Nguyen Thi My Linh, Pham The Hai

Vietnam Journal of Biotechnology • 2022

Nowadays, instant assessment of the organic content in wastewater is an urgent requirement to reduce water pollution. Microbial fuel cells (MFCs) can be used as effective biosensors for rapidly measuring BOD concentration of wastewater. However, wastewaters from different sources may consist of diverse chemical components, which may affect the BOD-measuring performance of MFC-type biosensors. Therefore, in this research, we tested different input substrates for the BOD sensor type MFC (MFC_BOD) to investigate their effects on the performance of the MFC. The substrates belonging to diverse groups such as carbohydrates, organic acids, amino acids and some chlorinated compounds (xenobiotics) were tested at different concentrations equivalent to BOD levels from 10 to 200 mg L-1. Concurrently, we also analyzed the alteration of the bacterial community in the anode of the MFC when tested with those different substrates by using PCR-DGGE. Our results showed that the MFC_BOD could have linear current-to-BOD responses (with the respective R2 values >0.9) to more metabolizable substrates such as carbohydrates, organic acid and glycerol; while it responded less sensitively at different degrees to some amino acids (serine, threonine and methionine) and did not respond to chloroform and chlorobenzene (chlorinated compounds). PCA and bacterial community analysis results surprisingly imply that such different responses may be solely due to different bio(electro)chemical processes associated with the substrates but not due to changes in the composition of the bacterial community. The results suggest that, to enable the MFC_BOD to accurately sense the BODs of the wastewaters containing recalcitrant or toxic substrates, special procedures are required to enrich in the anode the bacterial communities acclimated to the substrates right from the beginning

Nabea M. Mahdi, Ahmed H. Ali

Journal of Engineering and Sustainable Development • 2022

In this work, Single chamber Microbial fuel cells (SCMFCs) are a versatile technology is depending on the interaction mechanisms of bacteria, to produce bioelectricity simultaneously and treat Congo red (CR) dye from aqueous solution at different pH (6.5-8). Electricity generation from the biodegradable organic substrate (sucrose) accompanied by decolorization of azo dye was investigated in the batch test results showed that more than 99% decolorization demonstrated at UV-Visible Spectrophotometer (500 nm) was achieved within 20 days and maximum output voltage (889 mv) had been obtained in an open circuit at a pH value of 7.5. Microbial community analysis showed that species in live sludge and the impact of bacteria grown on removal and voltage.

Jin-Tao Li, Shao-Hui Zhang, Yu-Mei Hua

Water Science and Technology • 2013

The effects of pH, chemical oxygen demand (COD) concentration and external resistance on denitrifying microbial fuel cell were evaluated in terms of electricity generation characteristics and pollutant removal performance. The results showed that anodic influent with weakly alkaline or neutral pH and cathodic influent with weakly acidic pH favored pollutant removal and electricity generation. The suitable influent pH of the anode and cathode were found to be 7.5–8.0 and 6.0–6.5, respectively. In the presence of sufficient nitrate in the cathode, higher influent COD concentration led to more electricity generation and greater pollutant removal rates. With an anodic influent pH of 8.0 and a cathodic influent pH of 6.0, an influent COD concentration of 400 mg/L was deemed to be appropriate. Low external resistance favored nitrate and COD removal. The results suggest that operation of denitrifying microbial fuel cell at a lower external resistance would be desirable for pollutant removal but not electricity generation.

Justin P. Jahnke, Deborah A. Sarkes, Jessica L. Liba et al.

Energies • 2021

Microorganism affinity for surfaces can be controlled by introducing material binding motifs into proteins such as fimbrial tip and outer membrane proteins. Here, controlled surface affinity is used to manipulate and enhance electrical power production in a typical bioelectrochemical system, a microbial fuel cell (MFC). Specifically, gold-binding motifs of various affinity were introduced into two scaffolds in Escherichia coli: eCPX, a modified version of outer membrane protein X (OmpX), and FimH, the tip protein of the fimbriae. The behavior of these strains on gold electrodes was examined in small-scale (240 µL) MFCs and 40 mL U-tube MFCs. A clear correlation between the affinity of a strain for a gold surface and the peak voltage produced during MFC operation is shown in the small-scale MFCs; strains displaying peptides with high affinity for gold generate potentials greater than 80 mV while strains displaying peptides with minimal affinity to gold produce potentials around 30 mV. In the larger MFCs, E. coli strains with high affinity to gold exhibit power densities up to 0.27 mW/m2, approximately a 10-fold increase over unengineered strains lacking displayed peptides. Moreover, in the case of the modified FimH strains, this increased power production is sustained for five days.

Masoud Karamzadeh, Milad Kadivarian, Peyman Mahmoodi et al.

Scientific Reports • 2023

Abstract Microbial fuel cells (MFCs) serve two main purposes: clean energy production and wastewater treatment. This study examines the impact of different carbon sources on MFC performance and develops a mathematical model to replicate the polarization curve. The biological reactor employed three types of carbon sources: glucose as a simple feed, microcrystalline cellulose (MCC), and a slurry of the organic component of municipal solid waste (SOMSW) as complex feeds. The MFCs were operated in both open and closed circuit modes. The maximum open circuit voltages achieved were 695 mV for glucose, 550 mV for MCC, and 520 mV for SOMSW as substrates. The influence of the substrate in closed circuit mode was also investigated, resulting in maximum power densities of 172 mW/m 2 , 55.5 mW/m 2 , and 47.9 mW/m 2 for glucose, MCC, and SOMSW as substrates, respectively. In the second section, a mathematical model was developed to depict the polarization curve while considering voltage losses, namely activation, ohmic, and concentration loss, with an average relative error (ARE) of less than 10%. The mathematical models demonstrated that the activation loss of voltage increased with the complexity of the substrate and reached its peak value when SOMSW was used as the substrate.

