The elementary analyzer works on the principle of catalytic combustion and separation of the gases released during it. At the time of this combustion, the elements C, N, S are oxidized to CO2, H2O, NOx, SO2 and SO3. The NOx released during this oxidation are reduced to N2 and directly sent to the thermo-conductive detector (TCD).
The other liberated gases are retained on specific traps for CO2, SO2 and H2O then released one after the other and sent to the detection system. The sulfur compounds in the form of SO3 are reduced and then trapped in the form of SO2.
Volatile halogens are trapped on the silver wool at the outlet of the reduction tube. The amount of oxygen required to ensure complete combustion of the gases is managed by the equipment's analysis method. To avoid the formation of H2SO4 from SO2 and H2O as well as the condensation of water vapor, all the tubes are heated.
The thermo-conductive detector works on the principle of a difference in thermal conductivity between two gas streams. In a first chamber flows the reference gas flow (He). In a second chamber flows the He + analyte(s) mixture. The difference in conductivity between the two gases is proportional to the amount of elemental analyte(s).
Applications of this technique:
- Protein determination
- Verification of low N content in gluten-free products
- Tracking of C content in drugs (eg aspirin, etc.)
- C / N ratio in soils and sulfur in volcanic discharges
- Measuring stages of litter decomposition
- Checking the sulfur content in fuels