Behavior of two-chamber microbial electrochemical systems started-up with different ion-exchange membrane separators

•The use of certain anion/cation exchange membranes in MFC is first presented.•The type of membrane separator affected the efficiency of MFC start-up.•MFC with anion exchange membrane showed outstanding performance.•Geobacter was dominantly selected on anodes independently of membrane type.•Voltammograms indicated various anode surface coverage of redox components. In this study, microbial fuel cells (MFCs) – operated with novel cation- and anion-exchange membranes, in particular AN-VPA 60 (CEM) and PSEBS DABCO (AEM) – were assessed comparatively with Nafion proton exchange membrane (PEM). The process characterization involved versatile electrochemical (polarization, electrochemical impedance spectroscopy – EIS, cyclic voltammetry – CV) and biological (microbial structure analysis) methods in order to reveal the influence of membrane-type during start-up. In fact, the use of AEM led to 2–5 times higher energy yields than CEM and PEM and the lowest MFC internal resistance (148 ± 17 Ω) by the end of start-up. Regardless of the membrane-type, Geobacter was dominantly enriched on all anodes. Besides, CV and EIS measurements implied higher anode surface coverage of redox compounds for MFCs and lower membrane resistance with AEM, respectively. As a result, AEM based on PSEBS DABCO could be found as a promising material to substitute Nafion.