D Permana, Djaenudin

IOP Conference Series: Earth and Environmental Science • 2019

Abstract The wastewater of tofu industries consists of organic compounds and in turn, may affect the environment; therefore, a proper wastewater treatment system is needed. Based on its characteristics, biological treatment is a good method to treat tofu wastewater. One of the biological treatment methods that can be used is Microbial Fuel Cell (MFC), which can reduce the pollutant and at the same time generating low-power electricity. This system utilizes microorganisms as a biocatalyst to degrade organic compounds in the wastewater. This study aimed to examine the performance of Single Chamber MFC (SCMFC) to decrease biochemical oxygen demand (BOD 5 ) and chemical oxygen demand (COD) of the tofu wastewater, as well as to generate electricity. Tofu wastewater was sterilized then filled into the reactor. Microbes that either have been acclimatized or not acclimatized were then added. Bacteria that were used were one of the three consortiums of native microbes of tofu wastewater, namely Escherichia coli, Saccharomycopsis fibuligera, and mixed culture of E. coli and S. fibuligera. Carbon (C) was used as both anode and cathode. We found that the acclimatized mixed culture of E. coli and S. fibuligera showed high BOD 5 , COD removal after 48 hours at 76.57 and 77.22 %, respectively. It also generated 5.49 mA of current, 757 mV of voltage, and the electrical energy produced was 9.216 x10 − 5 kWh. The results suggest that using mixed microorganisms is one of the strategies to improve the electricity generation of MFC. The scale-up of the volume, selection of microorganism cultures, and immobilization could be other strategies for further studies.

Mehran Abbaszadeh Amirdehi, Lingling Gong, Nastaran Khodaparastasgarabad et al.

ChemRxiv • 2021

Power overshoot can hinder determination of maximum power densities in microbial fuel cells (MFCs). In this work, a microfluidic approach was used to study overshoot in an MFC containing a pure culture of electroactive biofilms (EAB) containing Geobacter sulfurreducens. After 1-month operation under constant flow of an ideal nutrient medium, the MFC health began to degrade, marked by voltage loss and the appearance of anomalies in the power density curves. One such anomaly was a chronic power overshoot, accompanying a loss of both measured power and current density on the high-current side of the power density curve. The degree of power overshoot was quantified while certain flow-based interventions were applied, notably the shear erosion of the EAB outer layer. Next, two approaches to acclimation were demonstrated to treat the remaining overshoot. The standard approach, which acclimates the MFC to high currents before a standard polarization test, eliminated the remaining overshoot and returned maximum power densities to initial levels, but maximum current density remained lower than the initial level. A microfluidic-assisted “long-hold polarization test” enabled efficient in situ acclimation of each external resistor during the measurement. Despite the health-compromised MFC, this method provided long-term stability during the polarization test, resulting in power and current density measurements that exceeded those made on the healthy MFC using the standard polarization test. We conclude that slower electron transfer kinetics in unhealthy MFCs can provoke overshoot by prolonging the time to reach steady state during the polarization test, but a properly designed measurement overcomes this problem.

Jia Mei Song, Dong Ping Sun, Lei Zhao et al.

Advanced Materials Research • 2011

Microbial Fuel Cells (MFCs) are systems that can convert chemical energy into electrical energy by biological oxidation, current effort to improve the power output is limited by the lack of knowledge about the electrochemical activity bacteria and researches on the power generation mechanisms of pure strains are rare. In this study, the exoelectrogenic (”exo” for exocellular) bacterium staphylococcus SJ-1 was directly isolated from the MFC, which was stably run for 90 days. Cyclic Voltammetry (CV) indicated that temporary mediator produced by SJ-1 may take the work of transferring electron. A new built double-chamber MFC was inoculated with pure SJ-1, and after 40 days enrichment, the system produced 520mW/m 2 power density and the highest open circuit voltage (OCV) reached to 616mV, the power output was higher than most of the single-strain MFCs reported.

Yao-Yu Lin, Hsin-Tien Li, Han-Yi Chen et al.

ECS Meeting Abstracts • 2022

Developing environment-friendly and sustainable energy is urgent these days, as it can solve energy shortages and the pollution that come from fossil fuel. Therefore, Plant microbial fuel cells (PMFCs) start to get attention recently. PMFC is a novel technology that can convert chemical energy into electricity by using microbial in the rhizosphere of plants without producing harmful byproducts during the process. However, PMFCs suffer from some practical issues such as low power output and high costs of electrode materials. This gives rise to the progress of electrode material which can improve the power output and reduce the cost. To break through the limits of PMFCs, the agricultural waste-derived carbons were prepared and optimized as the anode material in our self-designed Canna-indica PMFCs in this study. Green carbon materials utilizing agricultural waste as precursors are not only environment-friendly but also a part of circular economy which helps to mitigate bio-waste and improve society sustainability. The biowaste-derived activated carbon materials were characterized by Brunauer-Emmett-Teller (BET) surface area analyzer, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The high surface area, porosity morphology, and good conductivity of the biowaste-derived activated carbon are the promising characteristics of high-performance anode materials of PMFCs. The maximum power density of our self-made PMFC device can reach 61 mW m −2 . The average power density was maintained at 23 mW m −2 during the long-term measurement. All of the results in this study demonstrate the potential of using agricultural waste as electrode material for improving the electricity production of PMFCs.

Roshan Bellary, Emily Lan, Richard Hockett et al.

Journal of Emerging Investigators • 2023

Future long-term space travel requires both efficient waste management and renewable energy production to be feasible. One such option in addressing these issues is a microbial fuel cell (MFC) that converts chemical energy in organic matter to electrical energy through biological processes of microbes. Electroactive biofilms are special colonies of microbes that utilize an extracellular matrix to increase the endurance and growth of bacterial colonies through the sharing of resources and the depositing of electrons. We studied the power production of a biofilm MFC by testing the fuel cell in microgravity over time on the International Space Station (ISS). We utilized Shewanella oneidensis, an established electroactive biofilm, to break down a nutrient solution and release electrons and protons, producing a voltage difference across the cell. The S. onedensis biofilm grew more prolifically under low-pressure conditions, making it well suited for microgravity; consequently, the consumption of sodium lactate in a larger biofilm caused an increase in anaerobic respiration of the bacteria. This increased the voltage difference recorded across the cell and the corresponding power of the MFC. Our results are consistent with our hypothesis that there would be an increase in voltage and power production over time; however, an insufficient amount of growth medium eventually led to a decrease in voltage and power production as the biofilm died out. Power output during microgravity testing increased over time, coinciding with nutrient solution pump cycles. This experiment established that an MFC is a promising avenue for the development of renewable energy in microgravity.

