Adrianna Nogalska, Andreu Bonet Navarro, Ricard Garcia-Valls

Membranes • 2020

Membrane electrode assemblies (MEAs) with palladium catalysts were successfully prepared by using a home-made manual pressing system with Nafion glue application that contributed to a decrease of additional energy consumption. The catalyst coated membranes were prepared with supported palladium on activated carbon (PdC) and unsupported palladium black (PdB) for comparison. The performance of passive, air breathing, functioning under ambient conditions and with low concentration (1 M) formate/formic acid fuel cell was evaluated. Based on polarization curves, the best result was obtained with carbon supported catalyst and HCOOK fuel, achieving 21.01 mW/mgPd. Still, constant current discharge with PdC showed an energy generation efficiency of 14% with HCOOH over 3% with HCOOK caused by lower potassium ion conductivity and its permeability through the proton exchange membrane. The faradic efficiency of conversion in the cell is equal to the overall energy efficiency and makes the cell self-sufficient.

Melisa Acosta-Coll, Adalberto Ospino-Castro, Stalin Carbonell-Navarro et al.

Preprints.org • 2019

Plants Microbial Fuel Cells (PMFC) is a new technology that generates electricity in a renewable, clean and sustainable way. In spite of these advantages, it still faces limitations in power generation and current density, reaching lower production values than other renewable technologies. Different studies maintain that the high resistivity of the cathode is the main limitation in the generation of energy; therefore, non-metallic materials to obtain a better performance are replacing the metallic electrodes. The implementation of these materials applied to PMFC requires a complex interdisciplinary work. Through three experimental tests using metallic electrodes for the extraction of electrons, this research study shows that the treatment of the substrate with natural materials, the volume plant roots, and substrate temperature and humidity control have a significant influence in the increase of the electric potential and the generated current.

Mohammed Yousri Silaa, Mohamed Derbeli, Oscar Barambones et al.

Sustainability • 2021

Taking into account the restricted ability of polymer electrolyte membrane fuel cell (PEMFC) to generate energy, it is compulsory to present techniques, in which an efficient operating power can be achieved. In many applications, the PEMFC is usually coupled with a high step-up DC-DC power converter which not only provides efficient power conversion, but also offers highly regulated output voltage. Due to the no-linearity of the PEMFC power systems, the application of conventional linear controllers such as proportional-integral (PI) did not succeed to drive the system to operate precisely in an adequate power point. Therefore, this paper proposes a robust non-linear integral fast terminal sliding mode control (IFTSMC) aiming to improve the power quality generated by the PEMFC; besides, a digital filter is designed and implemented to smooth the signals from the chattering effect of the IFTSMC. The stability proof of the IFTSMC is demonstrated via Lyapunov analysis. The proposed control scheme is designed for an experimental closed-loop system which consisted of a Heliocentric hy-Expert™ FC-50W, MicroLabBox dSPACE DS1202, step-up DC-DC power converter and programmable DC power supplies. Comparative results with the PI controller indicate that a reduction of 96% in the response time could be achieved using the suggested algorithm; where, up to more than 91% of the chattering phenomenon could be eliminated via the application of the digital filter.

David M. Mackie

• 2016

Applications for bio-hybrid fuel cells (BHFCs) and other weak energy sources would greatly benefit from highly-efficient power compression that substantially increased the voltage and also allowed intermittent draws of high current. The assumption of a weak energy source necessitates also minimizing parasitic energy draws. We present results for a power compressor composed of a boost converter (variable voltage upconversion), a harvest regulator (matching impedances on the fly), and a bank of low-leakage capacitors (high current draw for short times). The power compressor was not externally powered. Performance was evaluated while connected to two direct ethanol fuel cells (DEFCs) in series, for periods of 3 and 10 days. The DEFCs' design was not optimized for power. They were non-flowing, room-temperature, air-cathode, PtRu/Pt units, which simulated the output of small BHFCs. The power compressor automatically kept the DEFCs close to the voltage yielding maximum power output, which was 400 mV for two DEFCs in series. The output voltage of the capacitor bank was repeatedly raised to 10.25 V and then discharged to 5 V through a resistor. Energy efficiency of the power compressor was uniformly 50%, except for very weak input power.

Yuyang Wang

Coatings • 2024

Anode materials play a crucial role in the performance of microbial fuel cells (MFCs) in terms of power output. In this study, carbon nanotube (CNT)/polyaniline (PANI)/chitosan (CS) composites were prepared on a porous sponge matrix. The high electrical conductivity of CNTs, the capacitive behavior of PANI, and the biocompatibility of CS were leveraged to enhance the electricity generation and energy storage capabilities of MFCs. Experimental results demonstrated that the MFC with the modified anode achieved a maximum power density of 7902.4 mW/m3. Moreover, in the charging–discharging test, the stored electricity of the S/CNT/PANI/CS anode was 16.38 times that of the S/CNT anode when both the charging and discharging times were 30 min. High-throughput sequencing revealed that the modified composite anode exhibited remarkable biocompatibility and selective enrichment of electrogenic bacteria. Overall, this study presents a novel approach for developing composite MFC anode materials with energy storage functionality.

A. Janicek, N. Gao, Y. Fan et al.

Fuel Cells • 2015

Abstract Replacing precious metal catalysts by inexpensive activated carbon (AC) is a breakthrough in microbial fuel cell (MFC) cathode fabrication. In this study, AC powders made from bamboo, peat, coal, coconut, and hardwood sources are evaluated in terms of their electrochemical performance with carbon cloth as the base material. These ACs are characterized in terms of their conductivity, surface chemistry, surface area, and pore size distribution. The bamboo‐based AC demonstrates the highest potential for use as a catalyst for carbon cloth based cathode, reaching 10.6 A m −2 at 0V vs. Ag/AgCl and a loading of 25 mg cm −2 . The maximum power density reached 3.3 W m −2 in CEA–MFCs. The high performance of the bamboo‐based AC cathode was possible due to the good conductivity and suitable surface chemistry of the bamboo AC and the high surface area of the base material. The hydrostatic pressure tolerance of the AC carbon cloth cathode is greater than 1.8 m, allowing for a more versatile cathode, suitable for use in many different reactor configurations.

