Simultaneous Analysis of Greenhouse Gases Using Nitrogen Carrier Gas

Importance of the Topic

Monitoring and quantifying greenhouse gases such as CO2, CH4 and N2O is critical for assessing emission sources and tracking progress toward carbon neutrality. Analytical methods that combine sensitivity, precision and simplified hardware are essential for laboratories and field research engaged in environmental quality control.

Objectives and Study Overview

This study demonstrates a gas chromatography approach using a single Nexis GC-2030 system to perform simultaneous analysis of CO2, CH4 and N2O. By integrating a Jetanizer™ flame ionization detector (FID) and an electron capture detector (ECD) with nitrogen carrier gas, the method aims to simplify instrumentation and maintain robust analytical performance across a wide concentration range.

Methodology and Instrumentation

Samples are introduced via an MGS-2030 gas sampler with a 1 mL loop under split-injection conditions. A two-way capillary adapter feeds two micro-packed columns in parallel. The Jetanizer replaces the FID nozzle to enable CO2 detection. A fixed flow of N2 (5 mL/min) serves as carrier gas. Thermal programs and detector gas flows are optimized for baseline separation over a 30-minute run time.

Used Instrumentation

• Nexis GC-2030 with split injection
• MGS-2030 gas sampler (1 mL loop)
• Jetanizer™ FID adaptor
• ECD-2010 Exceed with Ar+5%CH4 as detection gas
• Micro-packed ST columns (2 m × 1 mm I.D.)

Main Results and Discussion

Calibration across 1–100 ppm CH4, 10–1000 ppm CO2 and 0.05–2.5 ppm N2O showed excellent linearity (R2 > 0.999). Ambient air samples yielded repeatability (%RSD) below 1.1 for CH4, 0.4 for CO2 and 0.6 for N2O. Long-term stability tests under repeated air pressurization confirmed that Ar+5% CH4 as ECD gas maintained sensitivity and repeatability (<0.5% RSD), whereas pure N2 caused signal drift.

Benefits and Practical Applications

• Simultaneous detection of three major greenhouse gases on a single GC platform
• Elimination of helium carrier simplifies logistics and reduces operating costs
• Sufficient sensitivity for trace-level atmospheric monitoring and process control
• Stable long-term performance supports continuous or high-throughput analysis

Future Trends and Applications

Integration with automated sampling systems and remote monitoring platforms can further streamline field deployments. Advances in detector miniaturization and data analytics will enable real-time emission mapping. Coupling this approach with isotopic analysis or high-resolution columns may expand capabilities to source attribution and speciation studies.

Conclusion

The described method offers a robust, cost-effective solution for simultaneous quantification of CO2, CH4 and N2O using nitrogen carrier gas. The combination of Jetanizer-FID and ECD provides high linearity, repeatability and long-term stability, making it well suited for research, regulatory and industrial applications.

References

Uchiyama S. Simultaneous Analysis of Greenhouse Gases Using Nitrogen Carrier Gas. Shimadzu Application News No. 01-00661-EN, Dec. 2023.