Badrus Zaman, Irawan Wisnu Wardhana

E3S Web of Conferences • 2017

Microbial fuel cell is one of attractive electric power generator from nature bacterial activity. While, Evapotranspiration is one of the waste water treatment system which developed to eliminate biological weakness that utilize the natural evaporation process and bacterial activity on plant roots and plant media. This study aims to determine the potential of electrical energy from leachate treatment using evapotranspiration reactor. The study was conducted using local plant, namely Alocasia macrorrhiza and local grass, namely Eleusine Indica . The system was using horizontal MFC by placing the cathodes and anodes at different chamber (i.e. in the leachate reactor and reactor with plant media). Carbon plates was used for chatode-anodes material with size of 40 cm x 10 cm x1 cm. Electrical power production was measure by a digital multimeter for 30 days reactor operation. The result shows electric power production was fluctuated during reactor operation from all reactors. The electric power generated from each reactor was fluctuated, but from the reactor using Alocasia macrorrhiza plant reach to 70 μwatt average. From the reactor using Eleusine Indica grass was reached 60 μwatt average. Electric power production fluctuation is related to the bacterial growth pattern in the soil media and on the plant roots which undergo the adaptation process until the middle of the operational period and then in stable growth condition until the end of the reactor operation. The results indicate that the evapotranspiration reactor using Alocasia macrorrhiza plant was 60-95% higher electric power potential than using Eleusine Indica grass in short-term (30-day) operation. Although, MFC system in evapotranspiration reactor system was one of potential system for renewable electric power generation.

Banu Taşkan

Biomass and Bioenergy • 2020

Roshan Regmi, Rachnarin Nitisoravut

ASEAN Engineering Journal • 2019

Generation of electricity from plant rhizodeposition with an aid of soil bacteria has gained popularity recently as a source of clean and green energy. Power generation from such biosystems is lower than theoretically achieved value due to many constraints. Supplementing the rhizodeposition with external substrates or in situ complementary mechanism can help to enhance the current generation. Therefore, this study aims to improve current from paddy plants with an amendment of Azolla which is hypothesized to augment the bioelectricity production via two mechanisms. These include an addition of organic matters in the system and nitrogen fixation from Azolla which plays a positive role in biomass growth, thereby increasing current. Single chamber sediment PMFCs were built in a facile way, employing commercially available glass chambers with carbon cloth for electrodes, and paddy soil as substrates and inoculum. To have better insight about the system performance, numerous parameters were monitored including daily power output recordings, nature of electric signals, polarization technique, growth nature of the plant, and change in soil physiochemical characteristics. The results revealed that after a week of transplanting of paddy seedlings, the daily current density increased almost twice as compared to the unplanted system. The maximum power in planted reactors was greater by 84% as depicted by power curve. In addition, amended planted reactors with Azolla enhanced the current generation by almost thrice than only planted reactors without amendment, while planted reactors produced current twice than that of from sediments only. Clear circadian oscillation was observed in power output from closed circuit while there is no such demarcation in open circuit voltage during the start-up period.

Riska Anggri Kusuma, Linda Suyati, Wasino Hadi Rahmanto

Jurnal Kimia Sains dan Aplikasi • 2018

The effect of laxose concentration as Lactobacillus bulgaricus bacterial substrate on the cell potential produced in Microbial Fuel Cell System has been done. This study aims to determine the effect of lactose concentration as bacterial substrate, to generate electricity, maximum electric potential and determine the potential value of standard lactose (E ° Lactose.) Based on Nernst equation. The MFC system of two compartments and bridges of salt as a linkage is used in this study. Anode contains lactose with variation of concentration 3 - 7% and bacteria. The cathode contains a 1M KMO4. The electrodes used are graphite. MFC operational time is 14 days. The results showed that the lactose concentration had an effect on the cell potential produced in the MFC system. Maximum cell potential yielded at 4% lactose concentration, that is 710 mV then based on Nerst equation theory obtained E ° Lactose value in MFC system of + 0,236 V.

Unknown Author

Biointerface Research in Applied Chemistry • 2020

This paper summarised different methods used for the electrical power generation using microorganisms in MFC. In the past decade, Microbial Fuel Cells (MFC) attracted many researchers due to their ability to convert organic waste into electric currents by the usage of microorganisms. It has been developing as a great source of renewable energy. This device makes use of simple cathode and anode compartments and a separating membrane. This can be efficiently used for power generations and wastewater treatments. Microbial electrolysis cell (MEC), a type of MFC is also used in generating Hydrogen energy from various biological matters. The performance of MFC totally depends upon the nature of microorganisms, electrodes selected, and the separating membarane used. MFCs serve as a sustainable and alternate energy source to reduce the pollution caused by industrialization. In this review, a detailed explanation about MFC and different ways of generating bioelectricity and hydrogen from wastewater treatment are explained.

Samuel Reinhard Ignatius Sitorus, Mimi Hani Abu Bakar, Edy Herianto Majlan

Jurnal Kejuruteraan • 2020

The world population is projected to increase by one billion for the next ten years from the year 2016. Unfortunately, global power plants still using non-renewable energy sources. Consumption of fossil fuels harms the environment, while nuclear energy could release a significant amount of radioactive material. Besides the energy issues, the growth in population contributes to the high production of wastewater. Every year, the wastewater treatment industry consumes a high input of energy for treatment purposes. These issues invigorate research interest in microbial fuel cell (MFC) technology that can generate green power electricity while breaking down the organic matter in the wastewater. One of the research advancement in MFC is the air-cathode MFC that is scaled-up friendly due to its simple structure, and ability to utilize the abundance of oxygen in the air as the membrane and scaling up arrangements. Therefore, this review aims to discuss the main positive findings contributing to the recent improvement of air-cathode MFC and the obstacles faced for upscaling.

