Examples of Analyzing Organic Compound Species with Hydrogen Carrier Gas Using Nexis GC-2030

Importance of the topic

Gas chromatography is a key analytical technique for volatile organic compounds. Using hydrogen as a carrier gas can significantly reduce operational costs and improve analysis speed compared to helium, but introduces flammability concerns. The Nexis GC-2030 addresses these safety issues with an integrated hydrogen sensor that monitors oven gas concentration and triggers protective actions when thresholds are exceeded.

Objectives and study overview

This application note demonstrates hydrogen carrier gas performance on the Nexis GC-2030 through two example analyses. The first evaluates separation of ten organic analytes on a polar capillary column. The second showcases high-efficiency solvent analysis on a narrow-bore column, examining retention, repeatability, and pressure requirements under hydrogen and helium conditions.

Methodology and instrumentation

• Instrument: Nexis GC-2030 with AOC-20i autosampler and hydrogen concentration sensor
• Carrier gas: Hydrogen or helium, constant column flow mode
• Detectors: Flame ionization detector with H2 at 32 mL/min, air at 200 mL/min; makeup gas N2 or He at 24 mL/min
• Columns: SH-StabiliWAX (30 m × 0.32 mm ID, 0.50 μm) for Example 1; SH-Rtx-WAX narrow-bore (20 m × 0.10 mm ID, 0.10 μm) for Example 2
• Injection: Split mode, 0.5 μL injection, split ratio 1:50 (1:100 in Example 2), injector temperature 260 °C
• Oven programs: Example 1 – 50 °C (2 min), ramp 10 °C/min to 200 °C; Example 2 – 40 °C, ramp 4 °C/min to 50 °C, hold 1 min, ramp 40 °C/min to 90 °C

Main results and discussion

Example 1 achieved equivalent separation with significantly shorter run times when using hydrogen, owing to a higher optimal linear velocity (54.1 cm/s vs 45.3 cm/s), while resolution remained at approximately 1.9 for critical peak pairs. Example 2 benefited from hydrogen’s lower viscosity, enabling operation of a narrow-bore column at reduced inlet pressures (371.5 kPa vs 594.7 kPa) and high linear velocity (55.4 cm/s). Five replicate injections yielded area RSDs below 1.2% and retention time RSDs below 0.02%, demonstrating excellent reproducibility.

Benefits and practical applications

• Cost savings by replacing helium with hydrogen
• Faster analysis through higher carrier gas velocities
• Improved separation efficiency on narrow-bore columns
• High reproducibility suitable for QA/QC and research labs

Future trends and applications

Integration of hydrogen generators and advanced safety sensors will further facilitate hydrogen-based GC methods. Anticipated growth areas include environmental analysis, petrochemical monitoring, and pharmaceutical quality control. Development of ultra-low-dead-volume columns will continue to enhance speed, sensitivity, and resolution.

Conclusion

The Nexis GC-2030’s built-in hydrogen sensor provides essential safety monitoring that enables routine use of hydrogen as a carrier gas. The examples presented confirm that hydrogen delivers faster separations, lower operating pressures, and robust repeatability, positioning it as a viable, cost-efficient alternative to helium in diverse GC applications.

Instrumentation used

• Nexis GC-2030 gas chromatograph with AOC-20i autosampler
• Integrated hydrogen concentration sensor
• Hydrogen flame ionization detector (FID)