Absolute isotope ratios of carbon dioxide – a feasibility study. Issue 11 (9th September 2020)

• Record Type: Journal Article
• Authors: Flierl, Lukas; Rienitz, Olaf; Brewer, Paul J.; Meijer, Harro A. J.; Steur, Farilde M.
• Is Part Of: Journal of analytical atomic spectrometry. Volume 35:Issue 11(2020)
• Page Start: 2545
• Page End: 2564
• Publication Date: 2020-09-09
• Subjects: Atomic spectra -- Periodicals; Atomic absorption spectroscopy -- Periodicals; 543.0858
• DOI: 10.1039/d0ja00318b
• Languages: English
• ISSNs: 0267-9477

Abstract

Abstract : First attempts of adapting the gravimetric mixture method for absolute isotope ratios of CO2 . Abstract : One way of obtaining isotope ratios, traceable to the International System of Units, is the gravimetric isotope mixtures method. Adapting this method to carbon dioxide is challenging since measuring all twelve isotopologues at once with a gas mass spectrometer is currently not possible. The calculation of the mass bias correction factors is no straightforward task due to the fact that the isotopic equilibrium has to be considered. This publication demonstrates a potential way of adapting this method to carbon dioxide while considering isotope equilibrium. We also show how we prepared binary blends from enriched/depleted carbon dioxide parent gases and how equilibrating the different gases by heating affects the measurements. Furthermore, we reveal mathematical limitations of our approach when the gases are not in isotope equilibrium and which issues occur due to measurement limitations. In a simulation, using authentic data, we asses our approach in terms of achievable uncertainties and discuss further improvements, like using atomic spectroscopy methods.