Monitoring Xenon Capture in a Metal Organic Framework Using Laser-Induced Breakdown Spectroscopy

Molten salt reactor operation will necessitate circulation of a cover gas to remove certain evolved fission products and maintain an inert atmosphere. The cover gas leaving the reactor core is expected to contain both noble and non-noble gases, aerosols, volatile species, tritium, and radionuclides and their daughters. To remove these radioactive gases, it is necessary to develop a robust off-gas system, along with novel sensors to monitor the gas stream and the treatment system performance. In this study, a metal organic framework (MOF) was engineered for the capture of Xe, a major contributor to the off-gas source term. The engineered MOF column was tested with a laser-induced breakdown spectroscopy (LIBS) sensor for noble gas monitoring. The LIBS sensor was used to monitor breakthrough tests with various Xe, Kr, and Ar mixtures to determine the Xe selectivity of the MOF column. This study offers an initial demonstration of the feasibility of monitoring off-gas treatment systems using a LIBS sensor to aid in the development of new capture systems for molten salt reactors.

Automated summary

The operation of a molten salt reactor requires the circulation of a cover gas to remove radioactive gases and maintain an inert atmosphere. This study developed a metal organic framework (MOF) for the capture of xenon (Xe), a major component of the off-gas. The MOF was tested using a laser-induced breakdown spectroscopy (LIBS) sensor to monitor noble gases, and the study demonstrated the feasibility of using LIBS sensors to aid in the development of new capture systems for molten salt reactors.