Simulated Distillation GC Analysis of Biodiesel Blends by ASTM D2887 Procedure B

Importance of the Topic

Gas chromatography methods that simulate conventional distillation have become essential for rapid characterization of fuel boiling point distributions. Accelerated techniques such as ASTM D2887 Procedure B enable efficient analysis of complex mixtures, including biodiesel blends, reducing analysis time and solvent consumption while maintaining accuracy. This capability is critical for quality control in fuel production, regulatory compliance, and development of renewable energy alternatives.

Objectives and Study Overview

This application note demonstrates the use of a Shimadzu Nexis GC-2030 system with accelerated ASTM D2887 Procedure B for simulated distillation of biodiesel blends. Key goals include:

• Evaluating system suitability and calibration using standard alkanes.
• Verifying distillation profiles of reference oils.
• Measuring and comparing distillation curves of biodiesel blends under different carrier gases.

Results highlight method robustness, reproducibility, and the impact of carrier gas choice on analytical performance.

Methodology and Instrumentation

The analytical procedure followed the accelerated ASTM D2887 Procedure B. Standard calibration solutions were prepared by diluting a 1 % w/w alkane mixture in carbon disulfide and a low-boiling point mixture separately to account for volatility losses. Key analytical conditions:

• Injection volume: 0.1 µL with solvent and sample wash cycles.
• Oven program: 100 °C (0.5 min) ramped at 35 °C/min to 350 °C (2 min).
• Carrier gas: helium at 37 mL/min (column flow mode), alternate runs with nitrogen.
• Detector: FID at 365 °C, makeup flow 0 mL/min, H₂ 32 mL/min, air 200 mL/min, filter time constant 100 ms.

Used Instrumentation

• Shimadzu Nexis GC-2030 (230 V)
• AOC-30i autoinjector with chilled syringe sequence
• High-temperature septa
• 0.5 µL NanoVolume on-column syringe
• FID-2030 detector with 0.5 mm nozzle
• SH-MXT-1 capillary column (7.5 m × 0.53 mm, 1.50 µm)
• LabSolutions GC and Simulated Distillation GC Analysis software

Key Results and Discussion

System suitability tests using the alkane standard showed resolution between C16 and C18 peaks of 8.0 (criteria 4–11), skewness within 0.8–1.3, and relative response factors (RRF) within 0.90–1.10. Reference oil checks confirmed temperature recoveries and repeatability met ASTM tolerances across 0.1–100 % distillation points. A diesel oil sample spiked with 20 % palm-derived biodiesel produced a reproducible distillation curve, matching predicted retention time–boiling point relationships.
Comparative tests using nitrogen as carrier gas yielded equivalent system suitability results, though slight shifts in retention and peak shape underscore the need for consistent gas selection and verification.

Benefits and Practical Applications

• Rapid, reliable boiling point distribution analysis of petroleum and renewable fuel mixtures.
• Centralized data management and reporting via LabSolutions software.
• Ability to accommodate alternative carrier gases for laboratories with varied gas supplies.
• Improved throughput for QA/QC in fuel production and regulatory laboratories.

Future Trends and Opportunities

Further advances may include integration of higher-throughput autosamplers, expanded software algorithms for complex mixtures, and coupling with mass spectrometry for structural identification of unknown components. The adoption of greener carrier gases or lower flow rates could reduce operational costs and environmental impact.

Conclusion

The Shimadzu Nexis GC-2030 platform, employing accelerated ASTM D2887 Procedure B and LabSolutions software, provides a robust solution for simulated distillation analysis of biodiesel blends. Method validation demonstrated compliance with system suitability and reference oil criteria, while comparative gas studies affirmed the approach’s flexibility. This workflow supports efficient quality control and characterization of renewable and petroleum-derived fuels.

References

No external literature references were cited.