Simultaneous organics removal and bio-electrochemical denitrification in microbial fuel cells

Abstract
Simultaneous organics removal and bio-electrochemical denitrification using a microbial fuel cell (MFC) reactor were investigated in this study. The electrons produced as a result of the microbial oxidation of glucose in the anodic chamber were transferred to the anode, which then flowed to the cathode in the cathodic chamber through a wire, where microorganisms used the transferred electrons to reduce the nitrate. The highest power output obtained on the MFCs was 1.7 mW/m2 at a current density of 15 mA/m2. The maximum volumetric nitrate removal rate was 0.084 mg NO3−–N cm−2 (electrode surface area) day−1. The coulombic efficiency was about 7%, which demonstrated that a substantial fraction of substrate was lost without current generation.