Trace Impurity Analysis of Hydrogen Fuel in Fuel Cell Vehicle-Related Fields

Significance of the topic

Fuel cells powered by hydrogen require extremely high purity to avoid catalyst poisoning by carbon monoxide.
ISO 14687-2 sets stringent impurity limits, including a maximum of 0.2 ppm CO.
Conventional impurity analysis often relies on complex multi-column and multi-detector setups, increasing cost and maintenance.
Advances in barrier discharge ionization detection (BID) enable more sensitive, streamlined gas chromatography for trace analysis of hydrogen fuel impurities.

Objective and study overview

This study aims to demonstrate high-sensitivity detection of carbon monoxide and simultaneous analysis of multiple gaseous impurities in hydrogen fuel cell applications using a single GC system equipped with BID.
The work is divided into two approaches:

• High-sensitivity CO quantification on an Rt-Msieve 5A column
• Simultaneous multi-component analysis including CO2 on a Micropacked ST column

Methodology

A standard gas mixture of trace impurities was diluted in hydrogen to approximately 0.2 ppm for each component.
Two chromatographic methods were implemented:

• Rt-Msieve 5A column for high-resolution separation of CO from air components
• Micropacked ST column for concurrent detection of CO, CO2, N2O, hydrocarbons, and air gases

Instrumentation

• Shimadzu Tracera GC-2010 Plus with BID-2010 Plus detector
• RESTEK Rt-Msieve 5A column (30 m × 0.53 mm I.D., 50 µm df) with Particle Trap
• Micropacked ST column (2 m × 1 mm I.D.)
• MGS-2010 manual gas sampler with SPLITTER-INJ injection unit

Main results and discussion

On the Rt-Msieve 5A column, the CO detection limit was 0.032 ppm (S/N = 3) with clear separation from O2 and N2.
Using the Micropacked ST column, simultaneous detection of CO (LOD 0.078 ppm), CH4, CO2, N2O, C2H2, C2H4, and C2H6 was achieved, meeting ISO 14687-2 requirements.
The BID detector demonstrated higher sensitivity and broader component coverage compared to TCD and FID.

Benefits and practical applications

This approach reduces system complexity by consolidating multiple analyses into a single GC-BID platform.
It ensures regulatory compliance while lowering operating costs and maintenance burdens.
Laboratories in research, QA/QC, and industrial sectors can implement this method for efficient hydrogen fuel purity monitoring.

Future trends and potential applications

Automation of sample handling and data processing may enable real-time monitoring of hydrogen quality.
Extending BID-based GC to other fuel gases or environmental analyses could expand its utility.
Ongoing detector enhancements may further lower detection limits and simplify instrument upkeep.

Conclusion

The integration of BID in gas chromatography provides a sensitive, versatile solution for trace impurity analysis in hydrogen fuel.
Specialized columns allow both targeted and multi-component analyses to satisfy ISO 14687-2 in a single system.
This streamlined method offers a cost-effective alternative to traditional multi-system configurations, supporting the advancement of hydrogen fuel cell technology.