Electricity generation from real industrial wastewater using a single-chamber air cathode microbial fuel cell with an activated carbon anode

Abstract

This study introduces activated carbon (AC) as an effective anode for microbial fuel cells (MFCs) using real industrial wastewater without treatment or addition of external microorganism mediators. Inexpensive activated carbon is introduced as a proper electrode alternative to carbon cloth and carbon paper materials, which are considered too expensive for the large-scale application of MFCs. AC has a porous interconnected structure with a high bio-available surface area. The large surface area, in addition to the high macro porosity, facilitates the high performance by reducing electron transfer resistance. Extensive characterization, including surface morphology, material chemistry, surface area, mechanical strength and biofilm adhesion, was conducted to confirm the effectiveness of the AC material as an anode in MFCs. The electrochemical performance of AC was also compared to other anodes, i.e., Teflon-treated carbon cloth (CCT), Teflon-treated carbon paper (CPT), untreated carbon cloth (CC) and untreated carbon paper (CP). Initial tests of a single air-cathode MFC display a current density of 1792 mAm, which is approximately four times greater than the maximum value of the other anode materials. COD analyses and Coulombic efficiency (CE) measurements for AC-MFC show the greatest removal of organic compounds and the highest CE efficiency (60 and 71%, respectively). Overall, this study shows a new economical technique for power generation from real industrial wastewater with no treatment and using inexpensive electrode materials.

Carbon‐Based Composites as Anodes for Microbial Fuel Cells: Recent Advances and Challenges

“…[21] Together with the reduced electron transfer resistance, active carbon-based MFC delivered a high power density up to 338 mW m À 2 . [22] To overcome the diffusion limitation and improve the biofilm surface area, carbon felt granules were suspended in the anode chamber by stirring. A high concentration of granules could provide more capacitance and active sites for biofilm attachment.…”

A Critical View of Microbial Fuel Cells: What Is the Next Stage?

“…Regarding the different types of waste suitable for MFCs, there is a huge variety of wastewaters that can be used as substrates for bacteria. This fact allows MFCs to be used to treat not only domestic wastewater but also industrial wastewater, such as from breweries, food‐processing plants, paper‐recycling plants, sanitary and swine streams, yeast extract, refineries, starch, marine sediments, organic acids, alcohols, sulfides, and algae . It is important to highlight that, in addition to the suitable types of wastewater, good performance of COD removal has been obtained.…”

“…It can be observed that nowadays, about 60 % of the studies related to MFCs use synthetic substrates, mainly glucose and acetate. Synthetic wastewater is frequently employed in MFCs, but its operation with real municipal and industrial wastewaters has also been tested satisfactorily . About 40 % of the studies use natural substrates, the sources of which show great diversity: raw domestic wastewater (40 %), marine sediments (25 %), and sewage sludge (10 %).…”

Biodegradation of TOC by Nano‐Fe2O3 Modified SMFC and Its Potential Environmental Effects**

“…In SMFC system, the electron transfer rate at the biofilm/ anode interface is considered as the key factor determining power generation capacity and organic contaminants removal efficiency. [21,22] In most previous SMFCs studies, modification for anode with various materials (e. g., transition metals and nanomaterials) was widely applied to adjust the anode surface morphology to enhance the electron transfer process. [23] Among these materials, nano-Fe 2 O 3 particles have attracted much more attention due to its unique advantages such as considerable electrocatalysis, chemical stability and low cost.…”