Halogenated hydrocarbons - Analysis of impurities in 1,2-dichloroethane

Importance of the topic

Monitoring trace halogenated hydrocarbons in 1,2-dichloroethane is vital for ensuring product quality, process safety and environmental compliance in chemical manufacturing. Impurities such as low-molecular-weight chlorinated compounds can impact downstream reactions, pose health hazards and influence regulatory approval of end-use products.

Objectives and overview

This study demonstrates a robust gas chromatographic–mass spectrometric method for rapid, sensitive detection and quantification of volatile halogenated impurities in 1,2-dichloroethane using an Agilent PoraBOND U porous polymer column. The goal is to achieve baseline separation of key contaminants under isothermal conditions with minimal column bleed and high operational stability.

Methodology and instrumentation

• Technique: Capillary gas chromatography with mass spectrometric detection (GC-MS).
• Column: Agilent PoraBOND U, 0.32 mm × 25 m, 7 µm porous layer open tubular (PLOT).
• Temperature: Isothermal run at 30 °C.
• Carrier gas: Helium at 50 kPa (0.5 bar).
• Injector: Split mode 1:30, 250 °C.
• Detector: Mass selective detector at 250 °C.
• Sample: 0.5 µL injection of 500 ppm standard mixture.

Main results and discussion

• Nine volatile analytes were fully resolved within a single isothermal run:
  
  1. Air
  2. Carbon dioxide
  3. Water
  4. Methyl chloride
  5. Vinyl chloride
  6. Chloroethane
  7. 1,1-Dichloroethylene
  8. 1,2-Dichloroethane
  9. Aromatic compounds
• Excellent peak shapes and minimal tailing were observed for all chlorinated species.
• Column stability was confirmed at 300 °C with low baseline bleed, supporting long-term routine use.
• Mass spectral detection enabled unambiguous identification and quantification at sub-ppm levels.

Benefits and practical applications

• Rapid screening of feedstocks and final products in chemical manufacturing.
• Quality control for compliance with environmental and safety standards.
• High throughput analysis with minimal temperature programming simplifies operation.
• Robust column chemistry reduces downtime and maintenance.

Future trends and possibilities

• Integration with automated high-throughput sampling for real-time process monitoring.
• Coupling with multidimensional GC or tandem MS for enhanced selectivity of complex mixtures.
• Adoption of machine-learning algorithms for automated peak recognition and quantitation.
• Development of more inert, low-bleed stationary phases to expand the temperature range and analyte scope.

Conclusion

This application note establishes a reliable, isothermal GC-MS method for comprehensive analysis of halogenated impurities in 1,2-dichloroethane. The Agilent PoraBOND U column offers superior stability, peak performance and low bleed, making it an ideal choice for routine quality control and environmental monitoring.

References

• Agilent Technologies, Inc. Application Note A01588: Halogenated hydrocarbons – Analysis of impurities in 1,2-dichloroethane. First published May 2010; printed October 2011.