(237e) A Zeolite-Assisted Microwave Planar Resonator Sensor for Non-Contact Quantification of CO2 and CH4 in Gas Streams

Gas sensing and analysis by monitoring the dielectric properties of the adsorbent materials is an emerging, robust, sensitive, and inexpensive technique with contactless operation capability. Planar resonator sensors are particularly favored for this purpose due to their simple structure and operation principle. In this study, a zeolite 13x-assisted planar microwave microstrip resonator sensor, reinforced by regenerative feedback loop, was investigated for CO₂ and CH₄ detection. Real-time monitoring was performed when the sensor was exposed to 1 % to 50% gas concentrations. The sensing was completed by detecting the adsorbents permittivity change during adsorption of the target gases on zeolite 13x. The change in the permittivity was due to the cumulative effect of increased temperature (heat of adsorption) and occupied pores of the adsorbents. By correlating the resonant frequency shift with the concentration of the target gas, the sensor was able to detect CO₂ and CH₄.