SO2 diffusion through acetonitrile-saturated perfluorosulfonic acid membranes

Abstract

The diffusion coefficient of SO2 and acetonitrile in Nafion perfluorinated ion exchange membranes have been determined from chromatographic measurements of SO2 concentration and the isotopic ratios in acetonitrile solutions. The diffusion coefficients vary with residual water content and attain values about one fifth those reported for water-saturated membranes falling in the range 1–2 × 10−7 cm2 s−1. Values obtained for Teflon reinforced material indicates diffusion takes place over an effective surface more than twice the optically open area.