A. Jamekhorshid, G. Karimi, X. Li

ASME 2009 7th International Conference on Fuel Cell Science, Engineering and Technology • 2008

Non-uniform current distribution in polymer electrolyte membrane fuel cells results in local over-heating, accelerated ageing, and lower power output than expected. This issue is very critical when fuel cell experiences water flooding. In this work, the performance of a PEM fuel cell is investigated under cathode flooding conditions. A partially flooded GDL model is proposed to study local current density distributions along flow fields over a wide range of cell operating conditions. The model results show as cathode inlet humidity and/or cell pressure increase the average current density for the unflooded portions of the cell increases but the system becomes more sensitive to flooding. Operating the cell at higher temperatures would lead to higher average current densities and the chance of system being flooded is reduced. In addition, higher cathode stoichiometries prevent system flooding but the average current density remains almost constant.

Imologie Meshack Simeon, Alfons Weig, Ruth Freitag

Biotechnology for Biofuels and Bioproducts • 2022

Abstract Background Microbial fuel cells (MFCs) are among the leading research topics in the field of alternative energy sources due to their multifunctional potential. However, their low bio-energy production rate and unstable performance limit their application in the real world. Therefore, optimization is needed to deploy MFCs beyond laboratory-scale experiments. In this study, we investigated the combined influence of electrode material (EM), electrode spacing (ES), and substrate feeding interval (SFI) on microbial community diversity and the electrochemical behavior of a soil MFC (S-MFC) for sustainable bio-electricity generation. Results Two EMs (carbon felt (CF) and stainless steel/epoxy/carbon black composite (SEC)) were tested in an S-MFC under three levels of ES (2, 4, and 8 cm) and SFI (4, 6, and 8 days). After 30 days of operation, all MFCs achieved open-circuit voltage in the range of 782 + 12.2 mV regardless of the treatment. However, the maximum power of the SEC–MFC was 3.6 times higher than that of the CF–MFC under the same experimental conditions. The best solution, based on the interactive influence of the two discrete variables, was obtained with SEC at an ES of 4.31 cm and an SFI of 7.4 days during an operating period of 66 days. Analysis of the experimental treatment effects of the variables revealed the order SFI < ES < EM, indicating that EM is the most influential factor affecting the performance of S-MFC. The performance of S-MFC at a given ES value was found to be dependent on the levels of SFI with the SEC electrode, but this interactive influence was found to be insignificant with the CF electrode. The microbial bioinformatic analysis of the samples from the S-MFCs revealed that both electrodes (SEC and CF) supported the robust metabolism of electroactive microbes with similar morphological and compositional characteristics, independent of ES and SFI. The complex microbial community showed significant compositional changes at the anode and cathode over time. Conclusion This study has demonstrated that the performance of S-MFC depends mainly on the electrode materials and not on the diversity of the constituent microbial communities. The performance of S-MFCs can be improved using electrode materials with pseudocapacitive properties and a larger surface area, instead of using unmodified CF electrodes commonly used in S-MFC systems.

Leyuan Zhang, Yucheng Zhang, Yang Liu et al.

ChemRxiv • 2024

Microbial fuel cells (MFCs) utilize exoelectrogenic microorganisms to directly convert organic matter into electricity, offering a compelling approach for simultaneous power generation and wastewater treatment. However, conventional MFCs typically require thick biofilms for sufficient metabolic electron production rate, which inevitably compromises mass and electron transport, posing a fundamental tradeoff of limiting the achievable power density (<1 mW cm-2). Herein, we report a new concept of redox mediated microbial flow fuel cells (MFFCs) by exploiting artificial redox mediators in flowing medium to efficiently transfer metabolic electrons from bacteria to electrodes, which effectively overcomes mass transport limitations and markedly reduces internal resistance. The biofilm-free MFFC thus breaks the inherent tradeoff in dense biofilms, resulting in a maximum current density surpassing 40 mA cm-2 and a highest power density exceeding 10 mW cm-2, approximately one order of magnitude higher than those of state-of-the-art MFCs, to the best of our knowledge.

Hoang Dung Nguyen, Sandhya Babel

Suranaree Journal of Science and Technology • 2024

This study explores the utilization of a cation exchange membrane (CEM) in a microbial fuel cell (MFC) system to isolate nitrogen from wastewater influents. While employing a CEM in an MFC system has drawbacks, such as increased internal resistance and reduced power output, it also provides a means for optimal energy recovery from organics while allowing isolated nitrogen to be treated in subsequent steps. This study evaluated the diffusion of ammonium through CEM in a dual-chamber MFC under different operating conditions. Results indicated that the MFC reactor with CEM as a separator isolated 88-93% of the nitrogen input, demonstrating the feasibility of this approach for nitrogen separation in wastewater treatment applications. Factors affecting nitrogen isolation, including COD input at the anode, dissolved oxygen (DO) at the cathode, and external resistance (ER), are identified. Higher COD input at the anode and the DO at the cathode were found to enhance nitrogen separation, while increased ER had an adverse effect on nitrogen isolation capacity. Additionally, changes in the surface characteristics of the CEM during operation could impact nitrogen isolation, emphasizing the need for careful monitoring and maintenance of the CEM to ensure consistent performance over time. In conclusion, this study highlighted the potential of using a CEM in MFC systems for nitrogen isolation, provided insights into the factors affecting the efficacy of nitrogen separation, and underscored the need for monitoring and maintenance of the CEM. These results could significantly impact the development of more efficient and sustainable wastewater treatment using the MFC system.

