Total Hydrocarbon Impurity Analysis in PEM Fuel Cell Grade Hydrogen Using the Agilent 8890 GC-FID System

Significance of the Topic

High-purity hydrogen for proton exchange membrane (PEM) fuel cells demands tight control of total hydrocarbon (THC) impurities to ensure cell performance and longevity. Analytical methods capable of accurately quantifying trace hydrocarbons are essential for quality assurance along the hydrogen supply chain.

Objectives and Study Overview

This study presents a rapid GC-FID approach using the Agilent 8890 system to measure THC in PEM fuel cell grade hydrogen. Methane is quantified separately by a micro GC method and subtracted to yield nonmethane THC.

Methodology and Instrumentation

The Agilent 8890 GC-FID is configured with a gas sampling valve, split/splitless inlet, uncoated capillary column (10 m × 320 µm), and flame ionization detector. Hydrogen carrier gas, a 0.25 mL sample loop, and a 40:1 split ratio enable injection of a fixed volume. Key parameters:

• Oven program: 40 °C (3.5 min), ramp at 30 °C/min to 180 °C
• Carrier gas flow: 2 mL/min
• FID gases: air 400 mL/min, H₂ 30 mL/min, N₂ makeup 25 mL/min

Methane measurement uses the Agilent 990 Micro GC with μTCD.

Key Results and Discussion

Hydrocarbons elute as a single peak at 0.5 minutes without column retention, facilitating total THC quantitation via the methane response factor. Hydrogen blanks show no interference in the retention window. Precision tests yielded repeatability of 2.09% (n=8) and reproducibility of 2.12% (n=16) over 20 days. Accuracy averaged 102.3% at 10 ppm and 111% at 2 ppm. The method detection limit (MDL) is 0.97 ppm, meeting the 2 ppm nonmethane THC specification in SAE J2719 and ISO 14687.

Benefits and Practical Applications

• Fast single-peak analysis reduces runtime and data processing.
• High precision and low MDL support routine QA/QC in fuel cell hydrogen production and distribution.
• Separate methane measurement ensures compliance with nonmethane THC limits.

Future Trends and Opportunities

Advances may include integrated multi-channel GC systems for simultaneous methane and THC analysis, on-line process monitoring, and extension to additional impurity classes such as sulfur- or halogen-containing compounds.

Conclusion

The presented GC-FID method provides a robust, accurate, and repeatable approach for total hydrocarbon analysis in PEM fuel cell grade hydrogen. It satisfies key regulatory standards and enhances operational efficiency in hydrogen quality control.

Instrumentation Used

• Agilent 8890 Gas Chromatograph with FID and uncoated capillary column
• Agilent 990 Micro Gas Chromatograph with micro thermal conductivity detector

References

• GB/T 44238-2024, Hydrogen for Proton Exchange Membrane Fuel Cell Vehicles—Determination of Total Hydrocarbons by Gas Chromatography.
• Coleman S. et al., Micro GC Analysis of Permanent Gas Impurities in PEM Fuel Cell Grade Hydrogen, Agilent Technologies Application Note 5994-8830EN, 2025.
• Zhang J., Helium, Argon, Nitrogen, and Hydrocarbon Impurity Analysis in Hydrogen Using an Agilent 8890 GC and TCD/FID System, Agilent Technologies Application Note 5994-7590EN, 2024.