Electrochemical Parameters of Heterogeneous Bipolar Membranes: Dependence on the Structure and Nature of Monopolar Layers

The current–voltage curves, transport numbers of ions, and electrochemical impedance spectra are obtained for pilot samples of heterogeneous bipolar membranes synthesized from cation- and anion-exchange membranes. In the synthesis, the composition of the monopolar layers of membranes was varied or a catalyst was introduced into them. The voltage drop and the frequency spectra at the pilot membranes are close to those for industrial membrane MB-3. The transport numbers of co-ions in the pilot membranes are smaller and those of the hydrogen and hydroxyl ions are larger than in MB-3. The effective water dissociation constants in the pilot membranes, calculated from the impedance spectra, are close to those of MB-3.