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.

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.