Hung-Yin Tsai, Wei-Hsuan Hsu, Yi-Jhu Liao

Coatings • 2018

Microbial fuel cells (MFCs), which can generate low-pollution power through microbial decomposition, are a potentially vital technology with applications in environmental protection and energy recovery. The electrode materials used in MFCs are crucial determinants of their capacity to generate electricity. In this study, we proposed an electrode surface modification method to enhance the bacterial adhesion and increase the power generation in MFCs. Graphene suspension (GS) is selected as modifying reagent, and thin films of graphene are fabricated on an electrode substrate by spin-coating. Application of this method makes it easy to control the thickness of graphene film. Moreover, the method has the advantage of low cost and large-area fabrication. To understand the practicality of the method, the effects of the number of coating layers and drying temperature of the graphene films on the MFCs’ performance levels are investigated. The results indicate that when the baking temperature is increased from 150 to 325 °C, MFC power generation can increase approximately 4.5 times. Besides, the maximum power density of MFCs equipped with a four-layer graphene anode is approximately four times that of MFCs equipped with a two-layer graphene anode. An increase in baking temperature or number of coating layers of graphene films enhances the performance of MFC power generation. The reason can be attributed to the graphene purity and amount of graphene adhering to the surface of electrode.

Md. T. Noori, D. Paul, M. M. Ghangrekar et al.

Journal of Clean Energy Technologies • 2018

Carlo Santoro, Claudia W. Narvaez Villarubia, Sarah Stariha et al.

ECS Meeting Abstracts • 2014

Due to the high cost of wastewater treatement, new and alternative low cost technologies need to be investigated. Bioelectrochemical systems and particularly microbial fuel cells (MFCs) seem to address positively this problem. In MFCs the organic waste is utilized as a fuel that is oxidised from microorganisms through their metabolism generating electricity. The main problem related with MFCs utilization is the small electricity production and high cost of the electrodes materials. These are the major reasons why MFCs are not commercialized in a large scale yet. In order to overcome the high cost, that is mainly related to the high price of the noble metals used as catalysts at the cathode, inexpensive catalysts for oxygen reduction reaction (ORR) should be explored. These catalysts belong to the group of non platinum based catalyst that are proved as very active towards ORR. This work focused on the utilization of a low cost non-PGM (Fe-Aminoantipyrine) catalyst explored in the design of oxygen reducing cathode for MFCs application. The activity of this catalyst was characterized electrochemically in a three-electrode configuration varying the pH of the electroyte. Then the cathodes were introduced in double chamber MFC (Figure 1) with the cathode completely immersed in the solution. The two compartments (125 ml) of the MFC were separated by proton-exchange membrane (Nafion 211). The anode composed of carbon brush (6x4 cm projected surface area) pre-colonized with mixed cultured bacteria. The anode chamber was filled with 50% in volume PBS (50 mM) and 50% in volume of activated sludge (pH=7.5±0.1). The non-PGM cathode (2.3 x 2.3 cm geometric area) was immersed in solution with different pHs (6, 7.5, 9 and 11) and purged with air for oxygen supply. The MFCs performance was investigated at different pHs in order to simulate possible industrial wastes with pHs different than neutral. The catalyst used in this work was synthesized by modified sacrificial support method which was developed at UNM 1 . In general, the metal precursor (iron nitrate) and nitrogen-containing low-molecular weight organic precursor (4-aminoantipiryne) are deposited on the surface of fumed silica (surface area ~120 m -2 g -1 ). the obtained composite material is heat treated in nitrogen atmosphere at T=950 ° C. After heat treatment fumed silica was removed by excess amount of HF. Potentiodynamic polarizations curve of the anode and the cathode separately were carried out using platinum mesh as a counter and a Ag/AgCl (3M KCl) as reference electrodes with scan rate 0.2 mV/s. MFC overall polarization curves were measured using a potentiostat with a scan rate of 1 mV/s. Power curves were determined using Ohm`s law (P= V x I). The electrochemical measurements of the cathode as a result of differences in the electrolyte pH showed highest electrocatalytic activity of the catalyst at lower pHs. This confirms our previous observation for the dependance of the Fe-AAPyr activity from the electrolyte pH 2 . The polarization and power curves (Figure 2) of the whole MFCs followed the same trend as the cathode polarization curves showing the dominating role of the cathode over the MFCs performance. The MFCs with low pH of the catholyte demonstrated the highest power (200 μW) and the highest open circuit voltage (OCV = 850 mV). This study demonstrated the applicability of non-PGM catalyst for the development of cathodes for MFC application. Further studies with improved MFCs design should be performed. Long-term operation test will be carried out investigating the influence of the wastewater pollutants on the cathode and subsequently the whole MFC operation and output. References A. Serov, U. Martinez, A. Falase, P. Atanassov, Electrochem. Comm. 22 (2012) 193-196. S. Brocato, A. Serov, P. Atanassov Electrochim. Acta, 87 (2013) 361-365

Farid Salahudin, M. Rusdi Hidayat

JURNAL BORNEO AKCAYA • 2014

Microbial Fuel Cell is the one of renewable technology which can produseed electric energy from waste and other organic matter. MFC reactor have two part wich called anode and cattode chamber that bonded with cattion exchange membrane. Electric energy in MFC was produced by biochemistry reaction in organic matter like palm industrial waste. One of organic matter that pontential in Indonesia is palm industry waste. The aim in this research is to know the potential electric energy in MFC reactor with palm industry waste. The conclusion in this research is MFC with palm industry waste can produced electric energy higher than MFC with 0,5 M glucose solution. 