P. P. Rajesh, Md. T. Noori, M. M. Ghangrekar

Water Science and Technology • 2018

Abstract Methanogenic substrate loss is reported to be a major bottleneck in microbial fuel cell (MFC), which significantly reduces the power production capacity and coulombic efficiency (CE) of this system. Nitroethane is found to be a potent inhibitor of hydrogenotrophic methanogens in rumen fermentation process. Influence of nitroethane pre-treated sewage sludge inoculum on suppressing the methanogenic activity and enhancing the electrogenesis in MFC was evaluated. MFC inoculated with nitroethane pre-treated anodic inoculum demonstrated a maximum operating voltage of 541 mV, with CE and maximum volumetric power density of 39.85% and 20.5 W/m3, respectively. Linear sweep voltammetry indicated a higher electron discharge on the anode surface due to enhancement of electrogenic activity while suppressing methanogenic activity. A 63% reduction in specific methanogenic activity was observed in anaerobic sludge pre-treated with nitroethane, emphasizing the significance of this pre-treatment for suppressing methanogenesis and its utility for enhancing electricity generation in MFC.

Yuichiro Tabuchi, Takeshi Shiomi, Osamu Aoki et al.

ASME 2010 8th International Fuel Cell Science, Engineering and Technology Conference: Volume 1 • 2009

Heat and water transport in polymer electrolyte membrane fuel cell (PEMFC) has considerable impacts on cell performance under high current density which is desired in PEMFC for automobiles. In this study, the impact of rib/channel, heat and water transport on cell performance under high current density was investigated by experimental evaluation of liquid water distribution and numerical validation. Liquid water distribution between rib and channel is evaluated by Neutron Radiography. In order to neglect the effect of liquid water in channel and the distribution of oxygen and hydrogen concentration distribution along with channel length, the differential cell was used in this study. Experimental results show that liquid water under channel was dramatically changed with Rib/Channel width. From numerical study, it is found that the change of liquid water distribution was strongly affected by temperature distribution between rib and channel. In addition, not only heat transport but also water transport through membrane also significantly affected cell performance under high current density operation. From numerical validation, it is concluded that this effect on cell performance under high current density could be due to the enhancement of back-diffusion of water through membrane.

Jie Yang, Sasan Ghobadian, Reza Montazami et al.

ASME 2013 11th International Conference on Fuel Cell Science, Engineering and Technology • 2013

Microbial fuel cell (MFC) technology is a promising area in the field of renewable energy because of their capability to use the energy contained in wastewater, which has been previously an untapped source of power. Microscale MFCs are desirable for their small footprints, relatively high power density, fast start-up, and environmentally-friendly process. Microbial fuel cells employ microorganisms as the biocatalysts instead of metal catalysts, which are widely applied in conventional fuel cells. MFCs are capable of generating electricity as long as nutrition is provided. Miniature MFCs have faster power generation recovery than macroscale MFCs. Additionally, since power generation density is affected by the surface-to-volume ratio, miniature MFCs can facilitate higher power density. We have designed and fabricated a microscale microbial fuel cell with a volume of 4 μL in a polydimethylsiloxane (PDMS) chamber. The anode and cathode chambers were separated by a proton exchange membrane. Carbon cloth was used for both the anode and the cathode. Shewanella Oneidensis MR-1 was chosen to be the electrogenic bacteria and was inoculated into the anode chamber. We employed Ferricyanide as the catholyte and introduced it into the cathode chamber with a constant flow rate of approximately 50 μL/hr. We used trypticase soy broth as the bacterial nutrition and added it into the anode chamber approximately every 15 hours once current dropped to base current. Using our miniature MFC, we were able to generate a maximum current of 4.62 μA.

Wanjing Wu, Duwei Zhang, Ping Fang

IOP Conference Series: Earth and Environmental Science • 2020

Abstract As a bioelectrochemical hybrid system, microbial fuel cell converts chemical energy into electrical energy through microbial metabolism, which has great advantages of energy conservation and environmental protection, high energy conversion efficiency, and reduced sludge volume. Therefore, how to improve the power generation performance and output power of MFC has been a hot topic in recent years. Based on this, on the basis of reviewing many literatures, this review analyzes the main factors influencing the electrical performance of MFC by combining the principle of MFC and its electronic transfer mechanism, including battery reactor structure, exchange membrane, anode microorganisms, electrode materials and parameters, etc. At the same time, the application prospect of MFC is discussed, including CW-MFC coupling technology, biosensor and sewage treatment technology. Finally, the present challenges of MFC are put forward, and a better application research direction is proposed for the future of MFC.

Abhijeet P. Borole, Choo Y. Hamilton, Douglas S. Aaron et al.

Biotechnology Progress • 2009

Abstract A compact, three‐in‐one, flow‐through, porous, electrode design with minimal electrode spacing and minimal dead volume was implemented to develop a microbial fuel cell (MFC) with improved anode performance. A biofilm‐dominated anode consortium enriched under a multimode, continuous‐flow regime was used. The increase in the power density of the MFC was investigated by changing the cathode (type, as well as catholyte strength) to determine whether anode was limiting. The power density obtained with an air‐breathing cathode was 56 W/m 3 of net anode volume (590 mW/m 2 ) and 203 W/m 3 (2160 mW/m 2 ) with a 50‐mM ferricyanide‐based cathode. Increasing the ferricyanide concentration and ionic strength further increased the power density, reaching 304 W/m 3 (3220 mW/m 2 , with 200 mM ferricyanide and 200 mM buffer concentration). The increasing trend in the power density indicated that the anode was not limiting and that higher power densities could be obtained using cathodes capable of higher rates of oxidation. The internal solution resistance for the MFC was 5–6 Ω, which supported the improved performance of the anode design. A new parameter defined as the ratio of projected surface area to total anode volume is suggested as a design parameter to relate volumetric and area‐based power densities and to enable comparison of various MFC configurations. Published 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009

