The performance of aerated and ferricyanide catholytes on the bioelectricity production was evaluated in dual chambered microbial fuel cell (MFC) (mediatroless anode; graphite electrodes) employing selectively enriched H-2 producing mixed consortia as anodic inoculum. Two MFCs with aerated catholyte (MFCAC) and ferricyanide catholyte (MFCFC) were operated separately to elucidate the difference in power generation potential and carbon removal efficiency under similar operating conditions [ambient pressure; room temperature (28 +/- 2 degrees C); acidophilic microenvironment (pH 6)]. The experimental data demonstrated the feasibility of in situ bioelectricity generation along with wastewater treatment. Effective power generation and substrate removal efficiency was documented in the fuel cell operated with ferricyanide catholyte (586 mV; 2.37 mA; 0.559 kg COD/m(3) day) than aerated catholyte (572 mV; 1.68 mA; 0.464 kg COD/m(3) day). Maximum power yield (0.635 W/kg CODR and 0.440 W/kg CODR) and current density (222.59 mA/m(2) and 190.28 mA/m(2)) was observed at 100 Omega resistor with ferricyanide and aerated catholytes, respectively. The study documented both wastewater treatment and electricity production through direct conversion of H-2 in a single system. (c) 2007 Elsevier Ltd. All rights reserved.