Preparation of cupric palmitate membrane, its characterization and evaluation of thermodynamically effective fixed charge density.

Membrane potentials have been measured across parchment-supported cupric palmitate membrane separating various 1:1 electrolytes at concentrations C1 and C2 such that C2 = 10 C1. Membrane potential data have been used to calculate transference number of ions, permselectivity and also to derive the thermodynamically effective fixed charge density which is an important characteristic governing the membrane phenomena by utilizing the generally accepted and most widely used theory of Teorell-Meyer and Sievers as well as the recent theories for membrane potential of Kobatake et al. and Nagasawa et al. based on the principles of nonequilibrium thermodynamics. The values of charge densities derived from different theories were almost the same, confirming thereby the validity of the recently developed theories of membrane potential.