Aromatics in Light Naphtha and Aviation Gasolines - ASTM 2267

Significance of the Topic

Accurate quantification of aromatic hydrocarbons in light naphtha and aviation gasoline is essential for ensuring fuel quality, meeting regulatory requirements and optimizing performance. Gas chromatography with flame ionization detection (GC-FID) following ASTM D2267 provides reliable separation and quantitation of key aromatic components that influence octane rating, emission profile and downstream processing.

Objectives and Study Overview

This application note describes a capillary GC method for the simultaneous analysis of nine aromatic and related hydrocarbons in light naphtha and aviation gasoline. The primary goals are:

• To achieve baseline resolution of target analytes.
• To establish a robust temperature program and flow conditions.
• To comply with ASTM D2267 requirements for routine quality control.

Methodology and Used Instrumentation

The separation was performed on a cyanopropyl methylpolysiloxane capillary column (60 m × 0.25 mm I.D. × 0.25 µm film thickness, Cat. No. 007-23-60-0.25F). Chromatographic conditions:

• Temperature program: 60 °C initial hold for 3.0 min; ramp at 10 °C/min to 260 °C.
• Injector temperature: 250 °C.
• Detector (FID) temperature: 300 °C.
• Carrier gas: Helium at a linear velocity of 25.3 cm/s.

Main Results and Discussion

The method provided clear separation of nine compounds with distinct retention times increasing according to molecular weight and polarity. Detected analytes include:

• Decane
• Benzene
• Undecane
• Toluene
• Cumene
• m-Xylene and Ethylbenzene
• p-Xylene
• o-Xylene
• 1,2,4-Trimethylbenzene

Baseline resolution was achieved for all targets, and the FID response demonstrated high sensitivity and linearity across the fuel matrix. Repeatability met industry standards for routine QC analysis.

Benefits and Practical Applications

This GC-FID approach offers:

• Rapid analysis with total run time under 30 minutes.
• Robust performance suitable for high-throughput labs.
• Compliance with ASTM D2267 for quality assurance in petrochemical and aviation fuel industries.
• Capability to monitor product consistency, detect adulteration and support octane optimization.

Future Trends and Opportunities

Emerging enhancements may include coupling capillary GC with mass spectrometry for confirmatory identification, utilization of shorter high-efficiency columns to reduce analysis time, integration of automated sample preparation and advanced data analytics for real-time process monitoring. Adoption of green chromatography practices and alternative carrier gases may also broaden sustainability in routine fuel testing.

Conclusion

The described GC-FID method delivers precise, reproducible analysis of key aromatic hydrocarbons in light naphtha and aviation gasoline. Its alignment with ASTM D2267 ensures reliable quality control and supports critical decision-making in fuel production and compliance.

Reference

ASTM D2267 – Standard Test Method for Aromatics in Light Naphtha and Gasoline by Gas Chromatography