Year
2008
Abstract
Safeguards accountancy at a nuclear fuel reprocessing facility depends on an accurate and timely measurement of accountable material (e.g., plutonium) mass in the head-end fuel dissolution tanks and in the various process streams within the remainder of the plant. Current methods based on destructive analysis of extracted samples can take days to complete and months to verify. An online method to directly and rapidly measing the mass of accountable materials in process streams is needed. Experiments have been conducted to extend a novel and highly selective separation technology that is based on a multistage-recognition process. It is an aqueous based (nitric acid) separation technique that uses both redox and complexation chemistry together to selectively isolate uranium (U) or plutonium (Pu) from complex matrices for nondestructive and destructive analysis. Essentially, accumulation of Pu or U is turned off and on with an applied dc potential. Distinctly different from pyroprocessing and traditional liquid and column extractions, only a potential step is required to accumulate and isolate components for non-destructive or destructive analysis. Results of this project will be presented including studies to 1) scale up sampling lab-based technology to realistic process sampling volumes, 2) demonstrate selectivity for U and Pu over surrogate actinides and fission products in a simulated dissolver solution, and 3) simulate non-destructive gamma analysis based on experimentally-determined separation factors. These studies will demonstrate the technology’s promise for direct, near-real time gamma spectroscopy measurements of Pu in dissolver solutions.