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A single-chamber microbial fuel cell (MFC) was used in this study to treat recycled stillage obtained from food waste ethanol fermentation. Corresponding substrates inside the system were evaluated by fluorescence spectra, and microbial communities were also investigated. Results demonstrated that output voltage and current, respectively, reached 0...
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... This effect is compounded by the internal resistance within MFCs, which comprises three main components: ohmic resistance, resistance to electrochemical reaction and resistance to mass transfer [49][50][51]. The study by Ma et al. (2018) provides insightful observations on the variability of microbial communities within MFCs, especially when processing certain organic wastes like food scraps. The researchers discovered that, while the same microbial species were present in both anodic and cathodic biofilms, their proportions varied significantly. ...
... The researchers discovered that, while the same microbial species were present in both anodic and cathodic biofilms, their proportions varied significantly. Specifically, they identified Proteobacteria (61% at the anode, 42.9% at the cathode), Bacteroidetes (22.9% at the anode, 34.5% at the cathode) and Firmicutes (9% at the anode, 7.5% at the cathode), collectively constituting over 80% of the total bacterial population in these environments [52]. A crucial aspect of electrical energy generation in MFCs is the electron generation mechanism, whether through direct or indirect transfer, where microbial metabolism plays a vital role. ...
Agroindustry waste has exponentially increased in recent years, generating economic losses and environmental problems. In addition, new ways to generate sustainable alternative electrical energy are currently being sought to satisfy energy demand. This investigation proposes using avocado waste as fuel for electricity generation in single-chamber MFCs. The avocado waste initially operated with an ambient temperature (22.4 ± 0.01 °C), DO of 2.54 ± 0.01 mg/L, TDS of 1358 ± 1 mg/L and COD of 1487.25 ± 0.01 mg/L. This research managed to generate its maximum voltage (0.861 ± 0.241 V) and current (3.781 ± 0.667 mA) on the fourteenth day, operating at an optimal pH of 7.386 ± 0.147, all with 126.032 ± 8.888 mS/cm of electrical conductivity in the substrate. An internal resistance of 67.683 ± 2.456 Ω was found on day 14 with a PD of 365.16 ± 9.88 mW/cm2 for a CD of 5.744 A/cm2. Micrographs show the formation of porous biofilms on both the anodic and cathodic electrodes. This study gives preliminary results of using avocado waste as fuel, which can provide outstanding solutions to agro-industrial companies dedicated to selling this fruit.
... Due to the biological factors that can affect the overall performance of MFCs, including bioelectricity generation and operational cost, the substrate has received considerable attention (Ullah & Zeshan 2020). Numerous studies have examined the utilization of organic compounds derived from food and plant waste (Hongzhi et al. 2018;Qingliang et al. 2017). The majority of studies have concentrated on liquid solid waste as opposed to solid waste. ...
This paper describes a device known as a Single-chamber Microbial Fuel Cell (SMFC) that was used to generate bioelectricity from plant waste containing lignocellulosic components, such as bamboo leaves, rice husk and coconut waste, with various anodic chamber substrate compositions. The maximum power density among all assembled SMFCs was determined to be 231.18 mW/m2, generated by coconut waste. This model’s bioelectricity production was enhanced by adding organic compost to the anodic chamber, which acts as a catalyst in the system. The maximum power density of 788.58 mW/m2 was attained using a high proportion of coconut waste (CW) and organic compost. These results show that the higher percentage of lignin in CW improved the bioelectricity of SMFC.
... Due to the biological factors that can affect the overall performance of MFCs, including bioelectricity generation and operational cost, the substrate has received considerable attention (Ullah & Zeshan 2020). Numerous studies have examined the utilization of organic compounds derived from food and plant waste (Hongzhi et al. 2018;Qingliang et al. 2017). The majority of studies have concentrated on liquid solid waste as opposed to solid waste. ...