Sk Ismath Ara Jahan, Rajesh Kumar Chanda, Biplob Kumar Biswas

Chemical Engineering Research Bulletin • 2023

One of the recent talked-about issues is zero-carbon emission for ensuring sustainable development. Microbial fuel cell (MFC), a bioelectrochemical process, has attracted much attention due to its potential to be an alternative renewable energy source that can reduce carbon dioxide and methane emission as well. An additional benefit of MFC is that it is aptly capable of treating wastewater. Moreover, this technology is considered to be cheaper and poses no negative impact on environment. In this research a dual-chamber microbial fuel cell was constructed using low-cost and locally available materials. The designed dimension of each chamber was 30.5 cm × 20 cm × 20 cm where working volume was set as 5 L due to ease of handling. The MFC was operated using cow dung substrates, which were collected from the nearby village of Jashore University of Science and Technology campus. The wastewater used in this research was collected from the drain of the same campus (23.23424°N, 89.12609°E). Each set of experiment was conducted for two weeks (14 days) at a stretch. Considering bioelectricity production by the MFC, cow dung was found to be effective. Maximum power (0.8 mW) was produced in a single day during the experiment at a substrate concentration of 25 g/L. The cow dung along with the collected wastewater was investigated to find the effect of factors such as pH. Experiments were performed at varying pH (7, 8 and 10) at room temperature for 14 days. The maximum extent of current density (270 mA/m2), power density (167 mW/m2), and voltage (881 mV) were found at pH 8 by using drainage wastewater as a feedstock in combination with cow dung from the microbial fuel cell. The treatment of wastewater using the MFC demonstrated varied efficacy, achieving COD removal rates of 88.3% at pH 7, 90.2% at pH 8, and 84.4% at pH 10. The results highlight the MFC's potential as a dual-purpose technology for effective pollutant removal and bioelectricity generation, particularly at an optimal pH of 8. These findings underscore the MFC's potential for dual-use in pollutant removal and energy generation, contributing to energy security. Chemical Engineering Research Bulletin 23 (2023): 1-5

T. K. Sajana, M. M. Ghangrekar, A. Mitra

Water Science and Technology • 2013

The performance of three sediment microbial fuel cells (SMFCs) was evaluated at different feed water pH and electrode spacing for chemical oxygen demand (COD) removal, total nitrogen (TN) removal, and power density; while offering in situ remediation of aquaculture pond water. SMFC-A was operated at the feed water pH of 6.5 and spacing between the electrodes of 100 cm. SMFC-B and SMFC-C were operated at feed water pHs of 8.5 and 6.5, respectively, and distance between electrodes of 50 cm. The anode and cathode were connected with concealed copper wire through an external load of 100 Ω. The average amount of total COD removal rate and TN removal rate, per unit area of cathode, were 1.72 ± 0.06 and 0.021 ± 0.007 g/m2 d in SMFC-A, 1.03 ± 0.08 and 0.024 ± 0.005 g/m2 d in SMFC-B, and 1.14 ± 0.01 and 0.017 ± 0.001 g/m2 d in SMFC-C, respectively. SMFC-A, operated with higher distance between electrodes, demonstrated better removal of organic matter and highest open circuit voltage of 0.903 V. SMFCs with less feed pH (6.5) gave higher COD removal and feed pH of 8.5 gave higher TN removal. SMFCs operated with lesser distance between electrodes gave higher power density.

P. P. Rajesh, P. Christine, M. M. Ghangrekar

Water Science and Technology • 2021

Abstract The marine algae Chaetoceros contains hexadecatrienoic acid, which suppresses methanogen development and improves the coulombic efficiency (CE) of microbial fuel cells (MFC). To inhibit the methanogens, optimum concentration of marine algae should be added to the anaerobic sludge to enhance the performance of MFC. A varying concentration of Chaetoceros ranging from 1 to 20 mg/mL was carried out for pretreatment of an anaerobic-mix consortium to suppress methanogens. MFC inoculated with pretreated anaerobic sludge with 10 mg/mL Chaetoceros showed a maximum power density of 21.62 W/m3 and a maximum CE of 37.25%, which was considerably higher than the treatment with other concentrations. At 10 mg/mL concentration, Tafel analysis of the anode in the MFC showed a higher exchange current density of 66.35 mA/m2 and a lower charge transfer resistance of 0.97 Ω.m2, revealing higher bio-electrochemical activity. The performance of MFC improved when the concentration of Chaetoceros was increased up to 10 mg/mL, but then began to decline as the concentration increased further. Thus, the optimum dose of Chaetoceros to be added in the mix-anaerobic consortium to optimize the power performance of MFC was determined, which can be carried out in scaled-up MFCs.

Divya Vempati, Arun Kumar

Water Science & Technology • 2024

ABSTRACT Industrial wastewaters from the cosmetic industry contain high organic strength and a mixture of nanoparticles (NPs). Sediment microbial fuel cell (MFC) is an emerging nature-based technology that can treat complex wastewaters. The aim of this study is to understand the effect of a binary mixture of zinc oxide (ZnO) and copper oxide (CuO) NPs (concentration: 1 + 1 and 10 + 10 mg/L) on the organic matter removal, power generation, and biofilm health of sediment MFCs after a long-term operation of 120 days. The high chemical oxygen demand (COD) removal (>95%) observed for all reactors signified the minimal impact of 10 mg/L NP mixture on treatment. The dissolved organic carbon (DOC) removal from the sediment was reduced by 8% due to NPs. NPs also led to 42.2% higher anode extracellular polymeric substances (EPS) and 46.65% lesser cathode EPS generation. The maximum power density of 0.29 mW/m2 was obtained for the 10 mg/L NP reactor, with the average being 23% higher than the no-NP control reactor. This was the first study to explore the effect of the mixture of NPs on the performance of an MFC. The results indicated that sediment MFCs can sustain high mixture concentrations of NPs. Furthermore, variation of parameters can aid in establishing the feasibility of this technology for treating wastewater with NPs.

Nurettin Çek, Ahmet Erensoy, Namık Ak et al.

