Amino alcohols - Analysis of ethanol amines

Importance of the Topic

Ethanol amines are polar analytes with critical roles in environmental and industrial contexts. Accurate quantification of mono-, di-, and triethanolamine is essential for process control, environmental monitoring, and compliance with regulatory limits. Conventional capillary GC faces challenges in elution and detection of these compounds at trace levels due to strong interactions and potential column bleed.

Objectives and Study Overview

This study demonstrates the performance of a dedicated GC stationary phase (Agilent CP-Sil 8 CB for Amines) for the separation and quantification of ethanol amines at nanogram levels. The note outlines the analytical strategy for achieving sharp peaks, low detection limits, and robust operation over a wide temperature range.

Methodology and Instrumentation

• Analytical Technique: Gas chromatography with flame ionization detection (GC-FID).
• Column: Agilent CP-Sil 8 CB for Amines, fused silica WCOT, 0.32 mm × 30 m, df = 1.0 µm.
• Temperature Program: Initial 60 °C (5 min), ramp at 6 °C/min to 220 °C.
• Carrier Gas: Hydrogen at 50 kPa (0.5 bar).
• Injector Conditions: Split mode at 270 °C.
• Detector Conditions: FID at 300 °C.
• Calibration Range: 5–10 ng per component.
• Sample Preparation: Methanol as solvent.

Main Results and Discussion

The specialized stationary phase achieved baseline separation of MEA, DEA, and TEA with sharp peaks at lower oven temperatures. The column’s temperature stability up to 325 °C enabled rapid bake-out, minimizing carryover and extending column life. Detection at nanogram levels was readily achieved with minimal background interference.

Benefits and Practical Applications

• Enhanced sensitivity for environmental and process monitoring.
• Improved peak shape reduces quantification errors.
• Broad temperature tolerance enables analysis of diverse amine mixtures.
• Reduced column aging from bake-out extends maintenance intervals.

Future Trends and Potential Uses

Ongoing developments in GC stationary phases and detector technologies aim to lower detection limits further and increase throughput. Integration with mass spectrometry could offer additional specificity for complex matrices. Automation of sample preparation and coupling with real-time data analytics will enhance routine monitoring in environmental and industrial laboratories.

Conclusion

The Agilent CP-Sil 8 CB for Amines column provides a reliable solution for trace analysis of ethanol amines by GC-FID, combining low detection limits, robust performance, and operational flexibility. This method supports precise monitoring in environmental and industrial applications.

Reference

Agilent Technologies, Inc. Amino alcohols: Analysis of ethanol amines. Application Note A01538, October 31, 2011.