Fabrication and Electrochemical Characterization of Polyvinyl Chloride-Co- Polyethylene Glycol Based Heterogeneous Cation Exchange Membranes for the Application in Electrodialysis Process

In this research, the effect of blending polyvinylchloride/polyethylene glycol on Physico-chemical and separation characteristics of heterogeneous cation exchange membranes was studied. Heterogeneous cation exchange membranes were prepared by using the phase inversion method through the solution casting technique. Obtained results showed that membrane water content and surface hydrophilicity were enhanced by an increase of PEG ratio in the membrane matrix. The membrane ion exchange capacity, charge density, membrane potential, transport number, and selectivity initially were improved by the use of PEG concentration up to 4 %wt in membrane matrix and then began to decrease by more PEG ratio from 4 to 16 %wt. The membrane ionic permeability and flux were enhanced initially by an increase of PEG content ratio up to 2 %wt in membrane matrix and then showed decreasing trend by more PEG loading ratio from 2 to 8 %wt. The ionic permeability and flux were enhanced again by more increase of PEG concentration from 8 to 16 %wt. The membrane areal electrical resistance was decreased sharply by the use of PEG in the membrane matrix. The membrane transport number and selectivity were also increased by an increase in electrolyte concentration. Membrane showed higher transport number and selectivity at neutral pH compared to other pH values. Results show that the modified membrane in this study is comparable with that of commercial membranes.