Mustapha Abdeldjabar Charef, Hakima Kebaili, Mostefa Kameche et al.

Indonesian Journal of Chemistry • 2021

A Microbial Fuel Cell (MFC) was conceived by using garden soil as a source to culture. It was then utilized as a bio-catalyst to decompose waste organic matter, reduce pollution from the soil, and produce energies. The MFC was composed of a bio-anode inoculated with a mixture of garden compost leachate and an abiotic stainless steel cathode. Besides, the bio-anode consisted of a Nafion membrane modified with carbon. The microorganisms agglomerated under polarization and formed electroactive bio-film onto bio-anode. In the preliminary test of MFC, potassium hexacyanoferrate has been utilized as catholyte, to enhance the reduction of proton and electrons resulting in a higher voltage. However, this electrolyte is toxic and oxidized rapidly, thus substituted by the hydrochloric acid. The results showed that the MFC with modified Nafion, gave relatively high current-density 379 mA/m2 in two days, whereas the conventional biofuel cell without modification attained the current-density 292 mA/m2 in four days. Nevertheless, both cells yielded almost the same current density of 20 mA/m2 during 60 days. Although it has been used for a long time, the modified Nafion has not been corroded and preserved its physicochemical properties.

Aleksandrs Andreiciks, Ingars Steiks, Oskars Krievs

Scientific Journal of Riga Technical University. Power and Electrical Engineering • 2009

Current-fed Step-up DC/DC Converter for Fuel Cell Applications with Active Overvoltage Clamping In order to use hydrogen fuel cells in domestic applications either as main power supply or backup source, their low DC output voltage has to be matched to the level and frequency of the utility grid AC voltage. Such power converter systems usually consist of a DC-DC converter and a DC-AC inverter. A double inductor step-up push-pull converter is investigated in this paper, presenting simulation and experimental results for passive and active overvoltage clamping. The prototype of the investigated converter is elaborated for 1200 W power to match the rated power of the proton exchange membrane (PEM) fuel cell located in hydrogen fuel cell research laboratory.

Yuyang Wang, Guangxu Hu, Jing Dong et al.

Coatings • 2023

Microbial fuel cells (MFCs) have shown promise in solving energy and environmental problems, but their practical application is limited by their low power output. In this study, carbon nanotubes/polypyrrole composite anode materials were prepared on a porous sponge matrix. By combining the porous characteristics of sponge, the good conductive properties of carbon nanotubes, and the energy storage ability of polypyrrole capacitive materials, the prepared anode exhibited a large specific capacity, high porosity, large specific surface area, good electron transport ability, and good biocompatibility. The results showed that the maximum power density of the modified anode MFC reached 7.46 W m−3, which was 2.53 times higher than that of the control anode. The stored energy Qs released by the modified anode was 235.6 C m−2, 6.5 times higher than that of the control electrode. In addition, the transfer impedance Rct of the S/CNT/PPy electrode (5.5 Ω) was much lower than that of the control anode (16.8 Ω). The research presented in this paper demonstrates a new approach to improving the power generation ability and energy storage performance of MFCs.

Nhlanganiso Ivan Madondo, Sudesh Rathilal, Babatunde Femi Bakare et al.

Molecules • 2023

A microbial fuel cell (MFC) is a bioelectrochemical system that can be employed for the generation of electrical energy under microbial activity during wastewater treatment practices. The optimization of electrode spacing is perhaps key to enhancing the performance of an MFC. In this study, electrode spacing was evaluated to determine its effect on the performance of MFCs. The experimental work was conducted utilizing batch digesters with electrode spacings of 2.0 cm, 4.0 cm, 6.0 cm, and 8.0 cm. The results demonstrate that the performance of the MFC improved when the electrode spacing increased from 2.0 to 6.0 cm. However, the efficiency decreased after 6.0 cm. The digester with an electrode spacing of 6.0 cm enhanced the efficiency of the MFC, which led to smaller internal resistance and greater biogas production of 662.4 mL/g VSfed. The electrochemical efficiency analysis demonstrated higher coulombic efficiency (68.7%) and electrical conductivity (177.9 µS/cm) for the 6.0 cm, which was evident from the enrichment of electrochemically active microorganisms. With regards to toxic contaminant removal, the same digester also performed well, revealing removals of over 83% for chemical oxygen demand (COD), total solids (TS), total suspended solids (TSS), and volatile solids (VS). Therefore, these results indicate that electrode spacing is a factor affecting the performance of an MFC, with an electrode spacing of 6.0 cm revealing the greatest potential to maximize biogas generation and the degradability of wastewater biochemical matter.

Doug Aaron, Costas Tsouris, Choo Y. Hamilton et al.

Energies • 2010

Impedance changes of the anode, cathode and solution were examined for an air-cathode microbial fuel cell (MFC) under varying conditions. An MFC inoculated with a pre-enriched microbial culture resulted in a startup time of less than ten days. Over this period, the anode impedance decreased below the cathode impedance, suggesting a cathode-limited power output. Increasing the anode flow rate did not impact the anode impedance significantly, but it decreased the cathode impedance by 65%. Increasing the anode-medium ionic strength also decreased the cathode impedance. These impedance results provide insight into electron and proton transport mechanisms and can be used to improve MFC performance.

Giulia Massaglia, Tommaso Serra, Candido Fabrizio Pirri et al.

