Ballooning helium costs keeping you up at night? Try Hydrogen and Nitrogen as Alternative Carrier Gases

Significance of the topic

The global scarcity and rising cost of helium present a critical challenge for gas chromatography (GC) and related analytical applications. Reliable carrier gas is essential for reproducible separations in research, quality control, petrochemical analysis and medical imaging support. Exploring hydrogen and nitrogen as alternative carrier gases can mitigate dependence on helium and reduce operating costs.

Objectives and overview of the study

This article reviews strategies for conserving helium and migrating existing GC methods to hydrogen (H2) or nitrogen (N2) carrier gases, based on an Agilent application webinar. Key goals include:

• Introducing programmable Gas Saver and Sleep/Wake modes to minimize idle helium use
• Providing a decision tree to guide chemists in selecting or switching carrier gases
• Describing best practices for method translation to H2 or N2 while preserving chromatographic performance
• Highlighting safety and performance considerations when using hydrogen, especially with mass spectrometry detectors

Used Instrumentation

• Agilent 7890B, 8860 and 8890 GC systems equipped with Mass Selective Detector (MSD) options
• Programmable Helium Conservation Module utilizing 5th generation auxiliary electronic pressure controller (EPC)
• Hydrogen generators (e.g., Parker H-MD) and high-purity H2 cylinders paired with Gas Clean filters
• Gas flow restrictors, three-way stream selection valves for manual switching
• Leak detector G3388B and optional H2 sensor for safety monitoring

Methodology and instruments

The Helium Conservation Module is integrated into GC hardware and software, automatically switching carrier supply to nitrogen standby during idle periods and reverting to helium on wake. Gas Saver mode in inlet methods lowers split flow during injections. For method migration, holdup time (retention factor) is maintained by adjusting column flow or pressure to match original helium retention times, guided by Van Deemter theory. Agilent’s method translation software, embedded in OpenLab CDS or as a Windows 7 utility, assists in converting pressure, flow and temperature programs for H2 or N2 carriers.

Main results and discussion

Implementation of Gas Saver and the conservation module can reduce helium consumption by over 80%, extending cylinder life from two to twelve months in an ASTM D4815 ethanol-in-gasoline test. GC/FID performance and chromatography remained unchanged after overnight nitrogen standby. MSD tuning passed within 15 minutes after switching back to helium. Migration cases demonstrated that maintaining original holdup time yielded peak retention times within 0.2% of helium standards for both hydrogen and nitrogen. Nitrogen provided “good enough” resolution for monoglyceride analysis (ASTM D6584) and two-dimensional GC for oxygenate and aromatic profiling (ASTM D4815) without method revalidation. Hydrogen offered speed gains but introduced potential reactivity and background noise in MSD systems, necessitating thorough safety and analytical validation.

Benefits and practical applications

• Significant cost savings and extended helium usage through automated conservation features
• Minimal method revalidation by preserving key chromatographic parameters during gas switch
• Broad applicability to routine GC, GC/MS and two-dimensional separations in environmental, petrochemical and QA/QC laboratories
• Enhanced safety and compliance via integrated gas-switching controls and pressure monitoring

Future Trends and Applications

Further integration of automated carrier gas management, expansion of method translation algorithms in chromatography software, and deployment of advanced safety sensors for hydrogen handling are expected. The adoption of nitrogen in two-dimensional GC workflows and optimized hydrogen generators with ultra-low contaminants will broaden alternative-gas usage. Ongoing research into inert gas mixtures and dynamic flow programming may yield new approaches to high-efficiency separations without helium.

Conclusion

By leveraging programmable conservation modules, method translation tools and a clear decision framework, analytical laboratories can substantially reduce helium dependence. Nitrogen often serves as a practical, low-risk alternative with minimal chromatographic compromise, while hydrogen offers speed advantages in selected applications when safety and analytical validation are carefully managed. These strategies collectively address helium availability challenges and enable more sustainable GC operations.