Muralidharan Ayyappan, Dimpal Parida, Arti Yadav et al.

Nature Precedings • 2011

Abstract Microbial production of electricity is an important form of bioenergy since Microbial Fuel cells (MFC) offer the possibility of extracting electric current from a wide range of organic wastes and renewable biomass. Factors affecting the MFC operational effectiveness are the MFC design and the bacterial metabolism and electron transfer. The purpose of this study is to identify species which are responsible for electricity generation so as to build a suitable consortium and to investigate the relative efficiencies between the microbial consortiums. Enrichment by repeated transfer of a bacterial consortium harvested from the anode compartment of a MFC with synthetic media as a substrate increased the output from an initial level of 34 mA to a maximal level of 363 mA. Scanning electron microscope image indicated the enhanced microbial biofilm deposition over the electrode which were not initially detected in the community.

Tingting Yu, Lifen Liu, Qiao Yang et al.

RSC Advances • 2014

Cathode membrane, made of PANI modified polyester cloth, was coated with a new and high-efficiency carbon foam–Fe–Co catalyst, which is filterable, conductive and catalytic. The power density increased 38 times.

Jung Mi Moon, Sanath Kondaveeti, Tae Ho Lee et al.

Bioelectrochemistry • 2015

Kenneth Erich Richter, Robert George

ECS Meeting Abstracts • 2014

Microbial fuel cells (MFCs) work by providing bacteria in anaerobic sediments with an electron acceptor (anode) that stimulates metabolism of organic matter. The buried anode is connected via control circuitry to a cathode exposed to oxygen in the overlying water. During metabolism, bacteria release hydrogen ions into the sediment and transfer electrons extra-cellularly to the anode, which eventually reduce dissolved oxygen at the cathode, forming water. The open circuit voltage is approximately 0.8 v. The voltage between electrodes is operationally kept at 0.4 v with a potentiastat. The current is chiefly limited by the rate of microbial metabolism at the anode. The Office of Naval Research has encouraged development of microbial fuel cells in the marine environment at a number of academic and naval institutions. Work at SPAWAR, a navy laboratory in San Diego, involves fuel cell design and testing, applications to low power Navy sensors, and studies of important environmental parameters that affect fuel cell performance. Earlier work in shallow sediments of San Diego Bay showed that the most important environmental parameters that control fuel cell power output in San Diego Bay were total organic carbon in the sediment and seasonal water temperature. Parameters that we dismissed as unimportant were dissolved oxygen levels, light level, and initial sediment bacterial populations. Parameters whose affect we could not separate were total organic carbon and grain size. Current MFC work at SPAWAR includes extension of microbial fuel cell tests to the deep sea environment (>1000 m) and, in parallel, testing microbial fuel cells in the laboratory under deep sea conditions. One question we are asking is whether MFC power output from deep water sediments repressurized and chilled in the laboratory comparable to those measured in situ. If yes, mapping the power potential of deep sea sediments may be made much easier, requiring sediment grabs and lab tests rather than deployment and retrieval of fuel cells. Another question we are asking is whether in situ temperature and total organic carbon in the deep sea sediment can predict MFC power. If yes, then we can make use of the large collection of publicly available, deep sea oceanographic measurements to make these predictions, foregoing expensive work at sea. These regressions will be compared to those derived from shallow water measurements. In order to meet these goals we are pursuing a field effort to (1) deploy a microbial fuel cell in progressively deeper water, (2) record in situ power and temperature over several weeks, and (3) retrieve the fuel cell along with sediment samples for analysis. We are also pursuing a laboratory effort to (1) build a matching microbial fuel cell in a pressure vessel capable of matching the pressure and temperature of deep water, (2) capable of flushing the fuel cell with oxygenated water under pressure to allow equilibrium power production, and (3) stock the pressure vessel with deep water sediment in order to take measurements analogous to those in the field. The current progress and results from this work at SPAWAR will be presented.

Lu Lu, Cuiping Zeng, Luda Wang et al.

Scientific Reports • 2015

Abstract Graphene oxide (GO) is an emerging material for energy and environmental applications, but it has been primarily produced using chemical processes involving high energy consumption and hazardous chemicals. In this study, we reported a new bioelectrochemical method to produce GO from graphite under ambient conditions without chemical amendments, value-added organic compounds and high rate H 2 were also produced. Compared with abiotic electrochemical electrolysis control, the microbial assisted graphite oxidation produced high rate of graphite oxide and graphene oxide (BEGO) sheets, CO 2 and current at lower applied voltage. The resultant electrons are transferred to a biocathode, where H 2 and organic compounds are produced by microbial reduction of protons and CO 2, respectively, a process known as microbial electrosynthesis (MES). Pseudomonas is the dominant population on the anode, while abundant anaerobic solvent-producing bacteria Clostridium carboxidivorans is likely responsible for electrosynthesis on the cathode. Oxygen production through water electrolysis was not detected on the anode due to the presence of facultative and aerobic bacteria as O 2 sinkers. This new method provides a sustainable route for producing graphene materials and renewable H 2 at low cost and it may stimulate a new area of research in MES.

Yaping Zhang, Jian Sun, Bin Hou et al.