International Journal of Chemical Reactor Engineering • 2021

Abstract Moving towards green technology, alternatives to current detrimental, unsustainable, and expensive energy applications for eco-friendly energy are attracting great attention. Resource recycling and the convenient treatment of animal waste to diminish its nature impact are recently momentous subjects. Microbial fuel cells used cow waste have remarkable potential in electrical energy generation for clean, renewable and sustainable operation. In this study, double-chambered MFC was manufactured using cow manure as raw material at the anode chamber, graphite as the anode and cathode electrodes, fountain water in the cathode chamber, and proton exchange membrane. Because bacteria a catalytic reaction for the latent chemical energy of the cow manure was effectuated as a result of this, MFCs produced electricity. Electricity production performance of this MFC at low temperature (0–10 °C) conditions was examined. This MFC produced a maximum of 204.9 ± 0.1 mV open circuit voltage and 57.387 mW/m 2 power density under low temperature conditions. In particular, the sustainability and applicability of MFCs have been increased thanks to this operation done at low temperatures (0–10 °C).

Jason J. Keleher, Thomas J. Beckmann, Joseph Edward Lambert et al.

ECS Meeting Abstracts • 2018

Microbial fuel cells (MFCs) have gained a significant amount of interest in the pursuit of alternative energy sources. Current research has investigated the optimization of maximum power production via the development of novel carbon-based electrodes to reduce cost and increase efficiency. This research focused on the development of a biomimetic cellulose-based electrode containing a nanocomposite conductive polymer matrix which has shown to improve biofilm stability and electron transfer. More specifically the incorporation of β-cyclodextrin (β-CD) enhances microbial adsorption and biofilm formation via increased docking efficiency. Furthermore, the addition of a conducting polymer has enhanced electron transfer throughout the composite medium. Atomic force microscopy (AFM) and open circuit potential (OCP) measurements were correlated to microbial fuel cell performance to further validate the role of biofilm formation and the electron transfer process. Additionally, the mechanisms of individual cellular adhesion and its role in electron transfer were probed using epifluorescent optical tweezers coupled with OCP measurement.

Mohammad Ehtisham Khan, Mohammad Mansoob Khan, Bong-Ki Min et al.

Scientific Reports • 2018

Abstract This paper reports a simple, biogenic and green approach to obtain narrow band gap and visible light-active TiO 2 nanoparticles. Commercial white TiO 2 ( w -TiO 2 ) was treated in the cathode chamber of a Microbial Fuel Cell (MFC), which produced modified light gray TiO 2 ( g -TiO 2 ) nanoparticles. The DRS, PL, XRD, EPR, HR-TEM, and XPS were performed to understand the band gap decline of g -TiO 2 . The optical study revealed a significant decrease in the band gap of the g -TiO 2 (E g = 2.80 eV) compared to the w -TiO 2 (E g = 3.10 eV). The XPS revealed variations in the surface states, composition, Ti 4+ to Ti 3+ ratio, and oxygen vacancies in the g -TiO 2 . The Ti 3+ and oxygen vacancy-induced enhanced visible light photocatalytic activity of g -TiO 2 was confirmed by degrading different model dyes. The enhanced photoelectrochemical response under visible light irradiation further supported the improved performance of the g -TiO 2 owing to a decrease in the electron transfer resistance and an increase in charge transfer rate. During the TiO 2 treatment process, electricity generation in MFC was also observed, which was ~0.3979 V corresponding to a power density of 70.39 mW/m 2 . This study confirms narrow band gap TiO 2 can be easily obtained and used effectively as photocatalysts and photoelectrode material.

Muhammed Yarub Adnan, Ahmed Hassoon Ali

Defect and Diffusion Forum • 2023

Microbial fuel cells (MFCs) are considered as an economical and sustainable technology for various applications. This study has designed four single-chamber SCMFCs that composed of graphite plates as electrodes and used wastewater as a substrate for microorganisms. In order to evaluate the performance of SCMFC, the experiments were executed in a batch mode over 18 days at various types of salt bridge. Four salt bridges are used namely (KCl, NaCl, KNO 3 , and Cotton Rope). It was found that KCl generated a maximum voltage of 989 mv. The following results were obtained for wastewater investigated parameters: COD = 94%, PO 4 = 88.4%, NO 3 = 88%, TSS = 80%, and Fe = 76%, respectively at 1 M KCl. The experiment was then carried out using different values of KCl (1, 1.5, 2, 3 M). It was found that at a molar concentration of 1.5, 1422 mv of maximum voltage has been generated. Results for wastewater treatment demonstrated that COD of 81%, PO4 of 78.2%, NO3 of 79%, TSS of 80%, and Fe of 84%.

M. I. N. Ma’arof, Girma T. Chala, Saravanan A/l Ravichanthiran et al.

International Journal of Engineering & Technology • 2018

Recently, various steps have been taken to utilize and develop renewable and sustainable form of energies due to the negative impact and dire limitation over continuous dependency on fossil fuel. This paper presents the effects of aluminium mesh on the performance of a MFC. Aluminium mesh with rectangular shape was used as the electrode and experiments were conducted with respect to various types of resistors. The amount of voltages and power density generated were determined. It was found that the increase in bacterial activities resulted in the increment of oxygen supply, therefore, the voltage generated also increased. In addition, the longevity of bacterial activity is dependent on the amount of catalyst. Moreover, it was observed that the performance of aluminium mesh electrode was smaller than that of graphite electrode.

Maria Jose Salar-Garcia, Oluwatosin Obata, Halil Kurt et al.

Microorganisms • 2020

Bacteria are the driving force of the microbial fuel cell (MFC) technology, which benefits from their natural ability to degrade organic matter and generate electricity. The development of an efficient anodic biofilm has a significant impact on the power performance of this technology so it is essential to understand the effects of the inoculum nature on the anodic bacterial diversity and establish its relationship with the power performance of the system. Thus, this work aims at analysing the impact of 3 different types of inoculum: (i) stored urine, (ii) sludge and (iii) effluent from a working MFC, on the microbial community of the anodic biofilm and therefore on the power performance of urine-fed ceramic MFCs. The results showed that MFCs inoculated with sludge outperformed the rest and reached a maximum power output of 40.38 mW·m−2anode (1.21 mW). The power performance of these systems increased over time whereas the power output by MFCs inoculated either with stored urine or effluent decreased after day 30. These results are directly related to the establishment and adaptation of the microbial community on the anode during the assay. Results showed the direct relationship between the bacterial community composition, originating from the different inocula, and power generation within the MFCs.

