Gases for chromatography
Chromatography is a separation method that allows a mixture to be broken down into the different components that make it up. It is a widely used laboratory and analysis technique based on the principle of the mobile and stationary phase.
Which carrier gas do you need for your analysis?
Discover our range of gases for each type of chromatographic analysis.
Pure gases & mixtures for chromatography
Air Liquide supplies gases for chromatographic analysis to universities and research laboratories. Our pure gases and mixtures are supplied with a certificate. Custom gas mixtures can also be made on request.
Discover our solutions for gas, liquid and supercritical chromatography.
Gas chromatography - use, process and areas of application
Mission
Gas chromatography, also abbreviated to GC, can separate mixtures into individual chemical compounds and is used in a variety of ways to analyse components that are gaseous or can be vaporised.
Process
An inert gas is often used as the mobile phase, which as a carrier gas pushes the sample through the separation column. Depending on the polarity and vapor pressure of the individual gas molecules, the various components of the sample remain in the stationary phase of the column for different lengths of time. After passing through the column, the detector at the end of the column measures the exit time.
The electronic signals of the detector are recorded in the so-called chromatogram depending on the time since the injection, the retention time:
- The chromatogram shows the concentration of the components as a function of time in the form of peaks.
- Under constant chromatographic conditions, the retention time of the peaks is characteristic of a compound and can thus provide qualitative information about the components contained in the sample. For this purpose, a comparison standard of the components assumed to be in the sample is required.
- Finally, the peak area is used to quantify the component.
Areas of application
Gas chromatographs are among the most important analysis devices in research and industrial laboratories. Even complex mixtures can be analyzed both qualitatively and quantitatively. In combination with a mass spectrometer, even small amounts of substance can be detected and structural elucidation can be carried out. Areas of application are primarily analyzes in medicine, biology, food chemistry, environmental analysis and forensics.
Do I need other operating gases or test gases in addition to a carrier gas - maybe even according to ISO 17025?
As carrier gases – optimally matched to the respective detector combinations such as GC-FID, GC-WLD, GC-ECD, GC-MS.
Depending on the detector, other operating gases can be used in addition to the carrier gas gases may be required in addition to the carrier gas – for example flame gases to generate a flame, fuel gases for combustion or gases for the ionization or methanisation process.
In addition, the detectors must be calibrated. Appropriate test gases are required for this. Depending on the use and application - such as an accredited laboratory, official or legal requirements or approval procedures - these should be traceable to international calibration standards such as NIST (National Institute for Standardization and Technology) or VSL (Van Swinden Laboratory) or from an accredited laboratory and be provided with a DAkkS calibration certificate according to ISO 17025.
Let the Mixture Guide guide you through your application and standard mixtures for operating gases and test gases - or define your individual calibration gas according to your needs in the define my own mixture area.
Carrier gases and operating gases for the most common detector types such as thermal conductivity detectors or flame ionization detectors
- Select the combination of gas chromatograph and detector you use
- Select the range of the target detection limit
- You will find suitable carrier gases as well as the operating gases that may be required for functionality
- With a click on the entry you will receive further information on the respective gases, such as purity or impurities, directly in the Air Liquide gas catalogue
How to get the best results from your chromatography equipment?
To ensure that the results of your chromatographic analysis are as reliable as possible, you must consider the following:
Choose the right carrier gas for your chromatographic analysis
It is important to choose the right carrier gas - the most common are hydrogen, helium, argon, nitrogen and air - with the right level of purity. This way you get accurate and consistent measurement results.
Air Liquide's ALPHAGAZ™ range has been specifically developed for laboratories and research. These gases are available in two qualities:
ALPHAGAZ™ 1: for analyzes from % to ppm
ALPHAGAZ™ 2: for analyzes from ppm to ppb
Contact our experts to guide you.
Prevent contamination of installations and pipes
Each time a new gas cylinder is connected, the equipment should be checked and flushed. This is to eliminate any risk of contamination. If this procedure is not performed or is performed incorrectly, it may affect the quality of the measurement results.
Chromatographic equipment compatibility
To obtain the best results, it is necessary to check if the equipment is suitable for the analysis of the desired substance and if the measuring system can perform the analysis in the expected concentration range (from percentages to very low ppb levels ).
