Comparative study of microbial fuel cell performance using poly ether ether ketone-based anion and cation exchange membranes

Abstract

In this report, poly ether ether ketone (PEEK)-based anion and cation exchange membranes were assembled separately in two identical and compact microbial fuel cells (MFCs) without water and gas trapping between membrane and the electrode. We examined the use of these two membranes with the same electrode surface area as well as anode and cathode volumes. A maximum power density of 603 and 458 mW m−2 with a columbic efficiency of 76 and 61% were observed for quaternized poly ether ether ketone (QPEEK) and sulfonated poly ether ether ketone (SPEEK), respectively. A few solution chemistry parameters, which are leading factors behind the cell performance, such as variation in conductivity and solution pH in the two chambers were observed. In addition, the mobility of anions and cations (other than protons and hydroxyl ions in the case of cation and anion exchange membranes, respectively) under the inoculated conditions was also investigated. Further, the membrane charge-based biofilm growth was also analyzed by SEM and impedance spectroscopy to find its influence on the MFC performance.