A Critical Review on Microbial Fuel Cells Technology: Perspectives on Wastewater Treatment

Abstract

Increasing demand for renewable energy in the backdrop of global change calls for waste valorization and circular economy strategies. Public health concerns and demand for clean energy provide impetus to the development of wastewater based MFC. Wastewater treatment and simultaneous generation of bioelectricity offer a myriad of environmental benefits. Nevertheless, it is pertinent to know the challenges with the microbial fuel cell (MFC) technology to upscale the wastewater based MFC. This paper attempts to critically analyse the processes, application, challenges and opportunities of wastewater based MFCs. A literature survey was conducted to find out the advances in the field of wastewater based MFCs and the focus was to decipher the challenges to the implementation of wastewater based MFCs. Recent developments in MFC technology have improved the power output and studies show that a diverse group of organic-rich wastewater can be treated with MFCs. The developments include improvements in MFC configuration, development of biocatalysts and biocathode, anodic biofilm formation, microbial community interactions, and progress in the organic and pollutant removal. Nevertheless, the MFC technology is replete with challenges about the organic removal rate, power density, electrode performance limiting factors, economic viability, high initial and maintenance cost and difficulty to maintain the exoelectrogens activity in a complex wastewater environment. Opportunities exist in scaling up of MFCs, integration with other wastewater treatment methods and measures to minimise the operating costs. MFCs have the potential to increase the resilience capacity of the sustainable wastewater treatment plant.

Treatment of Organic and Sulfate/Sulfide Contaminated Wastewater and Bioelectricity Generation by Sulfate-Reducing Bioreactor Coupling with Sulfide-Oxidizing Fuel Cell

“…To minimize environmental pollution, the SOFC was operated without the addition of synthetic electron transport mediators during the operation. The produced sulfide from the sulfate-reducing process in SRBR, a biological compound, was used as an electron mediator, which transfers electrons to the anode electrode [35,36]. Sulfide can be removed in the SOFC when it is oxidized through electrochemical reactions at the anode.…”

“…The resulting electrons are delivered to the anode and transported to the cathode through an external circuit, producing electricity. Then, the released protons in the anodic chamber migrate through a proton exchange membrane (PEM) into the cathode chamber [36,37].…”

Energy Production in Microbial Fuel Cells (MFCs) during the Biological Treatment of Wastewater from Soilless Plant Cultivation

“…Many projects have attempted to modify MFC and search for new configurations that would enable more effective treatment of different types of wastewater. For instance, Park et al [56,57] used a flat-panel air-cathode for domestic sewage treatment, which after eight months of operation was able to remove 85% of the COD and 94% of TN. In turn, Zhang Y. et al [58] proposed harnessing algae in a microbial fuel cell, because during growth resulting from photosynthesis, algae exhibit the ability to assimilate organic components.…”

Microbial Fuel Cell Construction Features and Application for Sustainable Wastewater Treatment

“…For the formation of biocathodes, stainless steel is often utilized. Carbon-based materials such as graphite felt, activated carbon, granular graphite, etc., are also used for biocathode formation [ 52 , 53 , 54 , 55 ]. The efficiency of biocathodes can be increased by providing an enlarged surface area for biofilm formation.…”