The uncertainty of carbon dioxide determination in gaseous mixtures

The uncertainty of carbon dioxide determination in gaseous mixtures is evaluated for the chromatographic technique with sample introduction via its displacement by a saturated aqueous solution of sodium chloride. It is shown that the main source of the uncertainty comes from the errors in reference mixtures preparation and other stages of calibration. The expanded uncertainty at 0.95 level of confidence is 0.1-0.2 mol% for a carbon dioxide concentration range of 0.3-100.0 mol%.