On the multi-component diffusion in the linear region of the extended thermodynamics framework

In this work, the application of axioms such as Onsager reciprocal relations (ORR) and the quasi-equilibrium axiom for multi-component diffusion in the linear region of extended thermodynamics is investigated. It is shown that the quasi-equilibrium axiom is a direct consequence of the Galilean invariance and the ORR are compatible with this principle. This allows the formulation of diffusion models such as the Onsager-Fuoss formalism and the Maxwell-Stefan model for the multi-component diffusion in the linear region of extended thermodynamics. Moreover, criteria for the detection of extrema in the entropy production rate for multi-component diffusion are proposed. It is believed that this work could be applied in processes such as the drying of glassy coatings.