This study investigated the utilization of bamboo leaf waste and two varieties of bacterial sources, chicken manure and effective microorganism, in a microbial fuel cell (MFC) at three substrate concentrations (40 g/liter, 80 g/liter, and 160 g/liter). The primary objective was to investigate the kinetics of bacterial growth at various substrate concentrations in the MFC, as well as the effect of light conditions and pH on MFC power generation. The MFC had dual chambers with graphite electrodes serving as the cathode and anode. Within 72 h, the highest power density of 90.05 mV was attained using the highest substrate concentration of bamboo leaf waste and chicken manure during the logarithmic growth phase, albeit with a shorter duration. The longest sustained phase of bacterial activity was observed during the stationary phase, at the highest substrate concentration of 160 g/liter, followed by 80 g/liter and 40 g/liter. These results indicate that the logarithmic phase is the optimal time for bacterial activity in the MFC. However, attaining long-term stability in power generation in the logarithmic phase requires careful parameter optimization. ABSTRAK Penyelidikan ini mengkaji penggunaan sisa daun buluh dan dua jenis punca bakteria, tahi ayam dan mikroorganisma berkesan, dalam sel bahan api mikrob (MFC) pada tiga kepekatan substrat (40 g/liter, 80 g/liter dan 160 g/liter). Objektif utama adalah untuk mengkaji kinetik pertumbuhan bakteria pada pelbagai kepekatan substrat dalam MFC, serta kesan keadaan cahaya dan pH pada penjanaan kuasa MFC. MFC mempunyai dua ruang dengan elektrod grafit berfungsi sebagai katod dan anod. Dalam masa 72 jam, ketumpatan kuasa tertinggi 90.05mV telah dicapai menggunakan kepekatan substrat tertinggi sisa daun buluh dan baja ayam semasa fasa pertumbuhan logaritma, walaupun dengan tempoh yang lebih singkat. Fasa paling lama berterusan aktiviti bakteria diperhatikan semasa fasa pegun, pada kepekatan substrat tertinggi 160 g/liter, diikuti oleh 80 g/liter dan 40 g/liter. Keputusan ini menunjukkan bahawa fasa logaritma adalah masa yang optimum untuk aktiviti bakteria dalam MFC. Walau bagaimanapun, untuk mencapai kestabilan jangka panjang dalam fasa logaritma untuk penjanaan kuasa memerlukan pengoptimuman parameter yang teliti. Kata kunci: Baja ayam; daun buluh; kepekatan substrat; penjanaan bioelektrik; sel bahan api mikrob 1856
... However, several complex organics present in the BDW and BSW are challenging to biodegrade by indigenous microorganisms in MFCs. High COD removal and coulombic efficiency indicate that the indigenous microorganism present in BSY-MFC and BS-MFC have effectively utilized the organic materials available in BSW [44]. In cycle 3, maximum COD removal was obtained from BSY-MFC (88.8%), which was 18% higher than the BDY-MFC (45%). ...
Microbial fuel cells (MFCs) are considered as an emerging and cost-effective technology for treating organic waste along with bioelectricity generation. The present study evaluates the performance of S. cerevisiae-based H-shaped microbial fuel cell with banana peel waste as substrate, operated for 30 days in three cycles. Dried banana peel and banana slurry substrates were prepared with initial COD of 1126 ± 41 mg. L⁻¹ and 1366 ± 64 mg. L⁻¹ respectively. Dried banana peel powder was fed into two MFCs, one with no inoculant and the other with S. cerevisiae. Dried banana peel powder without inoculant yielded negligible power output, whereas dried banana peel powder with S. cerevisiae generated a maximum power density of 2.2 ± 0.1 mW m⁻². The banana peel slurry was fed into two different MFCs one was with S. cerevisiae and another was without S. cerevisiae. Banana slurry with S. cerevisiae generated a maximum power output of 86.9 ± 0.4 mW. m⁻². Banana peel slurry without inoculation, generated a maximum power output of 44.6 ± 0.8 mW. m⁻². Microbial community analysis indicated that the high-power output obtained from banana slurry-based MFCs was due to the presence of indigenous microbial consortia. Up to 70–88% COD removal was recorded in MFCs with banana slurry, however, 18–44% of COD removal was observed in MFCs with dried banana peel powder. It was also observed that the simple saccharides available in banana peel waste were consumed by S. cerevisiae and other indigenous microbes in the anode chamber. The microbial community released electrons in the anode chamber, which were responsible for voltage generation in MFC.
... Asefi et al. [86] produced a 422 mW/m 2 power density with a high COD removal efficiency of almost 87% using canteen waste with permanganate as the cathode of the MFC. Food waste ethanol fermentation stillage in a 120 mL single-chamber MFC with graphite and titanium as the material electrodes at the anode and cathode generated 0.29 V and 1.4 mA with a medium percentage of COD removal efficiency of around 70% [87], whereas a better power efficiency was found in a study by Gao et al. [88] of 612 mW/m 2 with a 62% COD removal efficiency. Household and kitchen waste can also be a good source for MFC bioenergy production. ...