What chromatography equipment should I use?
Our Air Liquide experts will be happy to advise you on the choice of equipment and answer your questions on gas calibration, pipe flushing and laboratory analyses.
How to choose the right gas for chromatography?
Select the chromatographic separation technique and application below to find out which gases and purities you need.
Coupling gas chromatography and mass spectrometry GC-MS
Gas Quality for GC-MS Gas Chromatography
See below the most suitable gas and purity for your analyser:
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|---|---|---|---|---|
| Gas phase sample
(mol/mol) |
% | 0.1% | 0.01% | 1ppm | <1ppm |
Recommended gases :
| Carrier gas | Argon | ALPHAGAZ 1 Ar | ALPHAGAZ 2 Ar |
|---|---|---|---|
| Helium | ALPHAGAZ 1 He | ALPHAGAZ 2 He | |
| Hydrogen | ALPHAGAZ 1 H₂ | ALPHAGAZ 2 H₂ | |
| Hydrogen | Generator | ||
| Nitrogen | ALPHAGAZ 1 N₂ | ALPHAGAZ 2 N₂ | |
| Nitrogen | Generator | ||
| Make-up | Argon | ALPHAGAZ 1 Ar | |
| Helium | ALPHAGAZ 1 He | ALPHAGAZ 2 He | |
| Hydrogen | ALPHAGAZ 1 H₂ | ALPHAGAZ 2 H₂ | |
| Hydrogen | Generator | ||
| Nitrogen | ALPHAGAZ 1 N₂ | ALPHAGAZ 2 N₂ | |
| Nitrogen | Générateur | ||
| Open Split | Helium | ALPHAGAZ 1 He | ALPHAGAZ 2 He |
| Chemical ionisation | Ammonia | N45 | |
| Isobutane | N35 | ||
| Methane | N45 | ||
| Fast Atomic Bombardment | Argon | ALPHAGAZ 1 Ar | |
| Xenon | N48 | ||
Supercritical phase chromatography, SFC
Gas quality for supercritical phase chromatography, SFC
See below the most suitable gas and purity for your analyser:
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|
Recommended gases:
| Mobile phase | Carbon Dioxide | ALPHAGAZ CO₂ SFC |
|---|
High pressure liquid chromatography, HPLC
Gas quality for high pressure liquid chromatography
Check below the most suitable gas and purity for your analyzer
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|
Recommended gases :
| Solvent purge | Helium | ALPHAGAZ 1 He |
|---|
Coupling liquid chromatography and mass detector, LC-MS
Gas quality for liquid chromatography and mass detector
See below the most suitable gas and purity for your analyzer:
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|
Recommended gases :
| Curtain gas | Nitrogen | ALPHAGAZ 1 N2 |
|---|---|---|
| Nitrogen | Generator | |
| Nebulization or Collision gas |
Nitrogen | ALPHAGAZ 1 N2 |
| Nitrogen | Generator | |
| Air | ALPHAGAZ 1 AIR | |
| Air | Generator | |
| Venturi gas | Air | ALPHAGAZ 1 AIR |
| Air | Generator | |
| Nitrogen | ALPHAGAZ 1 N2 | |
| Nitrogen | Generator | |
| Chemical ionisation | Ammonia | N45 |
| Isobutane | N35 | |
| Methane | N45 | |
| Solvent purge | Helium | ALPHAGAZ 1 He |
Reduced gas analyser, RGA
Gas Quality for GC-RGA Gas Chromatography
See below the most suitable gas and purity for your analyser:
Measurement range :
| Sample in solution | >g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|---|---|---|---|---|
| Sample gas phase