Preprints.org • 2023

This work investigates a new nanostructured gas-diffusion-layer (nano-GDL) to improve performance of air-cathode Single-Chamber-Microbial-Fuel-Cells (a-SCMFCs). The new nano-GDLs improves the direct oxygen-reduction-reaction by exploiting the best of nanofibers from electrospinning in terms of high surface ratio to volume and high porosity, and laser-based processing to promote adhesion. Nano-GDLs by electrospinning were fabricated directly collecting two nanofibers mats on the same carbon-based electrode, acting as the substrate. Each layer was designed with a specific function: water resistant, oxygen permeable polyvinylidene-difluoride (PVDF) nanofibers served as a barrier to prevent water-based electrolyte leakage, while an inner layer of cellulose nanofibers was added to promote oxygen diffusion towards the catalytic sites. The maximum current density obtained for a-SCMFCs with the new nano-GDLs is (132.2 ± 10.8) mA m-2, and it doubles the current density obtained with standard PTFE-based GDL (58.5 ± 2.4 mA m-2), used as reference material. The energy recovery (EF) factor, i.e. the ratio of the power output to the inner volume of the device, was then used to evaluate the overall performance of a-SCMFCs. a-SCMFCs with nano-GDL provided an EF value of 60.83 mJ m-3: one order of magnitude higher than the value of 3.92 mJ m-3 obtained with standard GDL

Yubing Pan, Junping Xiang, Yanan Li et al.

Fuel Cells • 2024

ABSTRACT Microbial electrolysis cells (MECs) can effectively treat sulfate‐containing wastewater, but biocathode microorganisms, such as sulfate‐reducing bacteria (SRB), are susceptible to environmental influences. In practical wastewater treatment, the flow of water in the reactor generates shear forces that directly impact the growth and structure of the biofilm, which leads to changes in MEC efficacy. However, the sulfate reduction efficacy and biofilm community structure changes in MEC reactors under flow conditions have yet to be adequately evaluated. In this study, two‐chamber SRB biocathode MECs were constructed under flow conditions (experimental group [EG]) and stationary conditions (control group [CG]). The sulfate reduction rates of CG and EG were stable and reached 88.9% and 84.45%, respectively. The output voltage and current density of EG were similar to those of CG, indicating that the MEC could operate stably under flow conditions. The community structure of the biocathode indicated a high relative abundance of Desulfomicrobium from EG, which promoted the dissimilatory sulfate reduction pathway. This information reveals the potential of flow in improving the performance of MECs in treating sulfate‐containing wastewater.

Aleksandrs Andreičiks, Kristaps Vitols, Oskars Krievs et al.

Scientific Journal of Riga Technical University. Power and Electrical Engineering • 2008

Current Fed Step-up DC/DC Converter for Fuel Cell Inverter Applications In order to use hydrogen fuel cells in domestic applications either as main power supply or backup source, their low DC output voltage has to be matched to the level and frequency of the utility grid AC voltage. Such power converter systems usually consist of a DC-DC converter and a DC-AC inverter. Comparison of different current fed step-up DC/DC converters is done in this paper and a double inductor step-up push-pull converter investigated, presenting simulation and experimental results. The converter is elaborated for 1200 W power to match the rated power of the proton exchange membrane (PEM) fuel cell located in hydrogen fuel cell research laboratory of Riga Technical University.

Kalpana Sharma, Vandana Singh, Soumya Pandit et al.

Sustainability • 2022

Biosurfactant-producing microorganisms improve the efficacy of hydrocarbon biodegradation as the biosurfactant is essential in making hydrocarbons available for breakdown. The present study reports the isolation of biosurfactant-producing bacteria that can be used for crude oil remediation and to characterize the biosurfactant generated during the breakdown of crude oil. This study also reports evaluating the synergism and potentiality of biosurfactant-producing bacteria for simultaneous hydrocarbon biodegradation and power generation. Two bacterial strains (Bacillus subtilis strain B1 and Pseudomonas aeruginosa strain B2) were isolated from petroleum-contaminated soils, which are found effective in producing biosurfactants and degrading crude oil as the sole carbon source. B. subtilis B1 exhibited a higher potential for biosurfactant production and crude oil degradation than P. aeruginosa B2. The FTIR and GC-MS analysis were conducted for further characterization of the biosurfactant, which revealed that the surfactant produced by strain B1 and B2 was surfactin and rhamnolipid, respectively. The application of the B1 and B2 co-culture in microbial fuel cells (MFCs) showed synergism among them and resulted in a maximum power density production of 6.3 W/m3 with an open circuit voltage of 970 mV while degrading 2.5% v/v crude oil containing anolyte. The findings indicate that the co-culture of isolated crude oil-degrading strains has great potential for enhanced power generation and the bioremediation of hydrocarbon-contaminated environments. Moreover, the synergism of isolated strains in MFCs suggested their potent applicability in environmental, energy, and industrial sectors as an economical and feasible alternative to the existing technologies.

Rihab. Jaralla

• 2021

A novel mathematical model for an entire proton exchange membrane fuel cell (PEMFC) is developed with its focus placed on the modeling and assessment of thermodiffusion effects that have been neglected in previous studies. Instead of treating catalyst layers as interfaces of nil thickness, the model presented here features a finite thickness employed for catalyst layers, allowing for a more realistic description of electrochemical reaction kinetics arising in the operational PEMFC. To account for the membrane swelling effect, the membrane water balance is modeled by coupling the diffusion of water, the pressure variation, and the electro-osmotic drag. The complete model consisting of the equations of continuity, momentum, energy, species concentrations, and electric potentials in different regions of a PEMFC are numerically solved using the finite element method implemented into a commercial CFD (Comsol 3.4) code. Various flow and transport phenomena in an operational PEMFC are simulated using the newly developed model. The resulting numerical simulations demonstrate that the thermodiffusion has a noticeable impact on the mass transfer for the oxygen. It is also revealed through a systematic parametric study that, as the porosity of gas diffusion layers and catalyst layers increase, the current density of an operational PEMFC may increase. Also, it is found that a PEM fuel cell can perform better with reasonable high operating pressure and temperature, as well as a supply of fully humidified gaseous reactants.

