Doctoral Defense – Hope Lackey
About the event
Group: Dr. Xiaofeng Guo
Title: Advancing Optical Spectroscopic and Chemometric Approaches to Solve Key Analytical Challenges in the Nuclear Fuel Cycle
Abstract:
To close the nuclear fuel cycle, innovative work in the development and scaling up of spent fuel recycling schemes is necessary. Spent fuel and legacy waste reprocessing must be undertaken and processing efforts accelerated to reduce current inventories of material in interim storage and to improve the environmental sustainability of nuclear reactor fuel production. This work contributes to the growing body of research dedicated to the demonstration of optical spectroscopy as a robust, trusted tool for real-time monitoring and characterization of chemical systems in the nuclear fuel cycle. Specifically, this work focuses on promoting the reduction of grab sampling from radioactive material process streams in three ways. The overarching goal of this work is to advance chemometric data analysis of optical spectra in challenging measurement systems, analyzing chemically complex samples on the microfluidic scale and under measurement scenarios encompassing substantial spectral variance.
Firstly, by providing real time data for chemical systems, on-line monitoring has been demonstrated to reduce the required number of grab samples required to maintain safeguards standards. A method is developed produce prediction models using unreferenced, single-beam spectroscopy as a real-time measurement tool even in on-line, hazardous, and physically inaccessible systems. Secondly, the use of optical spectroscopic techniques for measurement on microfluidic devices (MFDs) is explored with the aim of reducing necessary sample size for comprehensive grab sample analysis. Sensor fusion, including Visible, NIR, and Raman spectroscopies, is used to increase quantitative and qualitative model performance from a single sample on MFDs.
This work lays the groundwork for future applications of optical spectroscopic techniques on the next generation of microfluidic platforms and for deployment of optical spectroscopic techniques in challenging on-line monitoring scenarios.