Specialty Gas Mixtures

Specialty gas mixtures and certified multi component calibration gas mixtures used   for research, analysis and control. They enable calibration of laboratory equipment and on-line analysers, gas detectors,  chromatography equipment, moisture analyzers or FTIR spectrometeres and more.

In general an analytical method is a comparative method.  Consequently, the final result of the analysis depends on the reliability of calibration gases used. To perform multi-point calibration, linearity checks, LOQ/LOD validation laboratories or process analyzer services have to keep significant stock of the standard gas cylinders with calibration gas mixtures at various concentrations and compositions.

The inconvenience is that gas standards in cylinders are expensive to order and delivery times are long. As well large gas cylinder stock  is restrictive from a security point of view.

To save money and gain in flexibility, many laboratories use GasMix ™  precise dynamic gas mixers/diluters.

Indeed, a  single bottle of  high/ average grade and a diluent gas are needed to produce unlimited concentrations, which drastically reduces the stock of bottles.

Moreover, the validity of a standard gas is an important issue. Most low levels bottles certificates offer 6 months to 1 year validity. Thus, to meet the quality, it will renew often, even if the bottle is not empty. A standard mix at high concentration will have a longer life (3 years as a rule). The user will then have the opportunity  using the diluter to  produce on-site low level concentrations at his choice with very little added uncertainty.

In addition, GasMix ™ optimizes the consumption of gas by doing automatically cut the gas when needed.

Application examples:

Reduction of a standard gas cylinder stock

One customer, a manufacturer of gas analyzers, had a large gas cylinders stock. To calibrate their devices in full range a compound should be present in 6 different concentrations in a balance gas, for example:

• • CO2 – 100ppm
  • CO2 – 5000ppm
  • CO2 – 5%
  • CO2 – 25%
  • CO2 – 50%
  • CO2 – 100%

The list of test compounds is among others contained: CH4, CO, NO, NO2, SO2, N2O.
In order to reduce the stock of bottles, the company has acquired one of our diluters. So, with GasMix™, their stock of bottles decreased from 42 to 12 cylinders !

Generation of on-demand gas mixture and transfert it using a tedlar bag

Dynamic diluters allow a large quantity of the gas mixture to be prepared on a continuous basis and that multicomponent mixtures can be prepared as readily as binary mixtures with little added uncertainty. This practical solution is easy to put in place in an analytical laboratory significantly reducing the stock of cylinders of calibration gases .

Dynamic gas mixers/diluters GasMix™ deliver the desired concentration of gas in the output line that is typically directly connected to an analyser like GC, spectrometer, or a reactor for analysis, for an experiment, or a calibration purpose.

Sometimes it is not possible to link the diluter directly (like a GC without a GSV) . The user can transfer a gas by a sampling bag (e.g. Tedlar bag) or a capacity. The gas mixture is collected and future injected into an analyzer by a gas tight syringe or other mean.
To make this transfer properly we can give you some tips. Read more