Structural and mathematical models for pressure-dependent electrodiffusion of an electrolyte through heterogeneous ion-exchange membranes: Pressure-dependent electrodiffusion of NaOH through the MA-41 anion-exchange membrane

Structural and mathematical models are proposed for describing electrolyte transport through heterogeneous anion-exchange membranes under conditions of pressure-dependent electrodiffusion. The idea that mesopores and macropores are present in the membrane provides the basis for the structural model. The Nernst-Planck equations with a convective term are used to describe ion transport in the solution filling the pores. Results of the solution to the mathematical problem and the experimental investigations demonstrate the possibility of decreasing the transport numbers of sodium ions through an anion-exchange membrane by applying a pressure gradient in the same direction as the electrolyte diffusion flux in the membrane.