Industrial Applications with a New Polyethylene Glycol-Based GC Column

Importance of the Topic

Polyethylene glycol (PEG)-based GC columns are essential for separating polar analytes but often suffer from active site interactions that cause peak tailing, adsorption losses, and reduced sensitivity. Enhancing column inertness is critical for reliable, reproducible analysis in demanding industrial and environmental applications, including alcohols, aldehydes, acids, phenols, and other reactive compounds.

Objectives and Overview of the Study

This application note evaluates the novel Agilent J&W DB-WAX Ultra Inert capillary column. The primary goals are to assess its chromatographic efficiency, chemical inertness, hydrolysis resistance, and lifetime compared to traditional PEG phases, using multiple challenging test mixtures.

Methodology and Instrumentation

An Agilent 7890A+ GC with an Agilent 7693 autosampler and FID detector was employed. Key conditions included:

• Column: 20 m × 0.18 mm, 0.3 µm Ultra Inert PEG phase
• Carrier gas: Hydrogen, constant flow at 28 cm/s
• Inlet: Split/splitless at 250 °C, split ratio 25:1, ultra inert liner
• Oven program: 40 °C (1 min) to 250 °C at 20 °C/min

Test samples comprised a hydrocarbon calibration mix (C10–C32), polar ISO column mix, Grob test mix, chlorinated hydrocarbons in process water, phenolic antioxidants in fuels, nonradioactive fuel markers, and volatile organics. Aqueous injection stability was probed by interleaving 1 µL water injections up to 150 times.

Main Results and Discussion

• Hydrocarbon Range: C10–C32 hydrocarbons produced sharp, symmetrical peaks, demonstrating high phase efficiency.
• Polar ISO Mix: Alcohols, ketones, phenols, and basic compounds (e.g., aniline) showed well-defined peaks with minimal tailing.
• Grob Test Mix: Highly active analytes such as dicyclohexylamine and 2-ethylhexanoic acid exhibited excellent resolution and peak shape.
• Aqueous Injection Stability: No retention time drift or peak degradation after 150 consecutive water injections, indicating robust resistance to hydrolysis and swelling.
• Chlorinated Hydrocarbons in Process Water: Five organochlorines were quantified with sharp peaks, important for environmental monitoring.
• Phenolic Antioxidants: Eight phenols commonly found in fuels and lubricants were separated with high repeatability and consistent symmetry.
• Fuel Marker Compounds: Butylphenyl ether, dimethoxybenzene, and trimethoxybenzene yielded reproducible, symmetrical peaks, critical for anti-counterfeiting markers.
• Volatile Organic Compounds: Trace levels (0.5–1 ppm) of light hydrocarbons and acetaldehyde were detected with minimal tailing, supporting accurate quantification.

Benefits and Practical Applications

• Superior Inertness: Minimizes interactions across a wide polarity range.
• Direct Aqueous Injection: Eliminates complex sample preparation for water-based matrices.
• Versatile Utility: Applicable in environmental, petrochemical, food, and pharmaceutical industries.
• Compatibility with Multidimensional GC: Offers phase orthogonality for GC×GC separations.
• Increased Column Lifetime: Enhanced robustness reduces downtime and cost.

Future Trends and Applications

Ongoing developments in stationary phase chemistry and surface deactivation will further improve column inertness and thermal stability. Integration with high-speed two-dimensional GC and hyphenation to mass spectrometry will expand capabilities in metabolomics, trace-level environmental analysis, and real-time industrial process monitoring.

Conclusion

The Agilent J&W DB-WAX Ultra Inert GC column delivers exceptional inertness, stability, and efficiency for both polar and nonpolar analytes. Its resistance to hydrolysis, direct aqueous injection capability, and consistent performance across challenging test mixtures make it a versatile solution for high-demand industrial and environmental analyses.

References

1. Dang N.; Vickers A. K. A New PEG GC Column with Improved Inertness Reliability and Column Lifetime; Agilent Technologies, Inc., 2016.
2. Zou Y. Lavender Oil Analysis Using Agilent J&W DB-WAX Ultra Inert Capillary GC Columns; Agilent Technologies, Inc., 2016.
3. Zou Y. GC Analysis of Glycols in Toothpaste; Agilent Technologies, Inc., 2016.
4. Lynam K.; Zou Y. Analysis of Distilled Spirits Using Agilent J&W DB-WAX Ultra Inert Capillary GC Column; Agilent Technologies, Inc., 2016.
5. Luong J.; Gras R.; Shellie P. Piston-Cylinder-Based Micro Liquid-Liquid Extraction with GC-qMS for Trace Analysis of Targeted Chlorinated Compounds in Water. Canadian Journal of Chemistry 2015, 93(11), 1283–1289.