Local Composition Based Maxwell-Stefan Diffusivity Model for Binary Liquid Systems

A new model for predicting Maxwell-Stefan diffusivity of binary mixture is developed based on the local composition concept and Eyring's Absolute reaction rate theory. The proposed model, extended from the Vignes equation, can predict the mutual diffusion coefficient based on the diffusivities at infinite dilution and the local volume fractions calculated by Wilson model. Diffusivities of nine binary systems are used to compare the proposed model with three available models. The diffusivities of five systems among the nine are measured experimentally in the present work with digital holographic interferometry. The comparison showed that this model was superior to the Vignes model for all systems and competed well with the other models.