... The total power produced by distillery wastewater in a two-chamber MFC with a salt-agar bridge (four in a series MFC connection) reached 347 mW [210]. Distilled fermentation broth from food waste used after pretreatment in a 120 mL single-chamber air-cathode MFC and graphite felt as the anode generated 0.29 V and 1.4 mA with a sufficient COD removal efficiency of 70% [87], whereas aromatic and humic-acid-like substances could not be degraded. Recent studies have verified that an enhanced organic load of distillery wastewater can increase power efficiency as well as organic matter degradation in a dual-chamber MFC with polyacrylic sheet electrodes [211], whereas others have demonstrated that lower-strength distillery wastewater can generate more power compared to full-strength wastewater [212]. ...
... The 70% COD removal efficiency stated by Ma et al. [87] was surpassed only by the Mohanakrishna et al. [215] study in a single-chamber MFC with plain graphite plates as the electrodes reaching almost 73%, whereas other studies mentioned a COD removal efficiency of between 54 and 68% [216][217][218][219]. Until now, a combination of anaerobic fluidized bed and MFC led to the maximum COD removal efficiency of 80-90% using alcohol distillery wastewater [220]. Despite the low COD removal efficiency, Hamza et al. [218] reported the maximum recorded power density of 25,194.8 ...
High-energy consumption globally has raised questions about the low environmentally friendly and high-cost processes used until now for energy production. Microbial fuel cells (MFCs) may support alternative more economically and environmentally favorable ways of bioenergy production based on their advantage of using waste. MFCs work as bio-electrochemical devices that consume organic substrates in order for the electrogenic bacteria and/or enzyme cultures to produce electricity and simultaneously lower the environmental hazardous value of waste such as COD. The utilization of organic waste as fuels in MFCs has opened a new research path for testing a variety of by-products from several industry sectors. This review presents several organic waste substrates that can be employed as fuels in MFCs for bioenergy generation and the effect of their usage on power density, COD (chemical oxygen demand) removal, and Coulombic efficiency enhancement. Moreover, a demonstration and comparison of the different types of mixed waste regarding their efficiency for energy generation via MFCs are presented. Future perspectives for manufacturing and cost analysis plans can support scale-up processes fulfilling waste-treatment efficiency and energy-output densities.
... The rapid generation of voltage in the initial several days was due to the bacteria and chemical compositions of the solutions present in the system, which needed some time to form the electroactive biofilm on the anode electrode [20,21]. According to Ma et al. (2020), voltage values gradually decrease in this type of substrate, because biodegradable components are easily exhausted, and the components that are more difficult to decompose are used to produce electricity at the end of the process [22]. These results are better than those obtained by Prasidha W. (2020), in which the author used food waste (fruit and vegetable waste) as leached fuel, obtaining peak voltages of 404 mV on the eighth day, and then they slowly decayed until the last day of monitoring; he attributed this phenomenon to the fact that the bacteria began to die due to nutrient depletion [23]. ...
The environmental problems caused by the excessive use of fossil fuels for electricity generation have led to the development of new technologies. Microbial fuel cells constitute a technology that uses organic sources for electricity generation. This research gives a novel means of using Golden Berry waste as fuel for electricity generation through microbial fuel cells made at low cost, achieving current and voltage peaks of 4.945 ± 0.150 mA and 1.03 ± 0.02 V, respectively. Conductivity values increased up to 148 ± 1 mS/cm and pH increased up to 8.04 ± 0.12 on the last day. The internal resistance of cells was 194.04 ± 0.0471 Ω, while power density was 62.5 ± 2 mW/cm2 at a current density of 0.049 A/cm2. Transmittance peaks of the Fourier-transform infrared (FTIR) spectrum showed a decrease when comparing the initial and final spectra, while the bacterium Stenotrophomonas maltophilia was molecularly identified with an identity percentage of 99.93%. The three cells connected in series managed to generate 2.90 V, enough to turn on a TV remote control. This research has great potential to be scalable if it is possible to increase the electrical parameters, generating great benefits for companies, farmers, and the population involved in the production and marketing of this fruit.
... BET (Brunauer, Emmett and Teller) surface area of the materials is given in Table S2. To increase adhesion by degreasing and removing organic matter, all materials were pre-soaked in a mixture of ethanol and acetone (1:1) (Ma et al., 2018), followed by two washing in distilled water, after which they were dried at 48°C for 24 h. ...
