Organic matter and dissolved salts removal in a microbial desalination cell with different orientation of ion exchange membranes

Abstract

AbstractTwo microbial desalination cells (MDCs), MDC-1 having anion exchange membrane (AEM) near anode and cation exchange membrane (CEM) near cathode and MDC-2 having CEM near anode and AEM near cathode were used for removal of total dissolved solids (TDS) and chemical oxygen demand (COD) from wastewater. Performance of MDCs was evaluated at different catholyte pH (8.0 and 3.0) using 0.2 g/L of KMnO4 as catholyte under dissolved salt concentrations of 8, 20, and 30 g/L in the middle chamber. Maximum Coulombic efficiency in MDC-1 (15%) and MDC-2 (11%) was observed at acidic catholyte pH. Highest TDS removal was obtained in MDC-1 (50%) having AEM near anode at higher salt concentration in middle chamber and acidic catholyte pH. Slightly lesser TDS removal was observed with alkaline catholyte pH. However, COD removal was more in MDC-2 (91%), where CEM was placed near anode.