Journal of Power Sources • 2011

Ayan Bandyopadhyay, Ibtisam Khalaf

Journal of Emerging Investigators • 2014

Microbial fuel cells produce electricity while breaking down organic waste. However, they have low power output because of the poor kinetics of oxygen reduction at the cathode under neutral pH conditions. In this project, we developed a novel microbial fuel cell with a biocathode using cobalt oxidation and reduction, to determine whether a cobalt biocathode could increase power density more than the conventional manganese biocathode. We built three types of fuel cells; the control had only oxygen reduction in the cathode chamber. The second and third cells included manganese and cobalt, respectively, with oxygen reduction. Shewanella oneidensis was used to oxidize organic material at the anode chamber and Leptothrix cholodnii was used in the biocathode. We measured power output when the fuel cells had reached peak voltage under a limited glucose supply. We found that the cobalt biocathode resulted in a higher power density than the control group and the manganese biocathode, but took the longest to reach peak voltage, indicating that microbial biofilm formation takes longer when oxidizing cobalt than it does when oxidizing manganese.

Hyung-Sool Lee, César I. Torres, Prathap Parameswaran et al.

Environmental Science & Technology • 2009

Douglas F. Call, Rachel C. Wagner, Bruce E. Logan

Applied and Environmental Microbiology • 2009

ABSTRACT A hydrogen utilizing exoelectrogenic bacterium ( Geobacter sulfurreducens ) was compared to both a nonhydrogen oxidizer ( Geobacter metallireducens ) and a mixed consortium in order to compare the hydrogen production rates and hydrogen recoveries of pure and mixed cultures in microbial electrolysis cells (MECs). At an applied voltage of 0.7 V, both G. sulfurreducens and the mixed culture generated similar current densities (ca. 160 A/m 3 ), resulting in hydrogen production rates of ca. 1.9 m 3 H 2 /m 3 /day, whereas G. metallireducens exhibited lower current densities and production rates of 110 ± 7 A/m 3 and 1.3 ± 0.1 m 3 H 2 /m 3 /day, respectively. Before methane was detected in the mixed-culture MEC, the mixed consortium achieved the highest overall energy recovery (relative to both electricity and substrate energy inputs) of 82% ± 8% compared to G. sulfurreducens (77% ± 2%) and G. metallireducens (78% ± 5%), due to the higher coulombic efficiency of the mixed consortium. At an applied voltage of 0.4 V, methane production increased in the mixed-culture MEC and, as a result, the hydrogen recovery decreased and the overall energy recovery dropped to 38% ± 16% compared to 80% ± 5% for G. sulfurreducens and 76% ± 0% for G. metallireducens . Internal hydrogen recycling was confirmed since the mixed culture generated a stable current density of 31 ± 0 A/m 3 when fed hydrogen gas, whereas G. sulfurreducens exhibited a steady decrease in current production. Community analysis suggested that G. sulfurreducens was predominant in the mixed-culture MEC (72% of clones) despite its relative absence in the mixed-culture inoculum obtained from a microbial fuel cell reactor (2% of clones). These results demonstrate that Geobacter species are capable of obtaining similar hydrogen production rates and energy recoveries as mixed cultures in an MEC and that high coulombic efficiencies in mixed culture MECs can be attributed in part to the recycling of hydrogen into current.

Yejie Ye, Liyong Wang, Yingwen Chen et al.

Water Science and Technology • 2010

The single-chamber membrane-less MEC exerted much better hydrogen production performance while given higher applied voltages than it did at lower. High applied voltages that could shorten the reaction time and the exposure of anode to air for at least 30 min between cycles can significantly suppress methanogen and increase hydrogen production. At an applied voltage of 1.0 V, a hydrogen production rate of 1.02 m3/m3/day with a current density of 5.7 A/m2 was achieved. Cathodic hydrogen recovery and coulombic efficiency were 63.4% and 69.3% respectively. The hydrogen concentration of mixture gas produced of 98.4% was obtained at 1.0 V, which was the best result of reports. The reasons that such a high hydrogen concentration can be achieved were probably the high electrochemical activity and hydrogen production capability of the active microorganisms. Increase in substrate concentrations could not improve MEC's performance, but increased the reaction times. Further, reactor configuration and operation factors optimisation should be considered to increase current density, hydrogen production rate and hydrogen recovery.

Miriam Rosenbaum, Michael A. Cotta, Largus T. Angenent

Biotechnology and Bioengineering • 2010

Abstract We studied the effects of aeration of Shewanella oneidensis on potentiostatic current production, hydrogen production in a microbial electrolysis cell, and electric power generation in a microbial fuel cell (MFC). The potentiostatic performance of aerated S. oneidensis was considerably enhanced to a maximum current density of 0.45 A/m 2 or 80.3 A/m 3 (mean: 0.34 A/m 2 , 57.2 A/m 3 ) compared to anaerobically grown cultures. Biocatalyzed hydrogen production rates with aerated S. oneidensis were studied within the applied potential range of 0.3–0.9 V and were highest at 0.9 V with 0.3 m 3 H 2 /m 3 day, which has been reported for mixed cultures, but is ∼10 times higher than reported for an anaerobic culture of S. oneidensis . Aerated MFC experiments produced a maximum power density of 3.56 W/m 3 at a 200‐Ω external resistor. The main reasons for enhanced electrochemical performance are higher levels of active biomass and more efficient substrate utilization under aerobic conditions. Coulombic efficiencies, however, were greatly reduced due to losses of reducing equivalents to aerobic respiration in the anode chamber. The next challenge will be to optimize the aeration rate of the bacterial culture to balance between maximization of bacterial activation and minimization of aerobic respiration in the culture. Biotechnol. Bioeng. 2010;105: 880–888. © 2009 Wiley Periodicals, Inc.