The activation of direct interspecies electron transfer (DIET) by the supplementation of conductive materials is one of the effective and available methods to enhance anaerobic digestion (AD). Microorganisms that colonize the surface of these materials form biofilms, the study of which could provide new insights into the character of the DIET process and its effect on AD. The present study focused on AD performance, microbial community, as well as morphological and topological features of biofilms on various materials used to promote DIET during AD of low-concentration swine manure. The best AD characteristics were observed in stainless steel mesh (SM)/digested cow manure (CM) and polyester felt (PF)/digested sewage sludge (SS) combinations used as material/inoculum, respectively. Thus, potential methane yields in CM-SM and SS-PF were up to 26.4% and 26.2% higher compared to the corresponding controls. Microbial analysis of biofilms revealed the dominance of putatively syntrophic bacteria of the MBA03 group of the Limnochordia class in CM inoculated reactors, and syntrophic proteolytic bacteria of the genus Coprothermobacter and acetogenic Clostridium sensu stricto 1, known for their ability to carry out DIET, in SS inoculated reactors. Biofilms on non-conductive materials contained pili-like structures, which were observed only in SS inoculated reactors. Polyester felt tended to biofoul better than carbon felt, resulting in up to 2.8, 3.2 and 1.8 higher nucleic acid, extracellular polymeric substances, and total biomass content, respectively, depending on the inoculum. These results provide new insights into the different types of DIET that can occur in low-loaded AD systems with attached growth.
... However, several complex organics present in the BDW and BSW are challenging to biodegrade by indigenous microorganisms in MFCs. High COD removal and coulombic efficiency indicate that the indigenous microorganism present in BSY-MFC and BS-MFC have effectively utilized the organic materials available in BSW [44]. In cycle 3, maximum COD removal was obtained from BSY-MFC (88.8%), which was 18% higher than the BDY-MFC (45%). ...
... BET (Brunauer, Emmett and Teller) surface area of the materials is given in Table S2. To increase adhesion by degreasing and removing organic matter, all materials were pre-soaked in a mixture of ethanol and acetone (1:1) (Ma et al., 2018), followed by two washing in distilled water, after which they were dried at 48°C for 24 h. ...
The present study focused on anaerobic digestion (AD) performance, microbial community, as well as morphological and topological features of biofilms on various materials used to promote direct interspecies electron transfer (DIET) during AD of low-concentration swine manure. The best AD kinetics were observed in stainless steel mesh/digested cow manure (CM) and polyester felt/digested sewage sludge (SS) combinations used as material/inoculum, respectively. Microbial analysis of biofilms revealed the dominance of putatively syntrophic bacteria of the MBA03 group of the Limnochordia class in CM inoculated reactors, and syntrophic proteolytic bacteria of the genus Coprothermobacter and acetogenic Clostridium sensu stricto 1 , known for their ability to carry out DIET, in SS inoculated reactors. Biofilms on non-conductive materials contained pili-like structures, which were observed only in SS inoculated reactors. Polyester felt had denser biofilms than carbon felt, regardless of the inoculum used. These results provide new insights into the different types of DIET that can occur in low-loaded AD systems with attached growth.
... Doping resulted in changes in functional group and an increase in the number of active sites, thereby increasing the oxygen reduction reaction catalytic activity. The bacterial cellulose-based catalyst was coated on to an air diffusion layer (Ma et al., 2018) and utilized as the cathode in SCMFCs with activated sludge as the inoculum. The results of this study were compared with another similar work that employed a platinum-based catalyst (Li et al., 2019a). ...
... Bacterial cellulose and its modification as catalyst for cathode in MFC. Note: BC: bacterial cellulose, P-BC: P-doped bacterial cellulose, P-Cu-BC: P, Cu-co doped bacterial cellulose [adapted from the studies byMa et al., 2018 andLi et al., 2019a]. ...
Microbial fuel Cells (MFCs) are an emerging technology for converting organic waste into electricity, thus providing
potential solution to energy crises along with eco-friendly wastewater treatment. The electrode properties
and biocatalysts are the major factors affecting electricity production in MFC. The electrons generated during microbial
metabolism are captured by the anode and transferred towards the cathode via an external circuit, causing
the flow of electricity. This flow of electrons is greatly influenced by the electrode properties and thus, much
effort has been made towards electrode modification to improve the MFC performance. Different semiconductors,
nanostructured metal oxides and their composite materials have been used to modify the anode as they possess
high specific surface area, good biocompatibility, chemical stability and conductive properties. The cathode
materials have also been modified using metals like platinum and nano-composites for increasing the redox potential,
electrical conductivity and surface area. Therefore, this paper reviews the recent developments in the
modification of electrodes towards improving the power generation capacity of MFCs.