(mole/mole) |
% | 0.1% | 0.01% | 10ppm | <1ppm |
Recommended gases :
| Carrier gas | Argon | ALPHAGAZ™ 2 Ar |
|---|---|---|
| Make-up | Argon | ALPHAGAZ™ 2 Ar |
Detectors
Electron capture detector (pulsed discharge) PD-ECD
Gas Quality for PD-ECD Gas Chromatography
See below the most suitable gas and purity for your analyzer:
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|---|---|---|---|---|
| Gas phase sample (mol/moe) | % | 0.1% | 0.01% | 10ppm | <1ppm |
Recommended gases :
| Curtain gas | Nitrogen | ALPHAGAZ 1 N₂ |
|---|---|---|
| Helium | ALPHAGAZ 2 He | |
| Make-up | Nitrogen | ALPHAGAZ 2 N₂ |
| Helium | ALPHAGAZ 2 He | |
| Discharge gas | Helium | ALPHAGAZ 2 He |
| Cleaning | Hydrogen | ALPHAGAZ 2 H₂ |
| Hydrogen | Générateur |
Electron Capture Detector, ECD
Gas Quality for GC-ECD Gas Chromatography
See below the most suitable gas and purity for your analyzer:
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|---|---|---|---|---|
| Gas phase sample (mol/mol) | % | 0.1% | 0.01% | 10ppm | <1ppm |
Recommended gases :
| Carrier gas |
Helium |
ALPHAGAZ 2 He |
|---|---|---|
| Nitrogen |
ALPHAGAZ 2 N₂ |
|
| Mixture 5 % CH4/Ar | ALPHAGAZ MIX 5% CH4/Ar | |
| Mixture 10 % CH4/Ar | ALPHAGAZ MIX 10% CH4/Ar | |
|
Make-up gas |
Mixture 10 % CH4/Ar | ALPHAGAZ MIX 10% CH4/Ar |
| Mixture 5 % CH4/Ar | ALPHAGAZ MIX 5% CH4/Ar | |
| Nitrogen |
ALPHAGAZ 2 N₂ |
|
|
Helium |
ALPHAGAZ 2 He | |
| Cleaning | Hydrogen | ALPHAGAZ 2 H₂ |
| Hydrogen | Generator |
Chemiluminescence detector, SCD
Gas Quality for GC-SCD Gas Chromatography
See below the most suitable gas and purity for your analyser:
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|---|---|---|---|---|
| Gas phase sample (mol/mol) | % | 0.1% | 0.01% | 10ppm | <1ppm |
Recommended gases :
| Carrier gas | Argon | ALPHAGAZ 2 Ar |
|---|---|---|
| Helium | ALPHAGAZ 2 He | |
| Nitrogen | ALPHAGAZ 2 N₂ | |
| Make-up | Argon | ALPHAGAZ 2 Ar |
| Helium | ALPHAGAZ 2 He | |
| Nitrogen | ALPHAGAZ 2 N₂ | |
| Oven (Air) | Air | ALPHAGAZ 2 AIR |
| Furnace (H₂) | Hydrogen | ALPHAGAZ 2 H₂ |
| Hydrogen | Generator | |
| Ozone production | Air | ALPHAGAZ 2 AIR |
| Oven (O₂) | Oxygen | ALPHAGAZ 2 O₂ |
Thermal conductivity detector, hot wire detector or TCD
Gas Quality for GC-TCD Gas Chromatography
See below the most suitable gas and purity for your analyser:
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|---|---|---|---|---|
| Gas phase sample (mol/mol) | % | 0.1% | 0.01% | 10ppm | <1ppm |
Recommended gases :
| Carrier gas | Helium | ALPHAGAZ 1 He |
|---|---|---|
| Nitrogen | ALPHAGAZ 1 N₂ | |
| Nitrogen | Generator | |
| Hydrogen | ALPHAGAZ 1 H₂ | |
| Hydrogen | Generator | |
| Make-up | Argon | ALPHAGAZ 1 Ar |
| Helium | ALPHAGAZ 1 He | |
| Nitrogen | ALPHAGAZ 1 N₂ | |
| Nitrogen | Generator | |
| Hydrogen | ALPHAGAZ 1 H₂ | |
| Hydrogen | Generator |
Atomic emission detector, AED
Gas Quality for GC-AED Gas Chromatography
See below the most suitable gas and purity for your analyser:
