analyses has been developed and applied to various samples at Oak Ridge National Laboratory (ORNL), named Rapid Analysis of Post-Irradiation Debris (RAPID). This technique combines a high-pressure ion chromatography unit and an inductively-coupled plasma mass spectrometer for a rapid, direct separation-detection method, with a turn-around of less than four hours per sample, including dissolution, analysis, and data processing. Analyzed samples include irradiated highly-enriched uranium, ORNL-developed, and UTK-developed surrogate nuclear “debris”. This dissertation will present the development of RAPID and its subsequent evolution and application to nuclear forensics, obtaining the sensitivity and accuracy for operational usage at ORNL. Additionally, a novel inline gamma detection technique was developed as an extension of RAPID and will be presented, demonstrating the feasibility of elementally-isolated gamma spectrometry and the benefit of having two complementary analytical techniques to fully characterize fission products in a short timeframe.