A Perspective Review on Microbial Fuel Cells in Treatment and Product Recovery from Wastewater

Abstract

The treatment of wastewater is an expensive and energy-extensive practice that not only ensures the power generation requirements to sustain the current energy demands of an increasing human population but also aids in the subsequent removal of enormous quantities of wastewater that need to be treated within the environment. Thus, renewable energy source-based wastewater treatment is one of the recently developing techniques to overcome power generation and environmental contamination issues. In wastewater treatment, microbial fuel cell (MFC) technology has demonstrated a promising potential to evolve as a sustainable approach, with the simultaneous recovery of energy and nutrients to produce bioelectricity that harnesses the ability of electrogenic microbes to oxidize organic contaminants present in wastewater. Since traditional wastewater treatment has various limitations, sustainable implementations of MFCs might be a feasible option in wastewater treatment, green electricity production, biohydrogen synthesis, carbon sequestration, and environmentally sustainable sewage treatment. In MFCs, the electrochemical treatment mechanism is based on anodic oxidation and cathodic reduction reactions, which have been considerably improved by the last few decades of study. However, electricity production by MFCs remains a substantial problem for practical implementations owing to the difficulty in balancing yield with overall system upscaling. This review discusses the developments in MFC technologies, including improvements to their structural architecture, integration with different novel biocatalysts and biocathode, anode, and cathode materials, various microbial community interactions and substrates to be used, and the removal of contaminants. Furthermore, it focuses on providing critical insights and analyzing various types, processes, applications, challenges, and futuristic aspects of wastewater treatment-related MFCs and thus sustainable resource recovery. With appropriate planning and further studies, we look forward to the industrialization of MFCs in the near future, with the idea that this will lead to greener fuels and a cleaner environment for all of mankind.

Identification of bacteria involved in non-sulfate based hydrogen sulfide production in an aquaculture environment

“…Acetate is not produced directly from cysteine degradation but can be derived from pyruvate produced by cysteine degradation if the bacteria carry the acetate synthesis pathway (58). Conversely, acetate concentration decreased in the incubations with sulfate, attributed to the consumption of acetate by SRM in dissimilatory sulfate reduction (59). We also observed differences in H 2 S production profiles between the two enrichment conditions, as cysteine led to almost immediate H 2 S production, while the process started slower in sulfate-enriched reactors.…”

Microbial Fuel Cell Construction Features and Application for Sustainable Wastewater Treatment

“…MFCs can use a variety of biodegradable organic molecules from landfill leachates, industrial waste, food waste, municipal wastewater, dairy waste, and other sources [ 87 ]. Additionally, MFCs can treat wastewater with a wide COD range, reducing both energy use and greenhouse gas emissions [ 88 ]. It has been determined that converting waste directly into high-value energy, clean electricity, or chemical goods is a superior solution for solving the excess sludge and energy problems in traditional wastewater treatment systems [ 89 , 90 ].…”

Electroactive Bacteria in Natural Ecosystems and Their Applications in Microbial Fuel Cells for Bioremediation: A Review

“…There are few works that report study cases of microbial fuel cells at full scale, which treat a high amount of wastewater. MFC scale-up and commercialization poses problems such as high construction costs, difficulty in developing high power structures, the MFC lifetime, and maintenance of a high level of efficiency, with difficulties in balancing yields with overall system upscaling [ 96 , 97 ]. A full scale MFC system was tested by Liang et al [ 98 ] and operated for 1 year.…”