Payel Choudhury, Biswanath Bhunia, Tarun Kanti Bandyopadhyaya

Journal of Electrochemical Science and Engineering • 2021

This paper focuses on determination of the influence of electrochemically active mi­cro­or­ga­ni­sms on the transmission of electrons from the respiratory enzymes to the electrode and as­sembling of exoelectrogens to the simulated wastewater medium. In this study, the total of eight microorganisms were experimentally tested to exhibit growth and high iron-reducing ability in the absence of mediators. A major connection was observed between the growth and iron-reduction ability of the micro­organism. The growth and iron-reduction ability were monitored experimentally over time. Based on output data, the screening was done among eight different micro­organisms, where Escherichia coli -K-12 was chosen as the most potent micro­organism for its wide application in a microbial fuel cell (MFC). In the present study, various biochemical process factors were optimized statistically using Tagu­chi metho­dology for the rapid development of growth and iron-reducing assay conditions. The design of various experimental trials was carried out using five process factors at three levels with orthogonal arrays (OA) layout of L18. Five process factors, including quantity of lactose, volume of trace element solution, inoculum percentage, pH, and temperature, were taken into consideration as imperative process factors and optimized for evaluation of growth of bacteria and iron reduction ability. The larger-is-best signal to noise (S/N) ratio, together with analysis of variance ANOVA, were used during optimization. Anticipated results demonstrated that the enhanced bacterial growth of 124.50 % and iron reduction ability of 112.6 % can be achieved with 8 g/L of lactose, 2 ml of trace element solution, 4 % (v/v) of inoculum, pH 7, and temperature of 35 oC. Furthermore, the growth and iron reduc­tion time profiles of Escherichia coli-K12 were performed to determine its feasibility in MFC. Open circuit voltage of 0.555 V was obtained over batch study on a single chamber microbial fuel cell (SCMFC).

N. Thepsuparungsikul, T. C. Ng, O. Lefebvre et al.

Water Science and Technology • 2014

The microbial fuel cell (MFC) is an innovative technology for producing electricity directly from biodegradable organic matter using bacteria. Among all the influenceable factors, anode materials play a crucial role in electricity generation. Recently, carbon nanotubes (CNTs) have exhibited promising properties as electrode material due to their unique structural, and physical and chemical properties. In this study, the impacts of CNT types in CNT-based anodes were investigated to determine their effect on both efficiency of wastewater treatment and power generation. The CNTs, namely single-walled CNT with carboxyl group (SWCNT), multi-walled CNT with carboxyl group (MWCNT-COOH) and multi-walled CNT with hydroxyl group (MWCNT-OH) were used to fabricate CNT-based anodes by a filtration method. Overall, MWCNTs provided better results than SWCNTs, especially in the presence of the -OH groups. The highest power and treatment efficiencies in MFC were achieved with an anode made of MWCNT-OH filtered on Poreflon membrane; the open circuit voltage attained was 0.75 V and the maximum power density averaged 167 mW/m2, which was 130% higher than that obtained with plain carbon cloth. In addition, MWCNT-OH is more cost-effective, further suggesting its potential to replace plain carbon cloth generally used for the MFC anode.

Chikashi Sato, N. Evelin Paucar, Steve Chiu et al.

Processes • 2021

In this study, three single-chamber microbial fuel cells (MFCs), each having Pt-coated carbon cloth as a cathode and four bamboo charcoal (BC) plates as an anode, were run in a fed-batch mode, individually and in series. Simulated potato-processing wastewater was used as a substrate for supporting the growth of a mixed bacterial culture. The maximum power output increased from 0.386 mW with one MFC to 1.047 mW with three MFCs connected in series. The maximum power density, however, decreased from 576 mW/m2 (normalized to the cathode area) with one MFC to 520 mW/m2 with three MFCs in series. The experimental results showed that power can be increased by connecting the MFCs in series; however, choosing low resistance BC is crucial for increasing power density.

Arul Devi Ettiyan, Tamilarasan Karuppiah, Shabarish Shankaran et al.

Sustainability • 2024

The wastewater produced by the pharmaceutical industry is highly organic and toxic. Dual-chambered microbial fuel cells (DMFCs) may represent a sustainable solution to process wastewater while simultaneously recovering its energy content. DMFCs are bio-electrochemical devices that employ microorganisms to transform the chemical energy of organic compounds into electrical energy. This study aims to demonstrate the feasibility of a DMFC with a manganese cobalt oxide-coated activated carbon fiber felt (MnCo2O4-ACFF) electrode to treat pharmaceutical industry wastewater (PW) and exploit its energy content. The proposed technology is experimentally investigated considering the effect of the organic load (OL) on the system performance in terms of organic content removal and electricity production. As per the experimental campaign results, the optimum OL for achieving maximum removal efficiencies for total chemical oxygen demand, soluble oxygen demand, and total suspended solids was found to be 2 g COD/L. At this value of OL, the highest current and power densities of 420 mA/m2 and 348 mW/m2 were obtained. Therefore, based on the outcomes of the experimental campaign, the (MnCo2O4-ACFF) electrode DMFC technique was found to be a sustainable and effective process for the treatment and energy recovery from PW.

K Priyanka, A.merline sheela, ILAMATHI R

Research Square • 2021

Abstract In this research, three individual conditions (static, shaking and MFC) were tested for Congo Red decolorization. P.aeruginosa MTCC 2582 has showed 96.1% decolourization under MFC condition with 85% COD reduction for the dye (100 µM). Microbial fuel cell of P.aeruginosa can discharge the dual duty of degrading the recalcitrant dye with power generation. To understand the influence the growth curve, different substrate concentration of glucose (0-20 g/L) were selected to improve the performance of MFC. Results show that a larger open circuit potential of 0.691 V and a maximum power density of 1.9 mW m -2 was possessed for the degradation of 100 µM of dye at 10 g/L of glucose concentration. Further, the selection of optimum concentration of dye (200 µM) increased the open circuit potential to 0.844 V. The degraded metabolites were confirmed using UV-Vis and FTIR analysis. Biofilm formation on anode at optimal glucose concentration was studied by using SEM analysis.

