Helium has always been a prized resource, sealed in caverns filled with the gas to create the Helium National Reserves. However in 1996, legislation (1) allowed the sale of 0.6 billion ft3 of helium gas from 2005 to 2015. The price of crude helium set by the law was approximately $43/1000 scf.
In 2010, the price was reset by the Federal Bureau of Land Management to $64.75/1000 scf based on the Consumer Price Index (2). The price was again reset to $75.75/1000 scf for the financial year 2012. According to critics, the revised price is still very low when assessing the remaining reserves of helium. (3)
Helium is commonly used as a carrier gas for gas chromatography (GC). As it is becoming increasingly expensive, chromatographers prefer to use hydrogen, an inexpensive and reliable gas source.
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In addition to the economic issues around employing helium as a carrier gas in GC, there is a question of efficiency. For GC applications, both hydrogen and helium are highly efficient carrier gases, but there is a difference in the efficiency of the separation due to the differences in their properties.
The van Deemter equation predicts an optimum velocity at which there will be the minimum variance per unit column length, and as a result, a maximum efficiency. (4) Using this equation, it is possible to deduce that hydrogen can exhibit a higher linear flow rate than helium and deliver equal efficiency in the ability of the gas to separate peaks.
This information has been sourced, reviewed and adapted from materials provided by Proton OnSite.
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