Falk Harnisch, Uwe Schröder

ChemSusChem • 2009

Abstract During the operation of a microbial bioelectrochemical system, charge balance must be maintained between the anode and the cathode. In an ideal scenario, the charge balance would be realized by the unhindered migration of H + or OH − . At the same time, any kind of diffusion (crossover) between both electrode compartments should be avoided. However, as several studies have demonstrated, the experimental reality does not match this ideal picture. Crossover processes occur and H + /OH − migration only plays an inferior role in the charge‐balancing ion transfer, which results in significant losses in the performance of the microbial bioelectrochemical system. This Minireview summarizes the conflict of selectivity versus mobility and discusses principle strategies to cope with the resulting constraints, including pH‐static operation and the use of different separator materials and membrane‐free systems. Finally, we show that every setup compromises either selectivity or mobility, and no apparent ideal solution currently exists.

K. Rabaey, J. Keller

Water Science and Technology • 2008

Microbial fuel cells that can generate energy out of wastewaters are close to pilot scale testing. As such, MFC technology is complementary to methane generation due to the possibility to rapidly convert organic acids, polish effluents and work at low substrate concentrations. The main bottleneck perceived at the moment is the cathodic electron transfer. A variety of catalysts has been investigated for the direct transfer of electrons from the cathode to oxygen in the air. Overlooked in this context were bacteria. Bacteria could indeed be worthwhile to replace chemical catalysts. Moreover, their versatility enables us to not only target at oxygen, but also at nitrous oxides and contaminants as possible drivers of electricity generation, nutrient removal and bioremediation. This paper addresses several recent developments in MFC cathode research, and demonstrates that energy generation is but an aspect of this versatile technology.

Giulio Zanaroli, Sara Di Toro, Daniela Todaro et al.

Microbial Cell Factories • 2010

Abstract Background The bioremediation of soils impacted by diesel fuels is very often limited by the lack of indigenous microflora with the required broad substrate specificity. In such cases, the soil inoculation with cultures with the desired catabolic capabilities (bioaugmentation) is an essential option. The use of consortia of microorganisms obtained from rich sources of microbes (e.g., sludges, composts, manure) via enrichment (i.e., serial growth transfers) on the polluting hydrocarbons would provide bioremediation enhancements more robust and reproducible than those achieved with specialized pure cultures or tailored combinations (co-cultures) of them, together with none or minor risks of soil loading with unrelated or pathogenic allocthonous microorganisms. Results In this work, two microbial consortia, i.e., ENZ-G1 and ENZ-G2, were enriched from ENZYVEBA (a complex commercial source of microorganisms) on Diesel (G1) and HiQ Diesel (G2), respectively, and characterized in terms of microbial composition and hydrocarbon biodegradation capability and specificity. ENZ-G1 and ENZ-G2 exhibited a comparable and remarkable biodegradation capability and specificity towards n-C10 to n-C24 linear paraffins by removing about 90% of 1 g l -1 of diesel fuel applied after 10 days of aerobic shaken flask batch culture incubation at 30°C. Cultivation dependent and independent approaches evidenced that both consortia consist of bacteria belonging to the genera Chryseobacterium , Acinetobacter , Psudomonas , Stenotrophomonas , Alcaligenes and Gordonia along with the fungus Trametes gibbosa . However, only the fungus was found to grow and remarkably biodegrade G1 and G2 hydrocarbons under the same conditions. The biodegradation activity and specificity and the microbial composition of ENZ-G1 and ENZ-G2 did not significantly change after cryopreservation and storage at -20°C for several months. Conclusions ENZ-G1 and ENZ-G2 are very similar highly enriched consortia of bacteria and a fungus capable of extensively degrading a broad range of the hydrocarbons mainly composing diesel fuels. Given their remarkable biodegradation potential, stability and resistance to cryopreservation, both consortia appear very interesting candidates for bioaugmentation operations on Diesel fuel impacted soils and sites.

Jian Sun, Yongyou Hu, Zhe Bi et al.

Journal of Power Sources • 2009

Wei Ping Liu, Xia Fei Yin

Advanced Materials Research • 2013

A continuous flow double chamber microbial fuel cell (MFC) for wastewater treatment was constructed. Anaerobic activated sludge was used as bacterial source and simulated organic wastewater was used as substrate. Effluent of anode chamber was used directly as influent of the cathode chamber. The aerobic microorganisms could degrade organic matters further. The electricity production and organic wastewater treatment of the MFC were studied. The results show that the wastewater chemical oxygen demand (COD) of the total removal rate was 74.1%~77.45%, the anode chamber in which the removal rate of COD is 32.2%~35.3%, and COD removal efficiency of aerobic biological treatment in the cathode chamber was 60.2%~66.7%. The continuous flow system could improve the removal rate further. The maximum current density of MFC was 1.56 mAm-2, the maximum output power was 24.336 mWm-2.

