High Sensitive CO, CO2, CH4 Analysis Nexis GC-2030CCC5 GC-2014CCC5

Importance of the Topic

Trace-level measurement of carbon monoxide, carbon dioxide and methane in oxygen matrices is essential for industrial process control, environmental monitoring and safety assessment. Accurate quantification of these gases supports compliance with regulatory limits, optimizes combustion processes and ensures the integrity of high-purity oxygen applications.

Objectives and Study Overview

This work presents a dedicated gas chromatographic system designed for sensitive analysis of CO, CO2 and CH4 in oxygen gas samples. The primary aim is to achieve reliable separation, low detection limits and rapid turnaround by integrating specialized columns, valve switching and a methanizer-FID detection scheme.

Methodology

The sample is introduced via an automated 10-port valve. A Porapak-N pre-column first retains high-boiling hydrocarbons and water, while oxygen and target analytes progress. A second valve directs oxygen through a waste line using cutting technology to protect the methanizer catalyst. CO and CH4 are separated on an MS-13X packed column; CO2 elutes through Porapak-Q. Both streams pass a methanizer, converting CO and CO2 to methane before detection by flame ionization (FID). Total runtime is approximately 13 minutes per injection.

Used Instrumentation

• Nexis GC-2030CCC5 gas chromatograph system
• 10-port and 6-port switching valves for sample introduction and oxygen removal
• Porapak-N pre-column, Porapak-Q separation column, MS-13X packed column
• Methanizer unit coupled to flame ionization detector (FID)
• LabSolutions GC workstation software for data acquisition and control

Main Results and Discussion

The system demonstrates linear quantification of CO, CO2 and CH4 from 1.0 to 100 ppm with detection limits near 1 ppm. Chromatograms show clear resolution of CO2 (eluting early), CH4 (mid-runtime) and CO (late-runtime) within a 13-minute analysis window. Oxygen removal via valve switching effectively protects the methanizer catalyst, maintaining stable sensitivity over repeated runs.

Benefits and Practical Applications

• High sensitivity and selectivity for trace CO, CO2 and CH4 in oxygen matrices
• Efficient matrix removal and backflush to extend column and catalyst life
• Single-channel configuration simplifies maintenance and operation
• Rapid analysis suitable for QA/QC laboratories and process monitoring

Future Trends and Opportunities

Advances may include integration of micro-GC modules for field deployment, adoption of alternative catalyst materials to further enhance methanizer lifetime, and coupling with real-time data analytics for predictive process control. Development of ultra-fast separations and miniaturized detection platforms could expand applications in environmental surveillance and on-site safety assessments.

Conclusion

The described GC-based approach provides a robust, sensitive and rapid solution for simultaneous analysis of CO, CO2 and CH4 in oxygen. Its streamlined valve switching and methanizer-FID configuration ensure reliable performance, making it well suited for industrial and environmental laboratories requiring precise trace gas determinations.

Reference

Shimadzu Corporation. Application Note SGC-ADS-0021A, First Edition, November 2017.