Humidity influence in application of µGC-Systems for ethylene gas with preconcentrator devices and SnO2 based detectors

A new ethylene detector based on a SnO₂ gas sensor combined with a humidity/temperature sensor was applied in a novel μGC system for ethylene measurement with air as carrier gas. The used μGC column shows HETP values between 0.8 mm and 2 mm for carrier gas flow velocities between 2 cm/s and 40 cm/s. The humidity/temperature sensor in the detector allows the recognition of humidity induced peaks and fluctuations of the baseline in the chromatogram after preconcentrator desorption process. This is an important aspect when a preconcentrator is used as sample device together with metal oxide gas sensors during ethylene concentration measurement.