A quantitative light-isotope measurement system for climate and energy applications

• DOI: 10.1016/j.ijms.2021.116574
• Publication Date: 2021-03-14T05:22:31Z
• Authors: Robert P. Thorn; Andrew K. Gillespie; Cuikun Lin; Heather Higgins; Shelby Lacouture; Robert Baca; Baudilio Tejerina; Andrew A. Durso; Django Ian Jones; Ruth Ogu; Brett Neurohr; Trevor Dardik; Robert V. Duncan
• Keywords: 13. Climate action; 7. Clean energy; 01 natural sciences; 0104 chemical sciences

Abstract We describe the design, operation, and performance of a new instrumental configuration capable of quantitative determinations with sub-picomole accuracy of dilute concentrations of low mass species, such as H e 4 , H e 3 , N e 20 , and A r 40 , in a balance of stable hydrogen (H2, DH, and D2) gas. This inexpensive system may realize important applications in fields ranging from climate studies to hydrogen fusion energy research, thereby providing an expanded availability of this diagnostic within emerging energy systems research and development. These spectra, calibration curves, and determinations were obtained by using a novel method for the purification and subsequent removal of the hydrogen matrix gas, and an extensively modified commercial Fourier Transform Ion Cyclotron Resonance (FT-ICR) mass spectrometer with an electron impact (EI) ionizer. These high-resolution FT-ICR mass spectrometers have routinely achieved a resolution, R = m/Δm better than 10,000 Da at mass-3, with a mass resolution that scales as 1/m. These devices have easily resolved D2 from H e 4 , and DH from H e 3 . The performance of this upgraded instrument has demonstrated the ability to detect impurities from tiny air leaks, such as A r 40 and N e 20 , in the presence of the hydrogen matrix gas. While no concentration measurements of radioactive species have been attempted to date with this system, it is expected to easily resolve DT from D2H (a 0.0059 Da mass difference) and HT from all other mass-4 species.