CH₄/C₂H₆ dual gas sensing system using a single mid-infrared laser.

Area of Science:

• Analytical Chemistry
• Environmental Science
• Sensor Technology

Background:

• Accurate simultaneous detection of methane (CH4) and ethane (C2H6) is crucial for environmental monitoring and industrial safety.
• Existing dual gas sensors often suffer from cross-interference and system complexity, limiting their practical application.

Purpose of the Study:

• To develop a low-complexity, high-stability dual gas sensor for simultaneous detection of CH4 and C2H6.
• To implement a correction method for eliminating cross-interference between CH4 and C2H6.
• To validate the sensor's accuracy, response speed, and long-term stability.

Main Methods:

• Development of a dual gas sensor system with reduced complexity.
• Application of an absorbance spectrum-based correction method to mitigate cross-interference.
• Linear fitting for single gas concentration measurements (CH4 and C2H6).
• Continuous and long-term measurements of mixed gas samples.

Main Results:

• Achieved high accuracy with correlation coefficients R² = 0.99959 for CH4 and R² = 0.99994 for C2H6.
• Successfully eliminated cross-interference of C2H6 on CH4 detection.
• Demonstrated fast response speed and strong stability through continuous and long-term measurements.
• Attained minimum detectable column densities of 0.62 ppm·m for CH4 and 0.1 ppm·m for C2H6.

Conclusions:

• The proposed CH4/C2H6 dual gas sensor, enhanced by a spectral correction method, offers high sensitivity and robustness.
• The sensor system exhibits excellent stability and minimal cross-interference, making it suitable for diverse applications.
• This technology holds significant potential for accurate and reliable environmental and industrial gas monitoring.