Hydrocarbon Analysis of Reference Standard for Impurities in 1,3 butadiene for ASTM method

Importance of the topic

The reliable detection and quantification of trace hydrocarbon impurities in 1,3-butadiene is essential for ensuring product quality, process safety and compliance with regulatory standards. Impurities can interfere with polymerization, catalyst performance and end-use applications, making robust analytical methods a cornerstone of industrial and research laboratories.

Study objectives and overview

This application note presents an ASTM-compliant approach to characterize a reference standard containing 26 hydrocarbon impurities in 1,3-butadiene. The study demonstrates chromatographic separation, peak identification and quantitation of light hydrocarbons (C2–C6) including alkanes, alkenes, alkynes and aromatics using gas chromatography with flame ionization detection (GC-FID).

Used instrumentation

• Gas chromatograph: SCION GC with FID detector
• Injector: Large-volume split (LSV) 1:10 000, injection volume 1 µL
• Column: SCION Al₂O₃, 50 m × 0.32 mm, 5 µm film thickness
• Oven program: 40 °C (6 min hold) ramped at 5 °C/min to 160 °C
• Carrier gas: Helium at 75 kPa
• Detector: FID at 250 °C

Methodology

The reference standard was injected under split conditions to minimize overload while maintaining sensitivity. The alumina column provided high selectivity for C–C bond types. A temperature ramp ensured sequential elution from low-boiling acetylene to higher boiling aromatics such as benzene and toluene. Peak identities were confirmed by retention time matching against known standards.

Main results and discussion

Baseline separation was achieved for all 26 target compounds, ranging from acetylene and cyclopropane to 1,3-butadiene and toluene. Retention times were reproducible with relative standard deviations below 1 %. The FID response was linear across the calibration range, supporting accurate quantitation. The alumina column demonstrated robustness through multiple runs with no significant shifts in retention.

Benefits and practical applications

This GC-FID method offers:

• High sensitivity for trace-level hydrocarbon detection
• Robust separation of isomeric alkenes and alkynes
• Rapid analysis compatible with routine QA/QC workflows
• Compliance with ASTM specifications for 1,3-butadiene impurity profiling

Future trends and opportunities

Advancements that could further enhance hydrocarbon impurity analysis include:

• Coupling GC with mass spectrometry for added specificity and structural confirmation
• Implementation of fast-GC columns and temperature programming for reduced run times
• Automated sample handling and data processing using chemometric tools
• Extension of the method to real-time process monitoring and environmental emissions testing

Conclusion

The described GC-FID procedure with an alumina column delivers reliable, reproducible separation and quantitation of diverse hydrocarbon impurities in 1,3-butadiene. Its adherence to ASTM guidelines makes it a valuable asset for industrial laboratories focused on product quality control and regulatory compliance.