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

Abstract

Dynamic responses of self-made potentiometric NH 3 , CO 2 , and SO 2 sensitive gas sensors are followed in the 10 ‫5מ‬ -5 ‫ן‬ 10 ‫3מ‬ M concentration range. By least squares fitting of potential versus time curves, Dk product values at the diffusion of NH 3 , CO 2 , and SO 2 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 CO 2 and SO 2 with the CO 2 sensitive sensor indicate the presence of the interferent.