P—V—T data and virial coefficients for gaseous methane—water mixtures with correction for adsorption effects

Abstract

Precise experimental P—ϱ— T measurements for 10, 25, and 50 mole per cent water in methane mixtures were obtained using a Burnett—Isochoric (B—I) apparatus. These data are vapor—phase measurements at temperatures from 398.15 K to 498.15 K and pressures of 72 kPa to 12.03 MPa or the dew point pressure at each temperature. In the analysis of these data, we have corrected for the effects of H 2O adsorption on the measured pressures using a Brunauer—Emmett—Teller (BET) adsorption model and applicable BET adsorption constants. This analysis yielded precise values of compressibility factors, densities, and mixture and interaction virial coefficients. The densities are believed to be accurate to within 8/10,000 and the mixture second virial coefficients to ± 2 cm 3/mol. Additionally, dew point pressures were determined for each mixture by calculating the point of slope change in the vapor isochores.