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|---|---|---|---|---|
| Gas phase sample (mol/mol) | % | 0.1% | 0.01% | 10ppm | <1ppm |
Recommended gases :
| Carrier gas | Helium | ALPHAGAZ 1 He |
|---|---|---|
| Nitrogen | ALPHAGAZ 1 N₂ | |
| Nitrogen | Generator | |
| Hydrogen | ALPHAGAZ 1 H₂ | |
| Hydrogen | Generator | |
| Make-up | Argon | ALPHAGAZ 1 Ar |
| Helium | ALPHAGAZ 1 He | |
| Nitrogen | ALPHAGAZ 1 N₂ | |
| Nitrogen | Generator | |
| Hydrogen | ALPHAGAZ 1 H₂ | |
| Hydrogen | Generator |
Helium Ionization Detector (Pulse discharge), HID
Gas Quality for HID Gas Chromatography
See the most suitable gas and purity for your analyser below:
Meaurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|---|---|---|---|---|
| Gas phase sample (mol/mol) | % | 0.1% | 0.01% | 10ppm | <1ppm |
Recommended gases :
| Carrier gas | Helium | ALPHAGAZ 2 He |
|---|---|---|
| Make-up | ||
|
Purging of the optics |
ALPHAGAZ 1 He |
Flame ionisation detector or FID
Gas Quality for GC-FID Gas Chromatography
See below the most suitable gas and purity for your analyser:
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|---|---|---|---|---|
| Gas phase sample (mol/mol) | % | 0.1% | 0.01% | 10ppm | <1ppm |
Recommended gases :
| Carrier gas | Argon | ALPHAGAZ 1 Ar | ALPHAGAZ 2 Ar |
|---|---|---|---|
| Hydrogen | ALPHAGAZ 1 H₂ |
ALPHAGAZ 2 H₂ |
|
| Generator | |||
| Helium | ALPHAGAZ 1 He | ALPHAGAZ 2 He | |
| Nitrogen | ALPHAGAZ 1 N₂ | ALPHAGAZ 2 N₂ | |
| Generator | |||
| Flame (Air) | Air | ALPHAGAZ 1 AIR | ALPHAGAZ 2 AIR |
| Generator | |||
| Flame (H₂) | Hydrogen | ALPHAGAZ 1 H₂ | ALPHAGAZ 2 H₂ |
| Generator | |||
| Make-up | Argon | ALPHAGAZ 1 Ar | ALPHAGAZ 2 Ar |
| Hydrogen | ALPHAGAZ 1 H₂ | ALPHAGAZ 2 H₂ | |
| Generator | |||
| Helium | ALPHAGAZ 1 He | ALPHAGAZ 2 He | |
| Nitrogen | ALPHAGAZ 1 N₂ | ALPHAGAZ 2 N₂ | |
| Generator | |||
| Anerobic digestion |
Hydrogen | ALPHAGAZ 1 H₂ | ALPHAGAZ 2 H₂ |
| Generator | |||
Helium ionisation detector (pulsed discharge), PD-HID
Gas quality for gas chromatography GC-PD-HID
See below the most suitable gas and purity for your analyzer:
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|---|---|---|---|---|
| Gas phase sample (mol/mol) | % | 0.1% | 0.01% | 10ppm | <1ppm |
Recommended gases :
| Carrier gas | Helium | ALPHAGAZ 2 He |
|---|---|---|
| Make-up | ALPHAGAZ 2 He | |
| Purging of the optics | ALPHAGAZ 1 He | |
| Landfill gas | ALPHAGAZ 2 He |
Photoionisation detector, PID
Gas Quality for GC-PID Gas Chromatography
See the most suitable gas and purity for your analyzer below:
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|---|---|---|---|---|
| Gas phase sample (mol/mol) | % | 0.1% | 0.01% | 10ppm | <1ppm |
Recommended gases :
| Carrier gas | Argon | ALPHAGAZ 1 Ar | ALPHAGAZ 2 Ar |
|---|---|---|---|
| Helium | ALPHAGAZ 1 He | ALPHAGAZ 2 He | |
| Nitrogen | ALPHAGAZ 1 N₂ | ALPHAGAZ 2 N₂ | |
| Generator | |||
| Hydrogen | ALPHAGAZ 1 H₂ | ALPHAGAZ 2 H₂ | |