J. B. Costa Santos, V. V. Silva de Barros, J. J. Linares

Fuel Cells • 2018

Abstract This study focuses on the influence of sludge age (SA) on the production of electricity from a cyclically fed glycerol–based microbial fuel cell. Under the same hydraulic retention time, different volumes of sludge were extracted from the anode compartment, thereby modifying the SA. Such changes affect the electrochemical performance, the organic matter biodegradation and consequently, the coulombic efficiency. A sludge volume of 0.01 L (corresponding to a SA of 24 d) appears to be optimal, because this favors the development of electricity–generating microorganisms (EGM). Shorter SA times wash EGM out of the system and promote growth of the fermenter (mainly acidogenic bacteria), whereas a longer SA reduces the microbial population. A final product analysis identified that short SAs provide favorable conditions in which higher concentrations of short–chain organic acids are detected.

Suhad Shamil Jaroo, Ghufran Farooq Jumaah, Talib Rashid Abbas

Journal of Engineering • 2021

A microbial desalination cell (MDC) is a new approach to bioelectrochemical systems. It provides a more sustainable way to electrical power production, saltwater desalination, and wastewater treatment at the same time. This study examined three operation modes of the MDC: chemical cathode, air cathode, and biocathode MDC, to give clear sight of this system's performance. The experimental work results for these three modes were recorded as power densities generation, saltwater desalination rates, and COD removal percentages. For the chemical cathode MDC, the power density was 96.8 mW/m2, the desalination rate was 84.08 ppm/hr, and the COD removal percentage was 95.94%. The air cathode MDC results were different; the power density was 24.2 mW/m2, the desalination rate was 86.11 ppm/hr, and the COD removal percentage was 91.38%. The biocathode MDC results were 19.91 mW/m2 as the power density, 88.9 ppm/hr as the desalination rate, and 96.94% as the COD removal percentage. The most efficient type of MDC in this study in power production was the chemical cathode MDC, but it is the lowest sustainable. On the other hand, the biocathode MDC was the best in desalination process performance, and both the air cathode and biocathode MDC are more sustainable and environmentally friendly, especially the biocathode MDC.

Nazish Manzoor, Zulqarnain, M. Anees et al.

Latin American Applied Research - An international journal • 2021

Due to the global energy crisis in the world and no proper utilization of renewable and non-renewable resources, different experimental design approaches and substrates have been employed to produce bioelectricity in an MFC. The major substrate that has been tried to focus in this review paper is carboxymethyl cellulose (CMC). Carboxymethyl cellulose is an important factor in Microbial fuel cell with great importance in industry. No known enzyme is directly involved in the oxidation/reduction of CMC, however, carboxymethyl cellulases attack, specifically CMC. Moreover, our knowledge on electrochemically active bacteria is inadequate. Although, knowledge about electrochemically active bacteria is inadequate, distinct cellulose degrading bacteria have been isolated for their higher cellulase activity. Similarly, pure bacterial cultures and co-cultures have been extensively used in degrading CMC for power and electricity generation. CMC concentration and effect of different substitution factors also play an important role in voltage generation. Different ways to make enzymatic electrode for current production using CMC fed reactor were also discussed in this study. This review gives an overview about the current developments of CMC being used as substrate in MFCs and encourages to develop more efficient processes for improved bioelectricity production in MFCs.

Jain Suransh, Alok Kumar Tiwari, Arvind Kumar Mungray

Environmental Progress & Sustainable Energy • 2020

Abstract The aim of this study was to develop an economically viable clayware ceramic membrane that exhibits proton mass transfer comparable to the commercially available membrane (Nafion 117) for microbial fuel cell (MFC). The clayware ceramic membrane made from red soil was modified using cation exchangers like montmorillonite (MMT) and vermiculite (VC), and by spray coating of MMT composite with Nafion solution. Nafion‐117 (a commercial membrane) and membrane prepared using only red soil were used as a standard and control, respectively. Other membranes include 20% blend of MMT with red soil (SM); 20% VC with red soil (SV); 10% blend of each MMT and VC with red soil (SMV); and SM membrane spray‐coated with Nafion solution (SMN). The addition of cation exchangers enhances the performance of the clayware ceramic membranes as compared to the control, and coating of Nafion solution on SMN leads it to perform even better. Average open circuit voltage and average operating voltage for the SMN membranes were 670 ± 17.63 mV and 82 ± 5.69 mV, respectively, which are the best among all the fabricated membranes. The power density of the SMN membrane was 84.3 mW/m 3 which is five times that of the control. The study demonstrates that SMN membrane can be used as an alternate for more costly polymeric membranes in MFC.

Thi Hiep Han, Sandesh Y. Sawant, Sun-Jin Hwang et al.

RSC Advances • 2015

Microbial fuel cell based on as-prepared N-doped carbon foam produced 2 times higher power density than the commercial graphite felt.

Guorong Xie, Chansoo Choi

Bulletin of the Korean Chemical Society • 2020

Metal complex‐microbial fuel cells (MFCs) have been investigated in this work with intent manufacturing highly efficient MFC batteries. The performance of metal complex MFCs was evaluated by polarization and discharge experiments using a battery consisting of three MFC unit cells. The results indicated that the performance of the [Fe(III)(4,4′‐dimethyl‐2,2′‐bipyridyl) 3 ]‐MFC was much better than the other MFC containing Cr(VI) or Fe(III) as an electron acceptor. At a discharging current of 3 mA (17.6 A/m 3 ), the average discharging potential was found to be 0.927 V under a parallel‐connection, sustaining longer than 20 h with an open circuit voltage of 1.210 V. [Fe(III)(4,4′‐dimethyl‐2,2′‐bipyridyl) 3 ]‐MFC showed much higher electrochemical parameters than Cr(VI)‐MFC and Fe(III)‐MFC. Highest maximum power of 34.87 Wm −3 could be obtained from the battery consisting of three MFCs in parallel‐connection, when each cell contains a carbon brush anode and a graphite plate. MFC battery containing a carbon brush anode and a carbon brush cathode showed better polarization and discharging performance. In particular, the maximum power of 45.45 Wm −3 was achieved. By installing the maximum amount of carbon brush anode and adjusting the amount of carbon brush cathode and the electron acceptors, the magnitude of current and the maximum power can be maximized.

