Mutual diffusion coefficients of dimethyl carbonate + n-heptane and dimethyl carbonate + isooctane from 288.15 K to 318.15 K

Abstract

The mutual diffusion coefficients of dimethyl carbonate + n-heptane and dimethyl carbonate + isooctane binary systems were measured at temperatures from 288.15 K to 318.15 K with the mass fraction of dimethyl carbonate from 0.05 to 0.95 under atmospheric pressure. All the mutual diffusion coefficients we reported are Fick diffusion coefficients, which were measured by the digital holographic interferometry. The expanded relative uncertainty for the measured mutual diffusion coefficients is estimated to 2.4% with the level of confidence of 0.95 (coverage factor k = 2). Moreover, a theoretical model (UNIDIF) of mutual diffusion coefficients for dimethyl carbonate + n-heptane and dimethyl carbonate + isooctane binary mixtures was given by fitting the experimental results, and the adjustable parameters and infinite dilution diffusion coefficients of these two solutions were given. The influences of temperature and composition on the mutual diffusion coefficients were discussed.