D. Ki, J. Park, J. Lee et al.

Water Science and Technology • 2008

In this study, we performed microbial community analysis to examine microbial diversity and community structure in microbial fuel cells (MFCs) seeded with activated sludge from a municipal wastewater treatment plant in South Korea. Because anode-attached biofilm populations are particularly important in electricity transfer, the ecological characteristics of anode-attached biofilm microbes were explored and compared with those of microbes grown in suspension in an anode chamber. 16S rDNA-based community analysis showed that the degree of diversity in anode-attached biofilms was greater than that of the originally seeded activated sludge as well as that of the suspension-grown microbes in the anode bottle. In addition, Bacteroidetes and Clostridia grew preferentially during MFC electricity generation. Further phylogenetic analysis revealed that the anode biofilm populations described in this work are phylogenetically distant from previously characterized MFC anode biofilm microbes. These findings suggest that a phylogenetically diverse set of microbes can be involved in the electricity generation of MFC anode compartments, and that increased microbial diversity in anode biofilms may help to stabilize electricity production in the MFC.

Guang Zhao, Li Wei, Fang Ma et al.

Advanced Materials Research • 2010

The microbial fuel cell (MFC) constructed by a modified Continuous Stirred Tank Reactor (CSTR) which was used as acidification-phase of two-phase anaerobic digestion system. The experiment was operated as batch mode at mesophilic condition (35°C) to evaluate continue voltage output using cattle dung as substrate in hydrolysis-acidification process. The results illustrated that electricity generation increased noticeably to 300mV after 3 days operation, reached 430mV after 20 days and stabilized electricity generation from 420mV to 470mV in the following 70 days. The pH decreased from 7.15 to 6.65 after 15 days operation and maintained stability from 6.4 to 6.8. The main components of VFA in anode chamber were acetic, propionic and butiric acids. The dominating VFA was acetic acid that predominated untile day 50 and the maximum propionic acid concentration was 15% of total VFA.

M. M. Ghangrekar, V. B. Shinde

Water Science and Technology • 2008

Long term performance of mediator-less and membrane-less microbial fuel cell (ML-MFC) was evaluated for treatment of synthetic and actual sewage and electricity harvesting. The anode chamber of ML-MFC was inoculated with pre-heated mixed anaerobic sludge collected from a septic tank. The ML-MFC was operated by feeding synthetic wastewater for first 244 days, under different organic loading rates, and later with actual sewage for next 30 days. Maximum chemical oxygen demand (COD) removal efficiency of 91.4% and 82.7% was achieved while treating synthetic wastewater and actual sewage, respectively. Maximum current of 0.33 mA and 0.17 mA was produced during synthetic and actual sewage treatment, respectively. Maximum power density of 6.73 mW/m2 (13.65 mW/m3) and maximum current density of 70.74 mA/m2 was obtained in this membrane-less MFC with successful organic matter removal from wastewater.

Cody S. Madsen, Michaela A. TerAvest

Scientific Reports • 2019

AbstractShewanella oneidensis MR-1 is quickly becoming a synthetic biology workhorse for bioelectrochemical technologies due to a high level of understanding of its interaction with electrodes. Transmembrane electron transfer via the Mtr pathway has been well characterized, however, the role of NADH dehydrogenases in feeding electrons to Mtr has been only minimally studied in S. oneidensis MR-1. Four NADH dehydrogenases are encoded in the genome, suggesting significant metabolic flexibility in oxidizing NADH under a variety of conditions. A strain lacking the two dehydrogenases essential for aerobic growth exhibited a severe growth defect with an anode (+0.4 VSHE) or Fe(III)-NTA as the terminal electron acceptor. Our study reveals that the same NADH dehydrogenase complexes are utilized under oxic conditions or with a high potential anode. Our study also supports the previously indicated importance of pyruvate dehydrogenase activity in producing NADH during anerobic lactate metabolism. Understanding the role of NADH in extracellular electron transfer may help improve biosensors and give insight into other applications for bioelectrochemical systems.

Jonathon Ryan, Hayden Ferral-Smith, Joshua Wilson

PAM Review Energy Science & Technology • 2018

Microbial Fuel Cells (MFCs) are an area of increasing research for use as an alternative energy source, due to their ability to produce electricity while simultaneously treating organic waste. This meta-study determines the optimal MFC configuration for electricity production, through consideration of the biocatalyst and substrate used. This study focuses primarily on comparing the use of mixed microbial consortia to pure strains of biocatalyst, and the use of waste water in contrast to simple substrates such as; acetate, glucose, and lactate. The use of algae as a substrate, and as a biocatalyst, is also investigated. In this study, only single and dual chamber MFCs are compared, and power density standardised to anode surface area (mW/m2) is used as a metric to facilitate the comparison of different experimental setups. This meta-study shows that dual chamber MFCs, using simple substrates, when catalysed by mixed culture biocatalysts, produce greater power densities, than algae, and complex substrates, with average power densities of 280, 70 and 30 (mW/m2) observed respectively. In single chamber MFC configurations, mixed culture biocatalysts have been observed to yield approximately double the power output of pure culture biocatalysts.

Jin-Zhi Sun, Quan-Cheng Shu, Hong-Wei Sun et al.

