Intrinsic bipolar membrane characteristics dominate the effects of flow orientation and external pH-profile on the membrane voltage

The practical energy required for water dissociation reaction in bipolar membrane (BPM) is still substantially higher compared to the thermodynamic equivalent. This determined by voltage, consisting of (1) potential and (2) undesired voltage losses. Since pH gradient over BPM affects both components, this work, leveraged decrease BPM-voltage. We investigate effect four flow orientations: 1) co-flow, 2) counter-flow, 3) co-recirculation, 4) counter-recirculation, on BPM-voltage, using an analytical model chronopotentiometry experiments. predicts experimentally obtained accurately confirms importance orientation determining longitudinal profile bulk solution. However, contrast simulated results, our observations show orientations BPM-voltage be insignificant under operating conditions. When dominant, internal local inside determines its final shadowing external pH-gradient Therefore, although changing pH, it does not influence at junction layer hence Instead, opportunities reducing are realm improved catalysts ion exchange layers BPM.