Determination of molecular diffusion coefficient in n-Alkane binary mixtures: empirical correlations

Abstract

In this work we have measured the molecular diffusion coefficient of the n-alkane binary series nCi-nC6, nCi-nC10, and nCi-nC12 at 298 K and 1 atm and a mass fraction of 0.5 by using the so-called sliding symmetric tubes technique. The results show that the diffusion coefficient at this concentration is proportional to the inverse viscosity of the mixture. In addition, we have also measured the diffusion coefficient of the systems nC12-nC6, nC12-nC7, and nC12-nC8 as a function of concentration. From the data obtained, it is shown that the diffusion coefficient of the n-alkane binary mixtures at any concentration can be calculated from the molecular weight of the components and the dynamic viscosity of the corresponding mixture at 50% mass fraction.