J. A. Cano‐López, D. Ortega‐Díaz, A. Duarte‐Moller et al.

Fuel Cells • 2018

Abstract This paper describes the construction of 3D‐printed current collectors used in the fabrication, simulation and performance evaluation of four mini proton exchange membrane (PEM) fuel cells. These fuel cells comprised of acrylonitrile butadiene styrene‐printed current collector plates using different flow channel designs: pin, spiral, serpentine and radial. In this work, we demonstrated that the mini PEM fuel cells were capable of converting fuel to current according to computational fluid dynamics, which was used to carry out the optimization of the geometry of the current collector plates. The correlation between the mass transfer and the power density is discussed, and the largest mass transfer is reported for the pin geometry, which also yielded the higher power values compared to the spiral, serpentine and radial geometries (9.9, 9.0, 9.0, and 8.2 mW cm −2 , respectively). These low‐cost devices should be useful for portable applications.

J. M. Moon, S. Kondaveeti, B. Min

Fuel Cells • 2014

Abstract We compared novel size‐selective separators, namely the textile fabrics of polyphenylene sulfide (PPS) and sulfonated polyphenylene sulfide (S‐PPS), and the nonwoven fabrics of polypropylene80 (PP 80) and PP 100, with commonly used ion exchange separators (Nafion 117 and cation exchange membane‐7000; CMI‐7000) in terms of power generation, oxygen diffusion, and biofilm formation in a single chamber microbial fuel cell. Size‐selective separators exhibited more power generation than ion selective separators. MFC operation with size‐selective separators generated power output ranging 0.407 to 0.591 V (1000 Ω), whereas with Nafion it was 0.272 V. In polarization analysis, S‐PPS resulted in the highest power density of 190 mW/m 2 , whereas it was 24 mW/m 2 with Nafion‐117. Size selective separators showed similar or higher proton conductivity than Nafion 117. Oxygen mass transfer coefficients of size‐selective separators (K O = 3.7 ∼ 7.5 × 10 −5 ) were lower or similar to Nafion (K O = 7.5 × 10 −5 ). Fourier‐transform infrared spectroscopy and scanning electron microscopy analysis revealed that all separators (PP80, S‐PPS, and Nafion) contained proteins or carbon chain compounds after 300‐day operation, and however, Nafion 117 seems to be more susceptible to biofouling than the other separators.

Oihane Monzon, Yu Yang, Cong Yu et al.

Environmental Chemistry • 2014

Environmental context The treatment of extremely saline, high-strength wastewaters while producing electricity represents a great opportunity to mitigate environmental effects and recover resources associated with wastes from shale oil and gas production. This paper demonstrates that extreme halophilic microbes can produce electricity at salinity up to 3- to 7-fold higher than sea water. Abstract Many industries generate hypersaline wastewaters with high organic strength, which represent a major challenge for pollution control and resource recovery. This study assesses the potential for microbial fuel cells (MFCs) to treat such wastewaters and generate electricity under extreme salinity. A power density of up to 71mWm–2 (318mWm–3) with a Coulombic efficiency of 42% was obtained with 100gL–1 NaCl, and the capability of MFCs to generate electricity in the presence of up to 250gL–1 NaCl was demonstrated for the first time. Pyrosequencing analysis of the microbial community colonising the anode showed the predominance of a single genus, Halanaerobium (85.7%), which has been found in late flowback fluids and is widely distributed in shale formations and oil reservoirs. Overall, this work encourages further research to assess the feasibility of MFCs to treat hypersaline wastewaters generated by the oil and gas industry.

Aarti Malyan, Geeta Mongia, Shani Kumar

Journal of Applied and Natural Science • 2022

In recent times, the use of energy resources, particularly non-renewable resources, have increased manifolds due to the ever-increasing global demands. This has led to an increase in depletion of the resources and environmental pollution. Microbial Fuel Cells (MFC) are a new concept that has proved to be the solution to the problem as a green energy resource. The paper focuses on generating electricity from wastewater prepared from kitchen wet waste kept for about 168 hours in an attempt to address the energy crisis while also treating it. A comparative analysis of the sample as prepared and with acetate has been studied and power generation, coulombic efficiency and change in chemical oxygen demand (COD) for wastewater were calculated and also the catalytic effect of acetate was analyzed. It was observed that there was a substantial increase in coulombic efficiency and COD content . A coulombic Efficiency efficiency of 25.29% was obtained for the sample with acetate, whereas, without acetate it was calculated as 9.71%. The maximum power density was obtained from the polarization curves. It was observed that the maximum power density of pure kitchen wastewater was found to be 0.017 mW/m2; however, for kitchen wastewater with acetate, the power density increased considerably to 0.546 mW/m2 at an external resistance of 1Kῼ. Further, the maximum current densities observed were 2.239 mA/m2 and 8.771 mA/m2, respectively. The internal resistance of the constructed prototypes was also determined using the maximum power transfer theorem. In this study, a prototype was constructed and it was found that kitchen waste can be used as a source of electricity generation and leads to a green energy initiative.

Yutong Liu, Cong Chen, Xing Xue et al.

Water • 2025

The tobacco production process generates a substantial amount of wastewater characterized by high organics and low biodegradability, which poses a significant risk of severe environmental pollution. In order to explore a clean and low-cost technology for tobacco wastewater treatment, this study constructed two-chamber MFCs and investigated the performance of tobacco wastewater treatment and electricity generation capacity at room temperature. The incorporation of carbon sources (e.g., glucose, acetate, propionate, and butyrate) in wastewater could enhance the removal of COD, total nitrogen and ammonia nitrogen in wastewater. After three cycles, the maximum COD removal rate reached 75.97 ± 1.49%, while the maximum total nitrogen removal and ammonia nitrogen removal rates were 46.95 ± 1.77% and 48.31 ± 1.16%, respectively. Meanwhile, the maximum voltage output of 0.67 V was observed, and the maximum power density was 717.04 mW/m2. The microbial community analysis revealed that Trichococcus and Acinetobacter were present in high abundance in MFCs, which may play a significant role in electricity generation and wastewater treatment. These results demonstrate that MFC is applicable for tobacco wastewater treatment, providing both theoretical foundation and technical references for the large-scale practical application of MFC technology in tobacco wastewater treatment.

