Studies with inorganic precipitative membranes XI. Membrane potential response, characterization and evaluation of effective fixed charge density

Abstract

Membrane potentials arising across parchment supported nickel and cobalt phosphate membranes when they separete 1:1 electrolyte solutions of concentration c1 and c2 such that c1=10 c2, have been measured. The membranes in contactwith dilute solutions have been found to carry a negative charge whereas the charge reversal was observed when the membrane was separating concentrated solutions. The membrane potential data have been used according to the procedure prescribed by Teorell-Meyer-Sievers theory (the TMS theory) to derive the value of effective fixed charge density of membranes. The electrical double layer at the membrane-solution interface has been suggested to control the over all rate of diffusion.