Molecules • 2024

Microbial fuel cells (MFCs) have the potential to directly convert the chemical energy in organic matter into electrical energy, making them a promising technology for achieving sustainable energy production alongside wastewater treatment. However, the low extracellular electron transfer (EET) rates and limited bacteria loading capacity of MFCs anode materials present challenges in achieving high power output. In this study, three-dimensionally heteroatom-doped carbonized grape (CG) monoliths with a macroporous structure were successfully fabricated using a facile and low-cost route and employed as independent anodes in MFCs for treating brewery wastewater. The CG obtained at 900 °C (CG-900) exhibited excellent biocompatibility. When integrated into MFCs, these units initiated electricity generation a mere 1.8 days after inoculation and swiftly reached a peak output voltage of 658 mV, demonstrating an exceptional areal power density of 3.71 W m−2. The porous structure of the CG-900 anode facilitated efficient ion transport and microbial community succession, ensuring sustained operational excellence. Remarkably, even when nutrition was interrupted for 30 days, the voltage swiftly returned to its original level. Moreover, the CG-900 anode exhibited a superior capacity for accommodating electricigens, boasting a notably higher abundance of Geobacter spp. (87.1%) compared to carbon cloth (CC, 63.0%). Most notably, when treating brewery wastewater, the CG-900 anode achieved a maximum power density of 3.52 W m−2, accompanied by remarkable treatment efficiency, with a COD removal rate of 85.5%. This study provides a facile and low-cost synthesis technique for fabricating high-performance MFC anodes for use in microbial energy harvesting.

Mulu Berhe Desta, Dagmawi Girmay Tebeje, Hagos Mebrahtu Gebrehiwot

Journal of Energy Research and Reviews • 2023

MFCs are bio-electrochemical devices that are capable of transforming chemical energy stored in waste organic matter into direct electrical energy through catalytic activity of microorganisms under anaerobic conditions. Bio-electrochemical systems, such as microbial fuel cells (MFCs), serve as greener alternatives to conventional fuel energy. In recent years, MFCs have drawn science community interest as a method for direct bioelectricity recovery from wastewater while simultaneously treating the wastewater. Moreover; they gain a competitive advantage over other water treatment technologies due to their unique features such as huge energy benefits, less environmental impact, good operating stability, and high economic efficiency. Reports reveal that MFCs are the subject of much interest to researchers, and the number of papers on MFCs in wastewater treatment is increasing. The ever-growing demand for green waste management and renewable sources of energy has enthused research efforts all over the world. This study, therefore, investigated the effect of process variables on the bio-electrical performance of H-type microbial fuel cells fueled with brewery wastewater and inoculated with distillery plant waste. From the experimental results, 1150mV maximum voltage output, 92.85%, 91.40%, 68.87%, and 70.10% removal efficiencies of COD, BOD, TN and TP respectively were obtained at 35ºC, pH 7, and 5 days. These results confirmed that brewery wastewater effectively treated would generate a considerable amount of direct bio-electricity. Results also revealed that the MFC provides an alternative insight into an effective treatment of wastewater that can simultaneously generate a direct bio-electricity in a sustainable and eco-friendly manner.

Arjun Ajith Mohan, Sandhyarani N

ECS Meeting Abstracts • 2019

Para amino benzoic acid is used in the synthesis of folic acid by bacteria. It is biologically important for the survival of bacteria in the human intestinal tract. This biological and physiologically important molecule can be used to achieve immobilization of glucose oxidase on nanomaterial modified electrodes. This work focuses on the grafting of pABA on graphene oxide modified carbon fabric electrode. The immobilized enzymes have been used to generate electrons from glucose through direct electron transfer at a potential of -490 mV. Electrochemically deposited reduced graphene oxide was used as the cathode with an oxygen reduction potential of -200mV. The anode and the cathode were inserted into a 3D printed electrode holder with an inter electrode distance of 50mm and an OCV of 107mV was obtained. The compact design of the fuel cell combined with it’ s eco-friendly nature makes this an ideal construction for use as a biolfuel cell.

Laura Malavola, Silvia Franz, Massimiliano Bestetti et al.

E3S Web of Conferences • 2022

This work investigates Reduced Titanium Oxide (RTO) in comparison with Carbon Cloth (CC) and commercial Boron Doped Diamond (BDD) as anodes in hyperthermophilic bioelectrochemical systems operating at 80°C by Thermotoga neapolitana. Two samples of RTO were synthesized by plasma electrolytic oxidation (PEO) of titanium plates and subsequent electrochemical reduction. Electrochemical performance of CC, BDD, and RTO are tested by performing cyclic voltammetry in the anodic region (0-1V, 50 mV/s), in abiotic and biotic conditions. The surface of colonized materials is observed by SEM microscopy. Results show that bacteria fast settle on all tested material, significantly affecting their electrochemical conductivity. The integration of voltammetric cycles reveals that biofilm generates capacitive effects on the anodic surfaces, particularly evident in RTO, less in CC and absent in BDD. Charge densities provided by capacitive response of RTO and CC are of the order of 5.58 and 0.77 mC/cm2, respectively.

Fátima Borja-Maldonado, Miguel Ángel López Zavala

Bioengineering • 2023

In this study, graphite, graphene, and hydrophilic-treated graphene electrodes were evaluated in a dual-chamber microbial fuel cell (DC-MFC). Free-oxygen conditions were promoted in anodic and cathodic chambers. Hydrochloric acid at 0.1 M and pH 1.1 was used as a catholyte, in addition to deionized water in the cathodic chamber. Domestic wastewater was used as a substrate, and a DuPontTM Nafion 117 membrane was used as a proton exchange membrane. The maximum power density of 32.07 mW·m−2 was obtained using hydrophilic-treated graphene electrodes and hydrochloric acid as catholyte. This power density was 1.4-fold and 32-fold greater than that of graphene (22.15 mW·m−2) and graphite (1.02 mW·m−2), respectively, under the same operational conditions. In addition, the maximum organic matter removal efficiencies of 69.8% and 75.5% were obtained using hydrophilic-treated graphene electrodes, for hydrochloric acid catholyte and deionized water, respectively. Therefore, the results suggest that the use of hydrophilic-treated graphene functioning as electrodes in DC-MFCs, and hydrochloric acid as a catholyte, favored power density when domestic wastewater is degraded. This opens up new possibilities for improving DC-MFC performance through the selection of suitable new electrode materials and catholytes.

