Research Library

R Sudarman, A Zaeni, I Usman et al.

Journal of Physics: Conference Series · 2020

Abstract Marine sediments of Kendari Bay has the potential as an alternative source of electrical energy through sediment microbial fuel cell (SMFC) due to the high level of sedimentation. This study aims to optimize the amount of electrical voltage that can be generated through the SMFC system using stacked SMFC in the form of a series connection. The research methods include determining the sampling location, physical-chemical properties measurement of sediments, SMFC assembly (single and stacked SMFC), and electrical voltage measurement. Three station points representing the overall condition of Kendari Bay are determined as sampling locations. The result shows that there was a decrease in the organic matter content of the sediment substrate after the use of SMFC namely organic carbon from 2.78 percent to be 2.68 percent due to microbial activity in sediments. The single SMFC from station 2 (S2) can produce the maximum electrical voltage of 438 mV which then optimized using stacked SMFC in series connection. The maximum electrical voltage of 2.174V can be obtained using stacked SMFC. These results show that marine sediments of Kendari Bay is interesting as an alternative energy source through SMFC and stacked SMFC could optimize the amount of electrical voltage from single SMFC.

Xiuping Zhu, Bruce E Logan

Bioresource technology · 2013

Mineral carbonation can be used for CO2 sequestration, but the reaction rate is slow. In order to accelerate mineral carbonation, acid generated in a microbial electrolysis desalination and chemical-production cell (MEDCC) was examined to dissolve natural minerals rich in magnesium/calcium silicates (serpentine), and the alkali generated by the same process was used to absorb CO2 and precipitate magnesium/calcium carbonates. The concentrations of Mg(2+) and Ca(2+) dissolved from serpentine increased 20 and 145 times by using the acid solution. Under optimal conditions, 24 mg of CO2 was absorbed into the alkaline solution and 13 mg of CO2 was precipitated as magnesium/calcium carbonates over a fed-batch cycle (24h). Additionally, the MEDCC removed 94% of the COD (initially 822 mg/L) and achieved 22% desalination (initially 35 g/L NaCl). These results demonstrate the viability of this process for effective CO2 sequestration using renewable organic matter and natural minerals.

A Y Goren, D N Eskisoy, S Genisoglu et al.

The Science of the total environment · 2024

The scarcity and contamination of freshwater resources are extremely critical issues today, and the expansion of water reuse has been considered as an option to decrease its impact. Therefore, the reuse of microbial desalination (MDC)-treated spent geothermal brine for agricultural purposes arises as a good solution to prevent water contamination and provide sustainable water usage. In this study, the potential of treated spent geothermal water from MDC system as a nutrient solution for the hydroponic cultivation of lettuce was evaluated. The effects of different water samples (Hoagland solution (R1) as a control, MDC-treated water (R2), 1:1, v/v mixture of MDC-treated water and Hoagland solution (R3), 4:1, v/v mixture of MDC-treated water and Hoagland solution (R4), and tap water (R5)) on lettuce growth were considered. The application of R3 and R4 samples for hydroponic lettuce cultivation was promising since the lettuce plants uptake sufficient nutrients for their growth and productivity with low toxic metal concentrations. In addition, the chlorophyll-a, chlorophyll-b, and carotene contents of lettuce were in the range of 1.045-2.391 mg/g, 0.761-1.986 mg/g, and 0.296-0.423 mg/g in different water samples, respectively. The content of chlorophyll-a was highest in R1 (2.391 mg/g), followed by R3 (2.371 mg/g). Furthermore, the health risk assessment of heavy metal accumulations in the lettuce plants cultivated in the various water samples was determined. Results showed that heavy metal exposure via lettuce consumption is unlikely to suffer noticeable adverse health problems with values below the permissible limit value.

Soheil Aber, Zhining Shi, Ke Xing et al.

Global challenges (Hoboken, NJ) · 2022

In view of increasing threats arising from the shortage of fresh water, there is an urgent need to propose sustainable technologies for the exploitation of unconventional water sources. As a derivative of microbial fuel cells (MFCs), microbial desalination cell (MDC) has the potential of desalinating saline/brackish water while simultaneously generating electricity, as well as treating wastewater. Therefore, it is worth investigating its practicability as a potential sustainable desalination technology. This review article first introduces the fundamentals and annual trends of MDCs. The desalination of diverse types of solutions using MDCs along with their life cycle impact assessment (LCIA)  and economic analysis is studied later. Finally, limitations and areas for improvement, prospects, and potential applications of this technology are discussed. Due to the great advantages of MDCs, improving their design, building materials, efficiency, and throughput will offer them as a significant alternative to the current desalination technologies.

Catarina M Paquete, Miriam A Rosenbaum, Lluís Bañeras et al.

