[Theoretical analysis of the membrane transport non-homogeneous non-electrolyte solutions: influence of thermodynamic forces on thickness of concentration boundary layers for binary solutions]

Abstract

The nonlinear mathematical model equations for membrane transport of binary non-electrolyte solutions was presented. This model, the influence of the volume flows caused by simultaneous action of osmotic and hydraulic forces in concentration boundary layers creation, controlled by concentration Rayleigh number is taken into account. In a basis of obtained fourth order equations, the numerical calculations of concentration boundary layers thicknesses (delta(l) and delta(h)) for five variables: concentration (C(h)), hydrostatic pressure difference (deltaP), hydraulic permeability (L(p)), reflection (sigma), solute permeability (omega) coefficients and concentration Rayleigh number (R(c)) were performed. Characteristics obtained in the study show that external forces cause nonlinear increase or decrease of the concentration boundary layers thicknesses.