Structure and working principle:

Under the action of a DC electric field, the dielectric ions in the water passing through the separator move in a directional manner because the exchange membrane is selective for ions. Between a pair of electrodes of the electrodialyzer, groups of negative membranes, cation membranes and partitions (A, B) are alternately arranged to form a concentrated chamber and a dilute chamber (that is, cations can pass through the cation membrane, and anions can pass through the anion membrane. ). The cations in the water in the fresh chamber migrate toward the negative electrode, pass through the cation membrane, and are intercepted by the anion membrane in the concentrated chamber; the anions in the water move toward the negative electrode.