In this study, separation performance for monovalent salts (NaCl, KCI) and divalent salts (CaCl 2 MgCl 2 ) was investigated by electrodialysis at pH 6.0–6.5, 4.0 and 2.0 using constant voltage mode of operation. TS-1–10 electrodialysis equipment (Tokuyama) modified with rotameters was employed in experimental studies. The effect of electrical potential, pH and ion valency on separation performance was studied at room temperature using a constant flow rate. The efficiencies of each run were evaluated as specific power consumption with the electrical energy consumed only in stack.