Simulation of S-entropy production during the transport of non-electrolyte solutions in the double-membrane system

Abstract

Using the classical Kedem-Katchalsky' membrane transport theory, a mathematical model was developed and the original concentration volume flux (J(v)), solute flux (J(s)) characteristics, and S-entropy production by J(v), ((psi S)Jv) and by J(s) ((psi S)Js) in a double-membrane system were simulated. In this system, M-1 and M-r membranes separated the l, m, and r compartments containing homogeneous solutions of one non-electrolytic substance. The compartment m consists of the infinitesimal layer of solution and its volume fulfills the condition V-m -> 0. The volume of compartments l and r fulfills the condition V-l = V-r -> infinity. At the initial moment, the concentrations of the solution in the cell satisfy the condition C-l < C-m < C-r. Based on this model, for fixed values of transport parameters of membranes (i.e., the reflection (sigma(l), sigma(r)), hydraulic permeability (L-pl, L-pr), and solute permeability (omega(l), omega(r)) coefficients), the original dependencies C-m = f(C-l - C-r), J(v) = f(C-l - C-r), J(s) = f(C-l - C-r), (psi S)Jv = f(C-l - C-r), (psi S)Js = f(C-l - C-r), R-v = f(C-l - C-r), and R-s = f(C-l - C-r) were calculated. Each of the obtained features was specially arranged as a pair of parabola, hyperbola, or other complex curves.