Group-type quantitation of hydrocarbons in aviation fuel using GC×GC–FID

Significance of the topic

Detailed hydrocarbon profiling in aviation fuels ensures product quality and regulatory compliance, particularly important with new sustainable aviation fuels that require precise characterization of hydrocarbon classes.

Study objectives and overview

This study demonstrates a complete workflow for group-type quantitation of hydrocarbons in aviation fuel following ASTM D8396. Key aims:

• Validate reverse fill/flush modulation using the INSIGHT-Flow modulator
• Optimize separation of hydrocarbon classes with a custom column set
• Streamline data processing via ChromSpace software
• Enhance throughput using dual-channel GC×GC–FID configuration
• Offer a retrofit solution for existing GC systems

Methodology and instrumentation

Separation was achieved on a reverse phase column set according to ASTM D8396, employing a custom larger loop volume for improved class resolution. The INSIGHT-Flow flow modulator operated in reverse fill/flush mode with a modulation period of 7.8 s and adjustable loop volume (25–250 µL). GC×GC–FID analysis used hydrogen carrier gas and optimized temperature and flow conditions. Data acquisition and batch processing were handled by ChromSpace software using a stencil-based group analysis workflow.

Instrumentation

• Gas chromatograph configured for GC×GC with dual INSIGHT-Flow reverse fill/flush modulators
• ASTM D8396 reverse phase column set (OEM-SEP-COLKIT-10)
• Flame ionization detector with hydrogen carrier 50 mL/min, air 350 mL/min and makeup gas 5 mL/min at 300 °C
• ChromSpace software for instrument control and automated data processing

Main results and discussion

The method exhibited excellent class separation and high precision. Relative standard deviations of raw peak areas were below 2 %, and calculated mass percentages remained within 0.5 % of known values across ten replicates. The stencil workflow enabled automated classification and area percent reporting across multiple samples and instruments. Dual-channel analysis doubled sample throughput under unified software control.

Benefits and practical applications

• High precision and reproducibility for quality control of aviation and turbine fuels
• Rapid group-type quantitation suitable for high-throughput laboratories
• Compatibility with existing GC equipment through modular retrofit
• Scalable batch processing and standardized reporting across platforms

Future trends and opportunities

Increasing demand for sustainable aviation fuels will drive the need for advanced analysis methods. Potential developments include integration with alternative detectors, further automation of data workflows, and expansion of GC×GC applications to broader fuel matrices and environmental monitoring.

Conclusion

The presented GC×GC–FID workflow, leveraging reverse fill/flush modulation and stencil-based data processing, offers a robust and efficient approach for hydrocarbon group quantitation in aviation fuels. Its high accuracy, throughput, and retrofit capability support both current quality assurance needs and future analytical challenges in sustainable fuel development.