Biocathode application in microbial fuel cells: Organic matter removal and denitrification

The aim of this study is to investigate bioelectricity generation using a dual chambered biocathode microbial fuel cell (MFC). In this study, the effect of cathode influent nitrate concentration was investigated on power generation and wastewater treatment performance. Acetate was used as readily biodegradable carbon and electron donor source for microorganisms into anodic chamber, corresponding to 1000 mg/L influent COD. The biocathode MFC performance was evaluated for around 75 days following 360 days microorganism adaptation period. COD removal efficiency was 75% and slightly affected from the varying influent nitrate concentrations. However, autotrophic denitrification efficiency was adversely affected by increasing influent nitrate concentration and the maximum nitrate removal efficiency of around 70% was observed at the influent nitrate concentration of 50 mgNO^-₃/L. Additionally, the increasing nitrate concentration from 25 to 50 mg/L resulted in increasing the power density which approached to around 4 W/m².