The Use of Different Electrode Materials for Electricity Production in a Microbial Fuel Cell Using a Klebsiella oxytoca Microorganism Under Different Operating Conditions

Abstract

Microbial fuel cells (MFCs) have been developed impressively over recent years. In order to take this technology from research to application, the performance of these systems needs to be further investigated and optimized. The electrode materials and operating conditions play a vital role in MFCs performance. In the current work, dual chamber MFC was used to investigate the performance of different electrode materials under stationary and flow conditions. Microorganism solution of Klebsiella oxytoca and Citrobacter Freundii inoculum was used in the anode chamber. Three electrode materials were investigated, namely activated carbon, graphite, and titanium. High current density and power output were obtained by activated carbon electrode and graphite, while titanium showed poor performance for bio-electricity production. The low flow velocity (or Reynolds number) in catholyte was found to enhance the energy production, while the high velocity caused a reduction in the produced current. The aeration of the cathode chamber had a negative effect on the produced current due to the transfer of dissolved oxygen to the microorganism chamber. Activated carbon showed high performance due to its high surface area with the achieved maximum power density of 462.74 mW/m² at Reynolds number of 7030.

Key findings

• ▸Activated carbon and graphite electrodes outperform titanium in bio-electricity production.
• ▸Low flow velocity in catholyte enhances energy production.
• ▸Aeration of cathode chamber reduces current production due to oxygen transfer.

Keywords

Identifiers

DOI

10.2174/2405520413999201019155324

Journal

Recent Innovations in Chemical Engineering (Formerly Recent Patents on Chemical Engineering)

Year

2021