There are many online resources that suggest “preferred equipment” and “best practices” to help laboratory managers when they source supplies and accessories for their workplace.
Laboratories regularly performing gas chromatography (GC) testing require carrier gas to feed their equipment. However, with the availability of several carrier gas options, it can become tricky to quickly identify the particular option to fit a particular need.
Lab managers looking for carrier gas should first address two key questions:
- Delivered gas vs. on-site gas generators – which is appropriate?
- Helium vs. hydrogen vs. nitrogen – which is preferable?
Delivered Gas Versus On-site Gas Generators
Labs are different. Some of them need several gas chromatographs to satisfy the demand of their testing. More gas is needed if the number of equipment is more. However, buying bottled gases also brings in attendant hassles. Apart from being cumbersome and costly, users opting for delivered gases make their laboratories vulnerable to purity discrepancies, price hikes, asphyxiation risks, and safety.
On-site gas generators are a safe and reliable solution to provide high purity nitrogen and hydrogen gases for GCMS carrier and FID applications. On-site gas generators generate the needed gas at the time of its requirement with nil inventories. This eases the risks related to storing bottled gases. When on-site gas generators are used, the time spent on swapping cylinders is saved, and the laboratory does not get cluttered with gas cylinders. Hassles commonly seen with bottled gas price volatility and supply disruptions are lessened. A reliable gas generator poses no disruption of lab operations and allows testing to be conducted in a worry-free manner.
Helium Versus Hydrogen Versus Nitrogen
In gas chromatography, three choices of carrier gas are available: helium, hydrogen, and nitrogen. Without doubt, helium is an excellent carrier gas for gas chromatography applications, and delivers quick results and requires little-to-no adjustment to equipment. However, the gas is expensive.
Hydrogen can be substituted for helium in many applications. It delivers quicker results than helium, and the laboratory staff can achieve the same accuracy by making minor adjustments to equipment. Since using bottled hydrogen is risky, on-site hydrogen gas generators produce the gas based on the demand, thus making the equipment the most effective solution to source carrier gas.
Some GC testing can be performed by using nitrogen as well. In such cases, the laboratory staff should adjust the column, so that the equipment can make use of nitrogen. Since nitrogen gas is slower as compared to helium and hydrogen, it takes that much longer time to obtain the test results. Although nitrogen is very affordable, the gas is not compatible with all GC test methods.
Now You Know
Each laboratory is different, but options are available for using carrier gas. During the evaluation of a carrier gas, the following points need to be taken into account: equipment gas demand, testing methods, purity requirements, and laboratory size.
This information has been sourced, reviewed and adapted from materials provided by Proton OnSite
For more information on this source, please visit Proton OnSite