Abstract

Synthesis, Characterization and Electrochemical Properties of Composite Membrane by an Aqueous Sol-Gel Method

Fakhra Jabeen and M Sarfaraz Nawaz

The composite membranes were prepared by sol-gel process, and the membrane potential has been measured for characterizing the ion-transport phenomena across a charged membrane using electrolytes (KCl, NaCl and LiCl). The membrane potential offered by the electrolytes is in the order of LiCl>NaCl>KCl. The results have been used to estimate fixed-charge density, distribution coefficient, charge effectiveness and transport properties of electrolytes of this membrane. The fixed-charge density is the most important parameter, governing transport phenomena in membranes. It is estimated by the TMS method; it is dependent on the feed composition due to the preferential adsorption of some ions. The results indicate that the applied pressure is also an important variable to modify the charge density and, in turn, the performance of membrane. The experimental results for membrane potential are quite consistent with the theoretical prediction. The morphology of the membrane surface is studied by Scanning Electron Micrographs (SEM).