Simulated Distillation of Petroleum Products (ASTM D2887) by GC in less than two minutes

Importance of the Topic

The boiling range distribution of petroleum fractions is a critical parameter for refining control, quality assurance and specification testing. Simulated distillation by gas chromatography (SimDist GC) offers faster and more detailed insights into boiling point profiles compared to classical ASTM distillation, supporting more efficient process monitoring in petrochemical laboratories.

Objectives and Study Overview

This application note presents a rapid SimDist GC method for petroleum products following ASTM D2887. The aim was to demonstrate that Ultra Fast GC (UFGC) equipped with direct resistive heating can perform full boiling range analyses in under two minutes while maintaining ASTM compliance, precision and accuracy.

Methodology and Instrumentation

Instruments and configuration:

• Thermo Trace GC system fitted with Ultra Fast Module (UFM) for direct resistive heating
• Fused silica capillary column, 5 m length, 0.32 mm internal diameter, 0.1 μm film thickness
• Fast flame ionization detector (Fast FID) heated to 350 °C
• Injector in split mode at 280 °C
• SimdiChrom software optimized for 10 ms data slices

Method:

• Calibration with n-alkane mixture (C6–C44) under the same temperature program
• Temperature ramp from 40 °C (12 s) to 350 °C (18 s) at 5 °C/s
• Automatic oven fan cooling from 350 °C to 40 °C in approximately one minute

Main Results and Discussion

Calibration repeatability over ten injections showed retention time standard deviations below 0.05 s and peak area RSDs under 1.7 %. Boiling point distribution for ASTM D2887 reference oil matched conventional GC results within 1–2 °C across 0.5 % to 99.5 % volume cuts. The total run time was less than two minutes, roughly 20 times faster than standard SimDist protocols.

Benefits and Practical Applications

This Ultra Fast GC SimDist approach enables:

• Rapid turnaround for high-throughput petrochemical laboratories
• Full compliance with ASTM D2887 requirements
• Improved sample throughput without sacrificing precision or accuracy
• Streamlined QC for refining operations and specification testing

Future Trends and Possibilities

Further miniaturization of capillary modules and advances in data processing will push heating rates beyond 20 °C/s and reduce analysis time below one minute. Integration with automated sampling and cloud-based data analytics can deliver real-time boiling range monitoring and predictive maintenance in refinery workflows.

Conclusion

Direct resistive heating in Ultra Fast GC provides a validated, ASTM-compliant SimDist method that reduces analysis time by a factor of 20 while maintaining excellent repeatability and agreement with reference data. This technology represents a significant improvement for routine petroleum product characterization.

Reference

1. ASTM D2887 Standard Test Method for Boiling Range Distribution of Petroleum Fractions by Gas Chromatography