Ceramic membrane modified with rice husk ash for application in microbial fuel cells

Abstract

Ceramic membranes have been widely used as an affordable cation exchange membrane in microbial fuel cells (MFCs). This study deals with the fabrication of low-cost ceramic membranes by blending rice husk ash (RHA) with soil for its application in MFCs. Ceramic membrane having 10% RHA exhibited higher proton mass transfer and lower oxygen diffusion. The presence of silica in RHA enhanced the hydration properties of the membrane and aided proton mobility form anode to cathode chamber. Performance of the MFCs using modified (with RHA, MFCT) and unmodified (without RHA, MFCC) membrane was evaluated for the treatment of rice mill wastewater under continuous mode operation. The maximum volumetric power densities were 2.14 W m?3 and 1.33 W m?3, and COD removal efficiencies were 70.7 � 1.24% and 63.8 � 1.08% for MFCT and MFCC, respectively. Form the electrochemical impedance spectroscopy (EIS) study, ohmic resistance (R?) of MFCC and MFCT was found to be 91.3 ? and 47.1 ?, respectively. The RHA composite membrane displayed less tendency of membrane fouling, making it more favorable for long-term operation. This study reveals that the RHA composite membrane could serve as a suitable alternative to expensive polymeric membranes in MFC with higher power performance and minimum oxygen diffusion. � 2020