Ion-partitioning effects on electrokinetic flow of generalized Maxwell fluids through polyelectrolyte layer-coated nanopore under AC electric field

The article dealt with an analytic study on the electroosmotic flow and mass transport of an electro neutral solute through polyelectrolyte layer (PEL)-coated canonical nanopore under the imposed alternative current electric field for Maxwell fluids. The PEL of uniform thickness contains positive charge density, while surface potential of nanopore is negatively charged. The permittivities of the electrolyte solution and PEL are assumed to be different which creates the ion-partitioning effects. The Born formula is incorporated to account the ion-partitioning effects. For low surface charge, the distribution of the ionic species are governed by the modified Boltzmann distribution and using the Debye–Hückel approximation, linearized Poisson–Boltzmann equation gives the distribution of induce potential inside and outside of the PEL. The modified Cauchy momentum equation with the Maxwell constitutive equation is used for the fluid flow distribution interior and exterior of the PEL. The analytic solutions for the distribution of induced potential and axial velocity are established using modified Bessel function for the Maxwell fluid. The importance of the bulk ionic concentration, oscillating Reynolds number, PEL fixed charge density, relaxation time, permittivity ratio between PEL and electrolyte solution and softness parameter is studied in this investigation. The convection–diffusion equation is considered to transport of neutral solute between two reservoirs, connected with nanopore. An analytic solution for the distribution of solute concentration is also presented. The effects of the flow characteristics on volumetric flow rate, average mass transport, and neutralization factor are described in this study.