| Generator | |||
| Make-up | Hydrogen | ALPHAGAZ 1 H₂ | ALPHAGAZ 2 H₂ |
| Generator | |||
| Argon | ALPHAGAZ 1 Ar | ALPHAGAZ 2 Ar | |
| Helium | ALPHAGAZ 1 He | ALPHAGAZ 2 He | |
| Nitrogen | ALPHAGAZ 1 N₂ | ALPHAGAZ 2 N₂ | |
| Generator | |||
Flame photometric detector, FPD
Gas Quality for GC-FPD Gas Chromatography
See below the most suitable gas and purity for your analyser:
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|---|---|---|---|---|
| Gas phase sample (mol/mol) | % | 0.1% | 0.01% | 10ppm | <1ppm |
Recommended gases :
| Carrier gas | Nitrogen | ALPHAGAZ 2 N₂ |
|---|---|---|
| Helium | ALPHAGAZ 2 He | |
| Make-up | Nitrogen | ALPHAGAZ AUTO IV N₂ |
| Helium | ALPHAGAZ 2 He | |
| Flame (Air) | Air | ALPHAGAZ 2 AIR |
| Flame (H₂) |
Hydrogen |
ALPHAGAZ 2 H₂ |
| Generator |
Nitrogen-Phosphorus or NPD detector
Gas Quality for GC-NPD Gas Chromatography
See below the most suitable gas and purity for your analysis:
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|---|---|---|---|---|
| Gas phase sample (mol/mol) | % | 0.1% | 0.01% | 10ppm | <1ppm |
Recommended gases :
| Carrier gas | Nitrogen | ALPHAGAZ 2 N₂ |
|---|---|---|
| Helium | ALPHAGAZ 2 He | |
| Make-up | Nitrogen | ALPHAGAZ 2 N₂ |
| Helium | ALPHAGAZ 2 He | |
| Flame (Air) | Air | ALPHAGAZ 2 AIR |
| Flame (H₂) |
Hydrogen |
ALPHAGAZ 2 H₂ |
| Generator |
Electrochemical detector, ELCD
Gas Quality for Gas Chromatography GC-ELCD
See below for the most suitable gas and purity for your analyser:
Meaurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|---|---|---|---|---|
| Gas phase sample (mol/mol) | % | 0.1% | 0.01% | 10ppm | <1ppm |
Recommended gases :
| Carrier gas | Waterstof | ALPHAGAZ 1 H₂ | ALPHAGAZ 2 H₂ |
|---|---|---|---|
| Generator | |||
| Stikstof | ALPHAGAZ 1 N₂ | ALPHAGAZ 2 N₂ | |
| Generator | |||
| Argon | ALPHAGAZ 1 Ar | ALPHAGAZ 2 Ar | |
| Helium | ALPHAGAZ 1 He | ALPHAGAZ 2 He | |
| Make-up | Helium | ALPHAGAZ 1 He | ALPHAGAZ 2 He |
| Hydrogen | ALPHAGAZ 1 H₂ | ALPHAGAZ 2 H₂ | |
| Generator | |||
|
Argon |
ALPHAGAZ 1 Ar | ALPHAGAZ 2 Ar | |
| Nitrogen | ALPHAGAZ 1 N₂ | ALPHAGAZ 2 N₂ | |
| Generator | |||
| Furnace (H₂) | Hydrogen | ALPHAGAZ 1 H₂ | ALPHAGAZ 2 H₂ |
| Generator | |||
| Oven (O₂) | Oxygen | ALPHAGAZ 1 O₂ | ALPHAGAZ 2 O₂ |
Supercritical extraction, SFE
Gas quality for supercritical phase chromatography, SFE
See below the most suitable gas and purity for your analyzer:
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|
Recommended gases :
| Mobile phase | Koolstofdioxide | ALPHAGAZ CO₂ SFC |
|---|
Methanizer
Gas quality for gas chromatography GC-Methanizer
Consult below the most suitable gas and purity for your analyzer:
Measurement range :
|
Sample in solution |
>g/L | 1g/L | 0.1g/L | 10mg/L | <1mg/L |
|---|---|---|---|---|---|
| Gas phase sample (mol/mol) | % | 0.1% | 0.01% | 10ppm | <1ppm |
Recommended gases :
| Process gas | Hydrogen | ALPHAGAZ 1 H₂ | ALPHAGAZ 2 H₂ |
|---|---|---|---|
| Generator | |||