Facilitated transport of monovalent salt mixture through ultrafiltration Na-Mordenite membrane: Numerical investigations of electric and dielectric contributions

In this paper, a knowledge model is used to describe the rejection of ionic solutions: pure monovalent salt–water solutions and four halide ions–water mixture. This model is based on a description of the transport within the pores via the extended Nernst–Planck equation. Electric and dielectric contributions on the separation selectivity are investigated from experimental results. The first version of the numerical model, based on Donnan Steric Pore Model, cannot be used to simulate the experimental curves obtained with the mixture of halide monovalent salts. Then, the introduction of ion energy hydrations in the model to describe the dielectric contribution of each ion, which are proportional to the polarizability of ions, is necessary to adapt the model. This result confirms the contribution of Van der Waals forces in the rejection process observed.

► Investigation of facilitated transport of monovalent salt–water solutions.
► Numerical estimations of electrical and dielectrical contributions.
► New model development to account for the different dielectric contributions.