Maksudur R Khan, MSA Amin, S Sarker et al.

Journal of Chemical Engineering • 2014

Electricity generation from the biodegradable organic substrate can be accompanied by wastewater treatment, which reduces the cost of industrial effluent treatment. In this study, effluent of local food-processing industries was treated in Membrane-Less Microbial Fuel Cell (ML-MFC) for electricity generation. Several investigations were conducted to enhance the current and voltage generation of MFC in different operating conditions, such as direct industrial effluent, adding drainage sludge concentration, aeration in cathode compartment, increasing the electrode area. In addition, COD removing capability of the ML-MFC was also studied. The study documented a maximum power density of 7.11874mW/m2 with the current density of 97.34mA/m2. COD removal was observed 47% to 74% in all experiments. DOI: http://dx.doi.org/10.3329/jce.v27i2.17803 Journal of Chemical Engineering, IEB Vol. ChE. 27, No. 2, December 2012: 55-59

Jian Hai Li, Yu Bin Fu, Jia Liu et al.

Advanced Materials Research • 2009

As the electrode structure has a great effect on the performance of the benthic microbial fuel cell (BMFC), several graphite electrodes with different shapes (column, plane disk and tubular shape for example) are designed in this paper. The maximum power density (Pm) of BMFC-c and BMFC-d are 20.2 mW•m-2 and 14.9 mW•m-2 respectively, and the internal resistances are 333 Ω and 598 Ω respectively. Three cells are composed of three different sizes of graphite tubes, and their internal diameter of these electrodes are 2.5 cm (called it as BMFC-I for short); 1.0 cm (BMFC-II) and 0 cm (column shape for comparison, BMFC-III) respectively. Test results show that the Pm of BMFC-I, BMFC-II and BMFC-III are 13, 11 and 16 mW•m-2 respectively, and their internal resistances are 435 Ω, 488 Ω and 419 Ω respectively. Results show that the column structure electrode has a lower internal resistance and a higher power density than the disk and tubular structure electrode.

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NeuroQuantology • 2022

Heavy trucks, buses, lorries, and other vehicles require over Rs. 4 lakh crores of diesel each year, which is imported at a cost of approximately Rs. 5 lakh crores annually. These cars' engines use water cooling, which keeps the internal engine components below 100°C.For the following reasons, the material temperature is kept below 100°C. The water in the radiator will boil if the cylinder temperature exceeds 100°C. The liquid lubricant burns and becomes sticky over 140°C, which causes the engine to seize. As a result, the need for a liquid lubricant, the need to cool the radiator and engine cylinders, and the loss of 35 to 40% of the heat equivalent of the diesel can all be avoided. In order to accomplish this, a second stainless steel cylinder is added above the existing conventional engine cylinder. A stainless steel piston then glides inside the stainless steel cylinder, maintaining a very small clearance and requiring no lubrication. A stainless steel piston rod guided by bearings connects the stainless steel piston to the traditional engine piston, and the two pistons reciprocate as a single unit. The traditional cylinder and piston are now just utilized to guide the piston assembly and bearings; the firing has been relocated to a stainless steel cylinder. As a result, the engine's heat flow will be reduced, increasing efficiency. As a result, the radiator is turned off because the traditional cylinder isn't burning, saving 35 to 40 percent of the gasoline that would have been lost to heat dissipation through the radiator. As a result, improving the efficiency of all large trucks could save up to 40 to 50% of the diesel used by large trucks, as well as 1.5 to 2 lakh crores of rupees per year, making this research of national significance

Dileep Ahmad, Muhammad Haroon, Naeemullah et al.

Sustainable Chemical Engineering • 2023

Microbial fuel cell (MFC) is a green technology and is an alternative energy resource of fossil fuels. MFC is the class of Bio-electro-chemical patterns with novel property, like wastewater treatment, electricity generation and biosensor operation. MFCs are ingenious devices that harness the power of bio-electrochemical processes to generate electric current by breaking down organic waste found in wastewater. These systems establish a fascinating connection between microbial metabolism and electricity production. The microbes within the MFCs thrive on the nutrients present in their environment and convert the energy stored in the organic matter into usable electricity. This electrical energy can be effectively utilized to power various essential portable electronic devices such as mobile phones, laptops, TVs, air dryers, threading machines, chargeable torches, as well as devices used in the air force, outer space, and weather stations. The maximum power produced by MFC using an Iron anode is 170 mW·m-2, 0.645 v, while MFCs have better power efficiency in mix culture Microbs 30 mA, 3,600 mW·m-2. It has been observed that MFCs equipped with carbon-based electrodes tend to have a longer lifespan compared to those using metal-based electrodes. However, one drawback of carbon-based electrode MFCs is that they generally exhibit lower power output. In recent times, the investment focus on MFC research has significantly improved the analysis of its chemical, microbiological, and electrochemical aspects. These advancements have led to notable enhancements in the sensing capabilities of MFCs. In this review, we have summarized the MFCs, their working principle, types, composition and the various factors which affect the performance of these MFCs.

