Method
Chromatographic system based on:
Chromatec-Crystal 5000/9000
Detectors:
TCD / TCD / FID
Packed columns:
Packed Column M, 3 m × 2 mm, HayeSep R (Porapak R), 80/100 mesh
Packed Column M, 3 m × 2 mm, NaX, 80/100 mesh
Injection system:
Chromatec or Valco 6-port valves with 1 mL and 2 mL sample loop volumes
Heated transfer line
Gas flow indicator
Additional data processing software:
Chromatec Gas
Additional equipment:
Hydrogen generator
Air compressor
Gas fittings kit 4.078.000 – 2 pcs. (argon and helium)
Combined catalytic purification filter 20.0-03
Certified gas mixtures (PGS, IPG) for instrument calibration
Adjustable pneumatic resistance RPS 5.150.019 for operation with standard gas mixtures and sampling devices
Method Description
GOST 31371 Part 3. Determination of hydrogen, helium, oxygen, nitrogen, carbon dioxide, and hydrocarbons up to C8 using two packed columns.
The determination of nitrogen, carbon dioxide, and hydrocarbons from C1 to C8 is carried out by gas chromatography using two columns.
A molecular sieve 13X column (Packed Column M, 3 m × 2 mm, NaX 80/100 mesh) connected to a thermal conductivity detector (TCD) is used for the separation and detection of hydrogen, helium, oxygen, and nitrogen.
A HayeSep R or Porapak R column (M, 3 m × 2 mm, HayeSep R (Porapak R), 80/100 mesh) connected in series to a thermal conductivity detector (TCD) and a flame ionization detector (FID) is used for the separation and detection of nitrogen, carbon dioxide, and hydrocarbons from C1 to C8.
The analytical results are then combined.
GOST 31371.3
Molar fraction ranges of components covered by GOST 31371.3
| Component | Formula | Molar Fraction, % |
|---|---|---|
| Helium | He | 0.01–0.5 |
| Hydrogen | H2 | 0.01–0.5 |
| Oxygen | O2 | 0.1–0.5 |
| Nitrogen | N2 | 0.1–40 |
| Methane | CH4 | 50–100 |
| Carbon Dioxide | CO2 | 0.1–30 |
| Ethane | C2H6 | 0.1–15 |
| Propane | C3H8 | 0.001–5 |
| Butanes | C4H10 | 0.0001–2 |
| Pentanes | C5H12 | 0.0001–1 |
| Hexanes–Octanes | — | 0.0001–0.5 |
