Preparation and characterization of ion-selective polyvinyl chloride based heterogeneous cation exchange membrane modified by magnetic iron–nickel oxide nanoparticles

Abstract

In this research, polyvinylchloride/styrene–butadiene-rubber blend heterogeneous cation exchange membranes were prepared by solution casting technique using tetrahydrofuran as solvent and cation exchange resin powder as functional groups agent. Iron–nickel oxide (Fe 2NiO 4) nanoparticle was also employed as additive in membrane fabrication. The effect of additive concentration on properties of home-made membranes was studied. SOM images showed uniform particles distribution and relatively uniform surfaces for the membranes. The increase of Fe 2NiO 4 concentration in casting solution caused to decrease of membrane water content. Membrane ion exchange capacity initially was increased by additive increasing to 1 wt.% and then showed decreasing trend with higher additive content. Membrane potential, charge density, permselectivity and transport number were enhanced initially by increase of additive loading to 2 wt.% and then they began to decrease by more additive concentration. Membranes exhibited lower potential, selectivity and transport number for bivalent ions compared to monovalent ones. Membrane permeability, flux and conductivity were enhanced initially in monovalent ionic solution by increase in additive concentration to 0.5 wt.% and then began to decrease by more additive loading. Permeability was improved for bivalent ions with increase in additive concentration. Modified membranes showed higher permeability for bivalent ions compared to monovalent type.