Helium remains the most popular carrier gas for gas chromatography. It is also the second most abundant element in the universe and, yet, there are concerns being raised that available stocks will disappear within the next few years. It is therefore incumbent upon us as gas chromatographers to take a responsible attitude regarding helium usage.
In this paper, we will review the ways helium is consumed by GCs and the costs associated with this. We explore techniques to reduce helium consumption through sophisticated leak detection systems and simple adjustments to standard GC methods.
We also consider the implications of changing GC methods to use alternative gases such as hydrogen or nitrogen.
One of the major objections in changing from helium as a carrier gas is that the chromatography of a given sample on a given column will change. In practice this need not be the case and we will show that by applying the same linear gas velocity, the same chromatography may be closely reproduced with any carrier gas.
To address this need, we have developed programmable pneumatic control systems capable of maintaining a set carrier gas velocity through a given column. We have applied this technology to the chromatography of samples using different carrier gases and have been able to demonstrate the expected reproducibility.
We feel that a few simple actions on the part of the GC user can significantly reduce GC operating costs and help preserve this valuable natural resource without impacting the quality of the analytical data being generated.
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