Total Nitrogen and Carbon
A Thermo FlashSmart Elemental Analyzer is available to analyze solid samples for %C and %N using dry combustion followed by gas chromatography. The CN analyzer oxidizes organic matter at very high temperatures (>1000°C) in the presence of O2 and oxidation catalyzing reagents.
Organic carbon compounds are oxidized to CO2, and nitrogen compounds are oxidized to N-oxides. These gases then pass through a reduction column which removes O2 and reduces the N-oxides to N2. The concentrations of CO2 and N2 gases are then determined by chromatography.