Bioresource technology · 2021

Electroactive microorganisms can exchange electrons with other cells or conductive interfaces in their extracellular environment. This property opens the way to a broad range of practical biotechnological applications, from manufacturing sustainable chemicals via electrosynthesis, to bioenergy, bioelectronics or improved, low-energy demanding wastewater treatments. Besides, electroactive microorganisms play key roles in environmental bioremediation, significantly impacting process efficiencies. This review highlights our present knowledge on microbial interactions promoting the communication between electroactive microorganisms in a biofilm on an electrode in bioelectrochemical systems (BES). Furthermore, the immediate knowledge gaps that must be closed to develop novel technologies will also be acknowledged.

S. ThamizhSuganya, P. Balaganesan, L. Rajendran

International Journal of Advanced Research in Science, Communication and Technology · 2021

Mathematical modeling of biohydrogen production in microbial electrolysis cell reactor is discussed. This study explains the mathematical model for the production of hydrogen from a wastewater batch reactor, and it contains a system of non-linear equations. The non-linear differential equation of this model is solved by the Homotopy perturbation method. The approximate analytical expression of this model, concentration of substrate, anodophilic microorganisms, acetoclastic microorganism, hydrogenotrophic microorganisms, and Oxidized mediator are obtained. The effect of various values of the parameters on the reactions is discussed. The analytical solutions are also compared with simulation results and satisfactory the agreement is noted.

Li-Li Wan, Xiao-Jing Li, Guo-Long Zang et al.

RSC Advances · 2014

Solar energy, a microbial electrolysis cell (MEC) and a microbial fuel cell were combined as a new MEC system for hydrogen production.

Chunyan Li, Dongchao Guo, Yan Dang et al.

Journal of environmental management · 2023

Bioelectrochemical Systems (BESs) leverage microbial metabolic processes to either produce electricity by degrading organic matter or consume electricity to assist metabolism, and can be used for various applications such as energy production, wastewater treatment, and bioremediation. Given the intricate mechanisms of BESs, the application of artificial intelligence (AI)-based methods have been proposed to enhance the performance of BESs due to their capability to identify patterns and gain insights through data analysis. This review focuses on the analysis and comparison of AI algorithms commonly used in BESs, including artificial neural network (ANN), genetic programming (GP), fuzzy logic (FL), support vector regression (SVR), and adaptive neural fuzzy inference system (ANFIS). These algorithms have different features, such as ANN's simple network structure, GP's use in the training process, FL's human-like thought process, SVR's high prediction accuracy and robustness, and ANFIS's combination of ANN and FL features. The AI-based methods have been applied in BESs to predict microbial communities, products or substrates, and reactor performance, which can provide valuable information and improve system efficiency. Limitations of AI-based methods for predicting and optimizing BESs and recommendations for future development are also discussed. This review demonstrates the potential of AI-based methods in optimizing BESs and provides valuable information for the future development of this field.

Xue Ning, Richen Lin, Richard O'Shea et al.

iScience · 2021

Biomethane is suggested as an advanced biofuel for the hard-to-abate sectors such as heavy transport. However, future systems that optimize the resource and production of biomethane have yet to be definitively defined. This paper assesses the opportunity of integrating anaerobic digestion (AD) with three emerging bioelectrochemical technologies in a circular cascading bioeconomy, including for power-to-gas AD (P2G-AD), microbial electrolysis cell AD (MEC-AD), and AD microbial electrosynthesis (AD-MES). The mass and energy flow of the three bioelectrochemical systems are compared with the conventional AD amine scrubber system depending on the availability of renewable electricity. An energy balance assessment indicates that P2G-AD, MEC-AD, and AD-MES circular cascading bioelectrochemical systems gain positive energy outputs by using electricity that would have been curtailed or constrained (equivalent to a primary energy factor of zero). This analysis of technological innovation, aids in the design of future cascading circular biosystems to produce sustainable advanced biofuels.

Xi Chen, Peng Liang, Xiaoyuan Zhang et al.

Bioresource technology · 2015

Bioelectrochemical systems (BESs) are integrated water treatment technologies that generate electricity using organic matter in wastewater. In situ use of bioelectricity can direct the migration of ionic substances in a BES, thereby enabling water desalination, resource recovery, and valuable substance production. Recently, much attention has been placed on the microbial desalination cells in BESs to drive water desalination, and various configurations have optimized electricity generation and desalination performance and also coupled hydrogen production, heavy metal reduction, and other reactions. In addition, directional transport of other types of charged ions can remediate polluted groundwater, recover nutrient, and produce valuable substances. To better promote the practical application, the use of BESs as directional drivers of ionic substances requires further optimization to improve energy use efficiency and treatment efficacy. This article reviews existing researches on BES-driven directional ion transport to treat wastewater and identifies a few key factors involved in efficiency optimization.

S V Ramanaiah, K Chandrasekhar, Cristina M Cordas et al.

