Simple Group-Type Analyses of Aviation Fuels

Importance of Topic

Group-type analysis provides detailed insight into the hydrocarbon composition of aviation fuels. This information is vital for predicting fuel behavior, energy content and stability under operating conditions, especially as sustainable alternative fuels (SAF) gain traction in the aviation sector.

Objectives and Study Overview

The study aims to demonstrate the capabilities of flow-modulated two-dimensional gas chromatography with flame ionization detection (GCxGC-FID) for group-type analysis of aviation fuels. Two samples are compared: a conventional Aviation Reference Fuel and a Fischer-Tropsch Synthetic Paraffinic Kerosene (FT-SPK).

Used Instrumentation

• GCxGC system: LECO Paradigm GCxGC
• Modulation: Flow modulation between first and second dimensions
• Columns: Polar phase in the first dimension, non-polar phase in the second dimension
• Detection: Flame ionization detector (FID)

Methodology

A reverse-phase configuration (polar first dimension, non-polar second dimension) enhances separation of hydrocarbon classes. Flow modulation allows heart-cutting between GC dimensions without cryogenics. The FID provides quantitative group-type distribution.

Key Results and Discussion

Analysis reveals distinct hydrocarbon distributions:

• Aviation Reference Fuel contains approximately 21.4% normal paraffins, 24.4% isoparaffins, 32.9% naphthenes, 19.1% monoaromatics and 2.1% polyaromatics
• FT-SPK is dominated by 75.3% normal paraffins, with 5.0% isoparaffins, 18.5% naphthenes and trace aromatics (0.3% monoaromatics)

These differences highlight the impact of synthesis routes on fuel composition and performance properties.

Practical Benefits and Applications

• High-accuracy group-type analysis for product specification and quality control
• Supports certification and performance evaluation of emerging SAF
• Cost-effective alternative to more complex detection systems

Future Trends and Applications

Advancements may include integration with mass spectrometry for structural identification, automated data processing with chemometric tools and expanded use of GCxGC-FID to characterize a broader range of sustainable fuels and bio-derived blends.

Conclusion

Flow-modulated GCxGC-FID using a reverse-phase configuration offers an efficient and robust approach for detailed group-type analysis of aviation fuels. It distinguishes conventional and synthetic fuels with high resolution and can aid the development and approval of sustainable alternatives.

References

• LECO Corporation 2023 Form No 209-200-175 Application Snapshot Group-Type Analyses of Aviation Fuels