Rusul Muaffaq Khazaal, Zaineb Ziad Ismail

Journal of Engineering • 2020

In this study, a one-dimensional model represented by Butler-Volmer-Monod (BVM) model was proposed to compute the anode overpotential and current density in a mediator-less MFC system. The system was fueled with various organic loadings of real field petroleum refinery oily sludge to optimize the favorable organic loading for biomass to operate the suggested system. The increase in each organic loading showed higher resistance to electrons transport to the anode represented by ohmic loss. On the contrary, both activation and mass transfer losses exhibited a noticeable decrement upon the increased organic loadings. However, current density was improved throughout all increased loads achieving a maximum current density of 5.2 A/m3. The BVM model perfectly expressed the bioelectrochemical reactions in the anodic-chamber. The experimental measurements for all the studied organic loadings agreed with the model predicted values by an estimated determination factor (R2) of 0.96, proving the validity of the proposed mathematical model to express the anodic bioelectrochemical reactions in the MFC. Also, the sustainable power generated from each cycle was evaluated, and it was found that higher sustainable energy can be harvested from higher organic loading 1000 g/L, which achieved maximum sustainable energy of 0.83 W/m3.

Fatemeh Mahmoodzadeh, Nahid Navidjouy, Saber Alizadeh et al.

Research Square • 2023

Abstract Microbial fuel cells (MFCs) have garnered significant interest from researchers as a self-sustaining and environmentally friendly system for the simultaneous treatment of urban and industrial wastewater and production of bioelectricity. The type and material of the electrode are critical factors that can influence the efficiency and energy production of this treatment process, with porosity, surface area, conductivity, and stability being key considerations. In this study, graphite plates and carbon felt were modified through the electrodeposition of nickel followed by the formation of a biofilm, resulting in conductive bio-anode thin film electrodes with enhanced power generation capacity. The structural and morphological properties of the electrode surfaces were characterized using X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), elemental mapping, and field-emission scanning electron microscopy (FE-SEM) techniques. The results confirmed that nickel was successfully doped and that sufficient amounts of microorganisms were attached to the nickel-deposited electrodes, leading to improved electron transfer and increased power generation. To validate this claim, various parameters such as maximum voltage, current density, and power generation were investigated using a dual-chamber MFC equipped with a Nafion 117 membrane and bio-nickel-doped carbon felt (bio-Ni@CF) and bio-nickel-doped graphite plate (bio-Ni@GP) electrodes under constant temperature conditions. The polarization curve obtained during four loading stages using different anode electrodes indicated that the maximum voltage achieved was 468.0 mV using the bio-Ni@CF electrode, representing an increase of 35.0%, 18.37%, and 9.82% compared to the bare GP, bare CF, and bio-Ni@GP electrodes, respectively. The highest power density and current density achieved using the bio-Ni@CF electrode were 130.72 mW/m2 and 760.0 mA/m2, respectively. Furthermore, the modified electrodes demonstrated appropriate stability and resistance during successful runs. These results suggest that nickel-doped carbon-based electrodes can serve as suitable and stable supported catalysts and conductors for improving efficiency and increasing power generation in MFCs.

P. Belleville, P. J. Strong, P. H. Dare et al.

Water Science and Technology • 2011

We describe the operation of a microbial fuel cell (MFC) system operating on a synthetic wastewater (acetic acid), under conditions of increasing nitrogen limitation. Two MFCs were operated under feed conditions which spanned a range of TKN/COD values of 1.6–28 mg/g. Stable operation was observed in all cases, even when no ammoniacal nitrogen was added to the cell. Improved electrochemical performance (measured as power density, W/m2) was observed as nitrogen limitation was imposed on the cells. Even with no ammonium addition, continuous function of the cell was maintained, at levels consistent with operation at balanced nutrient supplementation. The work has implicated biological nitrogen fixation as a potential source of nitrogen within the MFC. Whilst this hypothesis has yet to be confirmed, the work highlights the opportunity for continuous operation of microbial fuel cells utilising wastewaters with extremely low nitrogen levels, present in pulp and paper, pharmaceutical and petrochemical industries. Further, the described increases in some of the electrochemical indices (e.g. power density) under application of nitrogen limitation may provide a new approach to increasing fuel cell performance. Finally, the lack of any need to add supplemental nitrogen to a MFC-based wastewater treatment technology holds potential for significant financial and environmental savings.

Ian D. Deninger, Caitlin J. Shanahan, Ashna K. Sran et al.

ECS Meeting Abstracts • 2022

Incorporating biomimetic polymers to develop a conducting nanocomposite material is a viable solution to address the problematic charge-transfer limitations that are common to carbon-based electrodes. Additionally, the variability associated with reported power density performance is due to the wide variety of carbon electrode functionalization techniques. Therefore, the efficacy of a biomass-based (i.e., polysaccharides and cellulose) electrode is due to the controlled establishment of a porous, non-covalent, polymer network which can serve as a consistent starting material for further functionalization. The scope of this work aims to utilize the existing biopolymer backbone (i.e., agarose, alginate, and cellulose) as a carbon scaffold to selectively control the photochemically initiated radical polymerization of conductive polymer (i.e., aniline, pyrrole) uniformly throughout the composite. Initial results indicate that the photochemically initiated polymerization of polyaniline and polypyrrole improved the efficacy of chain growth and established more uniform distributions of conducting polymer throughout the composite matrix. Current-voltage sweeps (I-V) of electrodes incorporated with polyaniline showed enhanced charge transfer when compared to polypyrrole systems at similar applied potentials. These results indicate that the absolute electron transfer performance is related to the molecular structure of the conductive polymer network. Polyaniline has a greater structural capacity to resonate electron density throughout the conjugated network, despite containing more dielectric material. In addition, the electron transport performance and efficiency of this biomimetic electrode has been shown to depend on the identity of the incorporated photoinitator (i.e., Fe 3+ ), as well as the type of dopant (i.e., hydrochloric acid, sulfuric acid, polyelectrolyte), and surrounding polymer backbone (i.e., alginate, agarose, cellulose). Preliminary findings on dopant effects indicated markedly faster rates of charge transfer in electrodes doped with sulfuric acid. Furthermore, an extension of these enhanced current-voltage properties has been applied into a mediator-less E. coli MFC system, which exhibited increased open circuit potentials comparable to carbon cloth.

