Improvements in the gaseous hydrogen-water equilibration technique for hydrogen isotope ratio analysis

T.B. Coplen; J. D. Wildman; J. Chen

doi:10.1021/ac00009a014

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Improvements in the gaseous hydrogen-water equilibration technique for hydrogen isotope ratio analysis

T.B. Coplen·J. D. Wildman·J. Chen

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Abstract

Improved precision in the H 2 -H 2 O equilibration method for δD analysis has been achieved in an automated system. Reduction in 1- σ standard deviation of a single mass-spectrometer analysis to 1.3 ‰ is achieved by (1) bonding catalyst to glass rods and assigning use to specific equilibration chambers to monitor performance of catalyst, (2) improving the apparatus design, and (3) reducing the H 3 + contribution of the mass-spectrometer ion source. For replicate analysis of a water sample, the standard deviation improved to 0.8 ‰ . H 2 S-bearing samples and samples as small as 0.1 mL can be analyzed routinely with this method.

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T.B. Coplen, J. D. Wildman, J. Chen. 2002-05-01. Improvements in the gaseous hydrogen-water equilibration technique for hydrogen isotope ratio analysis. https://doi.org/10.1021/ac00009a014

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