The Maxwell-Stefan approach to mass transfer

Molecular Simulations of Zeolites: Adsorption, Diffusion, and Shape Selectivity

“…D c is called the collective, corrected, or Maxwell-Stefan diffusion coefficient. 131 In an NMR experiment, a different diffusion coefficient is measured. In a so-called pulse field gradient (PFG-NMR) experiment, one labels a particle and the attenuation of the signal is directly related to the self-diffusion coefficient (D s ).…”

“…Here, we give a compact introduction; a more complete description can be found in the excellent book by Kärger and Ruthven 252 or in several reviews. 28,131 To link the Maxwell-Stefan diffusion coefficient to the transport diffusion coefficient, we need to convert a gradient of the concentration into a gradient of the chemical potential. For this, let us define a thermodynamic correction factor Γ…”

Nanofluidic transport governed by the liquid/vapour interface

“…We derived a modified transmission probability (η eff ) using the dusty-gas model that is widely employed for gas flow through porous media [35][36][37] . The model accounts for interaction among gas molecules as well with the pore wall, and has been experimentally verified for binary 38 and ternary 39 gas mixtures under conditions varying from Knudsen to viscous regimes.…”

Comparison of modeling methods for the determination of effective porosities and diffusion coefficients in through‐diffusion tests

“…It is recognized, however, that Fick's law has limitations. As noted by Krishna and Wesselingh [1997], Fick's law is strictly valid for the following conditions: (1) diffusion in binary mixtures or (2) diffusion of a species in dilute multispecies solutions and (3) diffusion in the absence of electrostatic or centrifugal force fields. Lacking these conditions, diffusion of a species will be impacted by forces exerted by other species in the multispecies solution, or by external forces (e.g., electrostatic) if present.…”