Synthesis of poly-styrene based nickel phosphate membrane : Evaluation of membrane parameters and to test the membrane potential theories

Abstract

The fabrication of polystyrene-based nickel phosphate membranes at different pressures with varying amounts of material has been described. In order to understand the mechanism of transport of ions and to evaluate various membrane parameters controlling the transport phenomena, the membrane potential measurements were carried out using different concentrations of 1: 1 electrolytes solutions. Teorell-Meyer and Sievers (TMS) method was used for the estimation of memhrane parameter in the form of thermodynamically effective fixed charged density of membranes. The data were then utilized to calculate theoretical membrane potential values using extended TMS theory. Bi-ionic potential (BIP) measurements were reported keeping the same concentration of ionic species on the two sides of the membranes. On the other hand, Toyoshima and Nozaki method was used for the evaluation of theoretical values of bi-ionic potential (BIP) at the same concentration of ionic species on two sides of the membrane, utilizing the membrane parameters evaluated using the values of membrane potential. The close agreement between theoretical and observed values in both cases not only proved the existance of the membrane but also confirm the applicability to examine the validity of the theory utilized to the membrane electrolyte systems. Scanning electron microscope (SEM) monographs of the membrane have also been presented.