Mixed matrix heterogeneous cation exchange membranes were prepared by solution casting technique. Ilmenite-co-iron oxide nanoparticle was also employed as inorganic filler additive in membrane fabrication. The effect of the used additives on membrane electrochemical properties was studied. Membrane ion exchange capacity, membrane potential, transport number and selectivity all were improved by use of FeTiO3/Fe3O4 nanoparticles in membrane matrix. Utilizing FeTiO3-co-Fe3O4 nanoparticles in the casting solution also led to increase in ionic flux obviously. The modified membranes containing FeTiO3-co-Fe3O4 nanoparticles showed higher transport number, selectivity and ionic flux compared to modified membrane containing ilmenite. Electrodialysis experiment in laboratory scale also showed higher cation removal for modified membrane containing FeTiO3-co-Fe3O4 nanoparticles compared to other modified membranes and pristine ones. Results showed that membrane areal electrical resistance declined sharply by use of FeTiO3-co-Fe3O4 nanoparticles in membrane matrix. Moreover, modified membrane containing ilmenite showed lower electrical resistance compared to others. Results showed that oxidative stability of membranes was decreased slightly by use of FeTiO3/Fe3O4 nanoparticles in membrane matrix. The results revealed that modified membranes in this study are comparable with that of other commercial ones.
