Determination of sulfur-containing compounds, formaldehyde, and organic halides in hydrogen for proton-exchange membrane fuel cell vehicles

Importance of the topic

Hydrogen with low levels of sulfur compounds, formaldehyde, and halogenated organics is essential for reliable operation of proton-exchange membrane fuel cells. Trace impurities can poison catalysts, shorten service life, and impair performance, making precise analytical monitoring critical for hydrogen quality control in automotive applications.

Objectives and Study Overview

This application note presents a comprehensive analytical method compliant with GB/T 37244-2018 for quantifying sulfur-containing species, formaldehyde, and organic halides in hydrogen used for fuel cell vehicles. The workflow integrates thermal desorption preconcentration, gas chromatography with sulfur chemiluminescence detection (SCD), and single quadrupole mass spectrometry (MS) to evaluate calibration, detection limits, and repeatability against regulatory criteria.

Methodology and Instrumentation

• Sampling and Preconcentration: Inert canisters collected hydrogen samples, with impurities concentrated on the Markes UNITY–CIA Advantage-xr focusing trap by thermal desorption (up to 800 mL sampling volume).
• Chromatographic Separation: A Restek Rtx-1 column (60 m×0.32 mm×5 µm) provided baseline resolution and Gaussian peaks under a temperature program from 40 °C to 220 °C.
• Detection: The TRACE 1610 GC was equipped with an PAC SeNSe SCD for sulfur compounds and an ISQ 7610 single quadrupole MS for formaldehyde and organic halides in SIM mode, using a 3:1 split to each detector via a dual-detector microfluidic kit.

Main Results and Discussion

• Linearity: All analytes demonstrated linear responses (R² ≥ 0.995) over calibration ranges of 0.1–10 nmol/mol (sulfur species), 1–400 nmol/mol (formaldehyde), and 1–100 nmol/mol (organic halides), with response factor RSDs below 30 %.
• Limits of Detection: Calculated LODs (3.143×σ) were approximately 0.01 nmol/mol for sulfur compounds, ~0.04 nmol/mol for formaldehyde, and between 0.06 and 0.095 nmol/mol for organic halides, exceeding regulatory requirements.
• Repeatability: Peak area RSDs were below 5 % for sulfur compounds and below 3.2 % for formaldehyde and organic halides (n=7 injections), confirming method precision.

Benefits and Practical Applications

The combined thermal desorption–GC–SCD/MS approach offers high sensitivity, selectivity, and full automation, making it ideal for routine quality assurance of hydrogen fuel. It ensures compliance with Chinese standards and protects fuel cell catalysts, supporting long-term performance in automotive PEMFC systems.

Future Trends and Opportunities for Use

• Real-time or on-line impurity monitoring at hydrogen refueling stations.
• Integration with high-resolution MS or advanced detectors for broader analyte coverage and lower detection limits.
• Adaptation to other fuel cell technologies and industrial hydrogen streams.
• Development of portable TD–GC systems for field deployment and rapid screening.

Conclusion

The validated analytical workflow meets or surpasses GB/T 37244-2018 requirements for trace sulfur compounds, formaldehyde, and organic halides in hydrogen. Its robust sensitivity, precision, and ease of automation provide a reliable tool for protecting PEM fuel cell performance and extending operational lifetime.

Reference

1. GB/T 37244-2018 Fuel specification for proton exchange membrane fuel cell vehicles – Hydrogen and group standard.
2. T/CECA-G 0180-2022 Determination of sulfur-containing compounds, formaldehyde, and organic halides in hydrogen – Preconcentration/GC–SCD and MS detection method.
3. GB/T 44243-2024 Hydrogen for proton exchange membrane fuel cell vehicles – Determination of sulfur compounds, formaldehyde and organic halides – GC method.