On-Line Monitoring of Gas-Phase Molecular Iodine Using Raman and Fluorescence Spectroscopy Paired with Chemometric Analysis

• Published in: Environmental science & technology Vol. 55; no. 6
• Main Authors: Felmy, Heather M., Clifford, Andrew J., Medina, Adan Schafer, Cox, Richard M., Wilson, Jennifer M., Lines, Amanda M., Bryan, Samuel A.
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 07.01.2021
• Subjects: ENVIRONMENTAL SCIENCES; INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY; SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
• ISSN: 0013-936X; 1520-5851

Molten salt reactors (MSRs) have the potential to safely support green energy goals. However, licensing and deployment of these systems will be aided through development of new technology. This includes on-line monitoring tools for real-time compositional analysis. Of particular interest is quantifying iodine within reactor off-gas streams to support design and operational control of reactor off-gas treatment systems. Here we discuss the development of advanced Raman spectroscopy systems for the on-line analysis of I2(g) within the gas phase. Signal response is explored with two Raman instruments utilizing a 532 nm and a 671 nm excitation source, as a function of I2(g) pressure and temperature. Furthermore, the applicability of chemometric modeling for advanced analysis of data is explored. Raman spectroscopy paired with chemometric analysis is demonstrated to be a powerful route to analyzing I2(g) composition within the gas phase, which lays the foundation for applications within molten salt reactor off-gas analysis and other significant chemical processes producing iodine species.