Razieh Rafieenia, Mohamed Mahmoud, Fatma El-Gohary et al.

bioRxiv (Cold Spring Harbor Laboratory) • 2022

Abstract Glyphosate, one of the most used herbicides worldwide, is known as an aquatic contaminant of concern, and can present adverse impacts in agroecosystems. In this study, we investigated the degradation of glyphosate in microbial electrochemical systems (MESs), and analysed the microbial composition of enriched anodic biofilms, and comparing them with microbial communities of non-MESs enriched cultures. MESs supported higher glyphosate degradation (68.41 ± 1.21 % to 73.90 ± 0.79 %) compared to non-MESs cultures (48.88 ± 0.51 %). The Linear Sweep Voltammetry (LSV) analysis showed that MESs operated at +300 mV, produced a maximum current of 611.95 μA, which was the highest among all the applied voltages. 16S amplicon sequencing revealed a significant difference in microbial community composition of MESs anodic biofilms and non-MESs enriched communities. The anodic biofilms were dominated by Rhodococcus (51.26 %), Pseudomonas (10.77 %), and Geobacter (8.67 %) while in non-MESs cultures, methanogens including Methanobrevibacter (51.18 %), and Methanobacterium (10.32 %), were the dominant genera. The present study suggested that MESs could be considered as a promising system for glyphosate degradation.

Saba A. Mahdy, Hayder Al-Naseri

Tikrit Journal of Engineering Sciences • 2024

The present study demonstrates the effect of MgO nanoparticles concentrations on industrial wastewater treatment and electricity generation by microbial fuel cells. The MgO nanoparticles were prepared chemically using reflex methods by mixing magnesium hydroxide with ethanol. X-ray diffraction (XRD), Scan Electron Microscopy (SEM), and Fourier Transform Infrared Spectroscopy (FTIR) were done for nanoparticle characterization. (Biological oxygen demand -BOD) and (Chemical oxygen demand - COD) were used as indicators to measure the acidity of wastewater. As a result, microbial fuel cells were proposed as a treatment method for wastewater. Nanoparticles with microbial fuel cell technology will always yield positive results in industrial water treatment. The results showed that using 0.025 mg/ml MgO nanoparticles in microbial fuel cells at pH 3 increased the COD degradation to (95.001%) through 30 min, BOD to (95.05%), and power voltage to (0.76) V. Therefore, treat the wastewater via microbial fuel cells were suggested. Nanoparticles with microbial fuel cell technology will always yield positive results in industrial water treatment.

A.B. Saner, A.K. Mungray

Research Journal of Chemistry and Environment • 2023

Post treatment of Up-flow anaerobic sludge blanket reactor (UASBR) effluents by a duel chambered Microbial fuel cell (MFC) was evaluated for high strength distillery spent wash. Bench scale UASBR (5 L capacity) and MFC (1 L capacity) with carbon electrodes having proton exchange membrane were used to elucidate the energy generation potential and substrate (COD) removal efficiency. Step by step, the influent COD concentration of UASB-MFC unit was increased. The MFC shows increasing trend of open circuit voltage, COD removal and substrate degradation rate with increase in influent COD concentration. The maximum COD removal (73.79%) and open circuit voltage (1.1 V) were achieved at 20600 mg/L of COD. At maximum COD concentration, MFC showed power density (maximum), substrate degradation rate and power yield as 61.61mW/m2, 1.086 kg COD/m3day and 0.041 W/kg CODR respectively. UASB-MFC combined unit gave maximum COD removal of 90%. The experimental data revealed the potential of MFC as feasible, economic (cost saving) and sustainable option.

Enas Taha Sayed, Nobuyoshi Nakagawa

Journal of Chemical Technology & Biotechnology • 2018

Abstract BACKGROUND Yeast, Saccharomyces cerevisiae , is quite safe, easily available, rapid‐growing and one of few microorganisms that can metabolize complex organic materials. The effect of different anode materials such as carbon cloth (CC), carbon paper (CP), Teflon‐treated carbon paper (CP‐T), and porous carbon plate (PCP) on the performance of mediatorless yeast, S. cerevisiae ‐ based MFC was investigated to explore some issues that are affecting the performance. RESULTS The variation in the open circuit voltage (OCV), and power generation for CC, CP and CP‐T, were explained by the different areal densities of the yeast cells that adhered to the anode surface. The highest power was obtained using the CP anode. On the other hand, the PCP anode with dense adhesion of the yeast cells, which was expected to give the highest performance; showed the lowest performance. Modifying the PCP surface with a thin nanolayer of cobalt significantly increased the performance over fifty times. CONCLUSION The performance of a mediatorless yeast‐based microbial fuel cell, i.e. OCV and current density, was affected by the adhesion density of the yeast cell on the electrode surface. However, it was not the only factor affecting the cell performance. The yeast cell adhesion on the anode surface was dependent on the carbon materials. The improvement of the interfacial electron transfer between the anode and yeast cells is key for the development of yeast based mediatorless MFCs. © 2017 Society of Chemical Industry

Hebah Altaweel, Jamal Abu-Ashour, Bassim Abbassi et al.

Research Square • 2025

Abstract Effective management of wastewater treatment plants often require real-time measurements of Biochemical Oxygen Demand (BOD). The conventional methods for determining Biochemical Oxygen Demand (BOD) are often time-consuming, labor-intensive and prone to inaccuracies. Microbial Fuel Cells (MFCs) have emerged as a viable alternative technology for BOD measurement, offering real-time monitoring capability. This study developed a cost-effective dual-chamber MFC with graphite felt electrodes and a CMI-7000 membrane, inoculated with a microbial consortia grown from anaerobic sludge at optimal conditions (35 °C, pH 7, 1000 Ω external resistance). After one month of biofilm formation, the MFC produced 600 mV. Voltage outputs were measured at six BOD 5 concentrations (36 to 583 mg/L) in synthetic wastewater, showing a strong linear correlation between BOD 5 concentrations and voltage outputs. The MFC was also tested with five domestic wastewater samples, and BOD 5 values derived from the voltage-BOD correlation were within 2.5% to 11% of conventional laboratory results. These findings confirm the potential of MFC-based biosensors as an efficient and accurate tool for real-time wastewater monitoring.