Waheed Miran, Mohsin Nawaz, Jiseon Jang et al.

RSC Advances • 2015

The effect of wastewater containing MWCNTs on MFC performance was evaluated. MWCNTs addition resulted in a higher voltage/power density generation and COD/TOC removal. Low LDH release and a compact biofilm showed insignificant electricigen damage.

Joseph Kidehu, John Geophrey

Tanzania Journal of Engineering and Technology • 2018

Experimental study was undertaken to evaluate performance of microbial fuel cell. Without addition of methyl blue, the cell generated 1.265 V, 0.403 mA and 56.12 mW/m2 after three hours of operation. With 300 µM methyl blue in sewage anolyte, 6.7% increase in voltage, 20.5% increase in current and 28.6% increase in power density was observed. By using ash- water catholyte, addition of methyl blue in anolyte led to increase of 9.0% in voltage, 38.5% in current and 50.9% for power density. Between three and twenty four hours of continuous operation of the cell with phosphate buffer catholyte, the average voltage was 1.305 V and the average current was 0.321 mA before addition of methyl blue. Methyl blue addition led to 5.1% increase in voltage and 55.2% increase in current. For the case of ash-water catholyte with methyl blue in anolyte, led to 6.2% increase in voltage and 59.1% increase in current.

Hassan Ali Ozgoli, Sara Deilami

Journal of Electronics and Electrical Engineering • 2024

This research introduces an innovative integration of a Polymer Electrolyte Membrane Fuel Cell (PEMFC) with a Combined Heat and Power (CHP) system utilizing autothermal reforming (ATR) of natural gas. This novel approach focuses on large-scale industrial applications, addressing scalability and performance optimization, areas previously underexplored. The study conducts a comprehensive parametric analysis of system efficiency, achieving a remarkable 91.3% total efficiency, with 38.1% electrical efficiency and 46.1% thermal efficiency. Economic analysis revealed strong regional differences, with Europe offering the highest Net Present Value (NPV) and a payback period of 4.0 years, while Iran showed a longer payback period of 8.3 years. The system demonstrated adaptability to fluctuating electricity prices, particularly in the U.S. Environmentally, the system achieved a 50% reduction in CO2 emissions and reduced natural gas consumption compared to conventional gas turbines. This innovative study addresses scalability challenges and offers new insights into optimizing PEMFC-CHP systems for sustainable industrial energy generation, contributing to the advancement of clean energy technologies.

Rui Sun, Qianyong Zhang, Zhirao Yin et al.

Academic Journal of Science and Technology • 2024

In this paper, phosphoric acid, nitric acid, zinc chloride, ammonia and melamine are used as cheaper activators to modify the carbon felt material, exploring the changes of various activation materials on the power production performance and degradation performance of the device after MFC carbon felt anode treatment, and finding that phosphoric acid-activated carbon felt has the highest output voltage and the best degradation effect on the ship's oily wastewater as a MFC anode device.

Tesfalem Atnafu, Seyoum Leta

Environmental Systems Research • 2021

Abstract Background Microbial fuel cell (MFC) technology is a promising sustainable future energy source with a renewable and abundant substrate. MFC critical drawbacks are anode surface area limitations and electrochemical loss. Recent studies recommend thick anode biofilm growth due to the synergetic effect between microbial communities. Engineering the anode surface area is the prospect of MFC. In this study, a microbial electrode jacket dish (MEJ-dish) was invented, first time to the authors’ knowledge, to support MFC anode biofilm growth. The MFC reactor with MEJ-dish was hypothesized to develop a variable biofilm thickens. This reactor is called a fragmented electro-active biofilm-microbial fuel cell (FAB-MFC). It was optimized for pH and MEJ-dish types and tested at a bench-scale. Results Fragmented (thick and thin) anode biofilms were observed in FAB-MFC but not in MFC. During the first five days and pH 7.5, maximum voltage (0.87 V) was recorded in MFC than FAB-MFC; however, when the age of the reactor increases, all the FAB-MFC gains momentum. It depends on the MEJ-dish type that determines the junction nature between the anode and MEJ-dish. At alkaline pH 8.5, the FAB-MFC generates a lower voltage relative to MFC. On the contrary, the COD removal was improved regardless of pH variation (6.5–8.5) and MEJ-dish type. The bench-scale studies support the optimization findings. Overall, the FAB improves the Coulombic efficiency by 7.4–9.6 % relative to MFC. It might be recommendable to use both FAB and non-FAB in a single MFC reactor to address the contradictory effect of increasing COD removal associated with the lower voltage at higher pH. Conclusions This study showed the overall voltage generated was significantly higher in FAB-MFC than MFC within limited pH (6.5–7.5); relatively, COD removal was enhanced within a broader pH range (6.5–8.5). It supports the conclusion that FAB anode biofilms were vital for COD removal, and there might be a mutualism even though not participated in voltage generation. FAB could provide a new flexible technique to manage the anode surface area and biofilm thickness by adjusting the MEJ-dish size. Future studies may need to consider the number, size, and conductor MEJ-dish per electrode.

Fernando A. Rojas, Carlos Hernández‐Benitez, Víctor Ramírez et al.

Fuel Cells • 2024

Abstract Some of the most popular technologies for wastewater sanitation, still face serious limitations related to high energy consumption requirements. In this context, microbial fuel cells (MFCs) constitute a promising approach since they do not require aeration and produce electricity at the same time. Limitations for these devices, however, are related to the cost of the constituents and the functionality of the arrangement. In this work, a semi‐cylindrical ceramic MFC was designed and constructed using a low‐cost commercial ceramic handcraft as a membrane, carbon felt, carbon cloth, and carbon cloth/activated carbon in different arrangements for the anode and cathode components. The best results were obtained using carbon felt as an anode and a cathodic zone built with carbon felt in which void regions were filled with activated carbon. This arrangement produced 85 mWm −2 for each cell. Evaluating the performance of the MFC in a modular system with eight cells using a different number of separations inside the module and different electrical connections, resulting in a 4‐compartment module that produced 90 mWm −2 with one single module and 95 mWm −2 with a serial arrangement of two modules.