Advantages and Disadvantages of Substitution of Helium as Carrier Gas in Gas Chromatography by Hydrogen. Part I. – Technical and Safety Aspects

Significance of the Topic

The choice of carrier gas in gas chromatography critically influences analysis speed, resolution and reproducibility, especially in flavor and quality testing in brewing. Recent helium shortages and price increases drive laboratories to consider hydrogen as an alternative carrier gas.

Objectives and Overview

This paper reviews the technical requirements and safety considerations for substituting helium with hydrogen in gas chromatography systems. It examines gas sourcing, system modifications and risk management.

Methodology and Instrumentation

A review of gas production methods: helium is obtained by cryogenic distillation of natural gas while hydrogen can be generated from steam reforming or water electrolysis. Options for supply include high-pressure cylinders and on-site generators. Modern GCs with electronic pressure control and flame ionization detectors monitor flow, pressure and leaks, providing automatic shutdown in fault conditions.

Main Results and Discussion

• Hydrogen offers faster analysis, higher sensitivity and improved peak resolution compared to helium or nitrogen.
• Safety risks of hydrogen’s flammability are mitigated by small gas volumes in generators, in-oven detectors and robust stainless steel tubing.
• Generators reduce dependency on cylinders and simplify laboratory logistics, though nitrogen generators require compressed air.
• Switching carrier gas often necessitates replacing copper tubing to prevent brittleness and contamination.

Benefits and Practical Applications

• Cost savings due to lower hydrogen price and elimination of helium cylinder rentals.
• Environmental advantage since hydrogen can be produced from water without depleting scarce resources.
• Reliable availability prevents analysis interruptions associated with helium shortages.

Future Trends and Possibilities

• Wider adoption of hydrogen generators and GC systems optimized for hydrogen.
• Development of enhanced safety features, such as improved in-oven sensors and automatic cut-offs.
• Research into alternative carrier gases and hybrid approaches to reduce helium reliance.

Conclusion

Under proper technical setup and safety protocols, hydrogen is a viable and sustainable alternative to helium as a GC carrier gas, offering economic, environmental and analytical benefits.

References

Bartram R. J., Froehlich P., 2010: Considerations on switching from helium to hydrogen. LCGC North America 10:1–8.
Chromacademy online: Translating GC methods from helium to hydrogen carrier gas.
Parker online: Pressure Swing Adsorption nitrogen generators.
Peak Scientific online: Gas generator specifications.
Labicom online: Hydrogen generator details.
Linde-gas online: High-purity gas supply.
Chromservis online: Nitrogen generators.
European Brewery Convention, 2005: Analytica EBC methods.
The Institute of Brewing, 1997: IOB methods of analysis.
The American Society of Brewing Chemists, 2009: ASBC methods of analysis.