Frédéric Barrière, Thomas Flinois

ECS Meeting Abstracts • 2020

Oxygen biocathodes with electroactive biofilms on graphite electrodes were developed consistently and reproducibly from wastewater inoculum under a high ammonium content selective pressure in a batch microbial fuel cell configuration using ferrocyanide at the anode. The microbial biocathodes process nitrification reactions and catalyse the reduction of molecular oxygen with an onset potential of 0.0 V vs. Ag /AgCl, and a current density at -0.28 V of j = -296 μA/cm2 at pH 7 and 20 °C under oxygen saturation (Cf. Figure).These biofilms also reduce hydrogen peroxide (not shown) at +0.25 V, the potential of an electroactive species in the biofilm (Cf. Figure). The nitrification reactions performed by the biofilm are found to be associated with the catalytic reduction of dioxygen. Nitrification reactions were studied by assaying the nitrogen species (ammonium, nitrite and nitrate) and the effect of adding hydroxylamine, an intermediate of the enzymatic oxidation of ammonium. Metagenomic studies via 16S rRNA gene sequencing of the biofilms onto the colonized electrodes were performed 4 week after inoculation. These studies show that the cathodic biofilms were significantly enriched with Cupriavidus, a proteobacteria genus, that is likely to be responsible for the catalytic properties of the microbial biocathode. The Figure shows the reduction of molecular oxygen by a colonized electrode at pH 7 and 20 °C in a 0.1 M fresh phosphate buffer as recorded with slow scan rate cyclic voltammetry. Scan rate: 1 mV/s. Green: abiotic graphite electrode under oxygen saturation. Black: biocathode under argon saturation. Red: biocathode under air. Blue: biocathode under oxygen saturation. Note also the chemically reversible system found at +0.25 V and assigned to the biofilm. Catalytic hydrogen peroxide reduction (not shown) occurs at the potential of this system. Figure 1

Alfiah Alif, Muhamad Jalil Baari, Amalyah Febryanti

KOVALEN: Jurnal Riset Kimia • 2022

Microbial fuel cell (MFC) is a technology that utilizes bacteria in organic medium that can convert chemical energy into electrical energy. This technology can be used to treat fishery waste and shrimp waste which is rich in organic matter. This study aimed to measure the performance of the MFC system on fishery wastewater and shrimp wastewater as a means of producing bio-electricity while reducing the waste load. This study used different types of electrodes, including zinc, aluminum, copper, and carbon graphite. This technology used 0.2 M KMNO4 electrolyte solution. The research method includes three stages; production of fishery wastewater and shrimp wastewater, assembly of a dual chamber MFC bioreactor, and measurement of waste electrical energy produced. The value of electricity production with the highest average in fishery wastewater was obtained by adding electrolyte solution to the Zn/Cu electrode during 117 hours of observation were 6.86 mA with a potential difference of 1.469 V meanwhile in shrimp wastewater was obtained by adding electrolyte solution to the Al/Cu electrode were 4.38 mA with a potential difference of 1.335 V.This study can be concluded that higher electricity production is obtained from the utilization of fish wastewater using Zn/Cu electrode.

Amandeep Singh, Balaji Krishnamurthy

Journal of Electrochemical Science and Engineering • 2019

Microbial fuel cells use bacteria to generate electrical energy and are used for lower power density applications. This paper studies the effect of operational parameters on the performance of a microbial fuel cell. The effect of length of the anode compartment, inlet acetate concentration, acetate flow rate, temperature, thickness of the membrane and bio-film conductivity on the performance of the fuel cell is modeled. The thickness of the membrane is found to play a very limiting role in affecting the performance of the fuel cell. However, the length of the anode compartment, acetate flow rate and bio-film conductivity are found to play a significant role in the performance of the fuel cell. Model results are compared with experimental data and found to compare well.

Geetanjali, R. Rani, S. Kumar

Fuel Cells • 2019

AbstractMicrobial fuel cell (MFC) technology has potential to generate bioelectricity. However, the low power density problem is considerably associated with anode materials and its performance. In this study, modified anodes for single chamber MFC (SMFC) have been developed using NiWO4 impregnated on reduced graphene oxide (rGO) (NWG) composite. The analytical and morphological properties of rGO, NiWO4 particles and NWG composites have been characterized by FTIR, XRD, SEM and TEM. The electrochemical activity and capacitance of modified anode(s) are determined by cyclic voltammetry and galvanostatics charge‐discharge, respectively. Modified NWG composite (2 mmol)‐carbon cloth (CC) anode has highest capacitance value of 47.27 ± 0.18 F cm−2. The maximum power density obtained by modified NWG composite (2 mmol)‐CC anode was observed to be 1128 ± 42 mW m−2 which was 6.57 times higher than the unmodified anode (171 ± 8 mW m−2). Electrochemical impedance spectra results indicate a substantial improvement in electron transfer between the microbes and the modified NWG composites‐CC anodes. The decrease in the internal resistance of SMFC system is observed due to the improved electrochemical capacitance and synergistic effect between NiWO4 and rGO. In conclusion, modified NWG composites‐CC anodes enhance the performance considerably and show excellent potential in electrode surface electrocatalyst modifier in MFCs.