On-line analysis of NH3, CO2, and SO2 diffusion through microporous Teflon

Dynamic responses of self-made potentiometric NH₃, CO₂, and SO₂ sensitive gas sensors are followed in the 10⁻⁵–5 × 10⁻³M concentration range. By least squares fitting of potential versus time curves, Dk product values at the diffusion of NH₃, CO₂, and SO₂ through microporous Teflon are calculated. The obtained results are fairly reflected by the behavior of the sensor. Measurements of potential versus time in mixed solutions of CO₂ and SO₂ with the CO₂ sensitive sensor indicate the presence of the interferent. © 1999 John Wiley & Sons, Inc. Lab Robotics and Automation 11: 224–228, 1999