Determination of Carbon (C), Hydrogen (H), Nitrogen (N), Sulfur (S), and Oxygen (O) by Combustion Analysis (CAT#: STEM-EA-0001-ZJF)

The CHN and CHNS analysis is based on the classical PreglDumas method where samples are combusted in a pure oxygen environment, with the resultant combustion gases measured in an automated fashion. The sample is prepared, introduced into the combustion chamber and burned at high temperature under pure oxygen. The resulting gas mixture and helium carrier gas pass through various reductive and catalytic zones to convert the gas mixture into CO2, H2O, N2, and SO2. The gasses are separated using gas chromatography and quantified with a thermal conductivity detector.
The oxygen determination is based on the classical Unterzuacher method which incorporates the modifications of Oita, Conway and Culmo. The sample is pyrolyzed in a helium/ hydrogen (95%:5%) atmosphere at 1,000 °C. The resulting products of reaction containing oxygen are converted to carbon monoxide over the platinized carbon reagent. The carbon monoxide and other gases pass through a scrubber where interferences are removed. The carbon monoxide is then controlled, separated and determined in the same fashion as above.

Pharmaceuticals, polymers, chemicals, environment, energy, etc.

1. Combustion
2. Reduction
3. Mixing
4. Separation
5. Detection

• CHNS/O Analyzer
• Sample material: solids, liquids, volatile and viscous samples.