Environmental pollution (Barking, Essex : 1987) · 2023

Producing food by farming and subsequent food manufacturing are central to the world's food supply, accounting for more than half of all production. Production is, however, closely related to the creation of large amounts of organic wastes or byproducts (agro-food waste or wastewater) that negatively impact the environment and the climate. Global climate change mitigation is an urgent need that necessitates sustainable development. For that purpose, proper agro-food waste and wastewater management are essential, not only for waste reduction but also for resource optimization. To achieve sustainability in food production, biotechnology is considered as key factor since its continuous development and broad implementation will potentially benefit ecosystems by turning polluting waste into biodegradable materials; this will become more feasible and common as environmentally friendly industrial processes improve. Bioelectrochemical systems are a revitalized, promising biotechnology integrating microorganisms (or enzymes) with multifaceted applications. The technology can efficiently reduce waste and wastewater while recovering energy and chemicals, taking advantage of their biological elements' specific redox processes. In this review, a consolidated description of agro-food waste and wastewater and its remediation possibilities, using different bioelectrochemical-based systems is presented and discussed together with a critical view of the current and future potential applications.

Durga Madhab Mahapatra, Puranjan Mishra, Sveta Thakur et al.

Trends in biotechnology · 2021

Bioelectrochemical systems (BESs) are highly evolved and sophisticated systems that produce bioenergy via exoelectrogenic microbes. Artificial intelligence (AI) helps to understand, relate, model, and predict both process parameters and microbial diversity, resulting in higher performance. This approach has revolutionized BESs through highly advanced computational algorithms that best suit the systems' architecture.

Tianwen Zheng, Jin Li, Yaliang Ji et al.

Frontiers in bioengineering and biotechnology · 2019

Bioelectrochemical systems are revolutionary new bioengineering technologies which integrate microorganisms or enzymes with the electrochemical method to improve the reducing or oxidizing metabolism. Generally, the bioelectrochemical systems show the processes referring to electrical power generation or achieving the reducing reaction with a certain potential poised by means of electron transfer between the electron acceptor and electron donor. Researchers have focused on the selection and optimization of the electrode materials, design of electrochemical device, and screening of electrochemically active or inactive model microorganisms. Notably, all these means and studies are related to electron transfer: efflux and consumption. Thus, here we introduce the basic concepts of bioelectrochemical systems, and elaborate on the extracellular and intracellular electron transfer, and the hypothetical electron transfer mechanism. Also, intracellular energy generation and coenzyme metabolism along with electron transfer are analyzed. Finally, the applications of bioelectrochemical systems and the prospect of microbial electrochemical technologies are discussed.

Atieh Ebrahimi, Muttucumaru Sivakumar, Craig McLauchlan

Journal of environmental management · 2020

The past decade has seen the rapid development of constructed wetland-microbial fuel cell (CW-MFC) technology in many aspects. The first publication on the combination of constructed wetland (CW) and microbial fuel cell (MFC) appeared in 2012, subsequently, research on the subject has grown exponentially to improve the performance of CW-MFCs in their dual roles of wastewater treatment and power generation. Although significant research has been conducted on this technology worldwide, a comprehensive and critical review of effective controlling parameters is lacking. More broadly, research is needed to draw up-to-date conclusions on recent developments and to identify knowledge gaps for further studies. This review paper systematically enumerates and reviews research studies published in this area to determine the key design factors and their role in CW-MFC performance. Moreover, a taxonomy of all CW-MFC design parameters has been synthesised from the literature. Importantly, this original work provides a comprehensive conceptual framework for future researchers, designers, builders, and users to understand CW-MFC technology. Within the taxonomy, parameters are placed in three main categories (physical/environmental, chemical, and biological/electrochemical) and comprehensive details are given for each parameter. Finally, a comprehensive summary of the parameters has been tabulated showing their impact on CW-MFC operation, design recommendations from literature, and the significant research gaps that this review has identified within the existing literature. It is hoped that this paper will provide a clear and rich picture of this technology at its current stage of development and furthermore, will facilitate a deeper understanding of CW-MFC performance for long-term and large-scale development.

Kavya Arun Dwivedi, Song-Jeng Huang, Chin-Tsan Wang

Chemosphere · 2021

The conflict between climate change and growing global energy demand is an immense sustainability challenge that requires noteworthy scientific and technological developments. Recently the importance of microbial fuel cell (MFC) on this issue has seen profound investigation due to its inherent ability of simultaneous wastewater treatment, and power production. However, the challenges of economy-related manufacturing and operation costs should be lowered to achieve positive field-scale demonstration. Also, a variety of different field deployments will lead to improvisation. Hence, this review article discusses the possibility of integration of MFC technology with various technologies of recent times leading to advanced sustainable MFC technology. Technological innovation in the field of nanotechnology, genetic engineering, additive manufacturing, artificial intelligence, adaptive control, and few other hybrid systems integrated with MFCs is discussed. This comprehensive and state-of-the-art study elaborates hybrid MFCs integrated with various technology and its working principles, modified electrode material, complex and easy to manufacture reactor designs, and the effects of various operating parameters on system performances. Although integrated systems are promising, much future research work is needed to overcome the challenges and commercialize hybrid MFC technology.

Payel Choudhury, Uma Shankar Prasad Uday, Tarun Kanti Bandyopadhyay et al.

Bioengineered · 2017

There is an urgent need to find an environment friendly and sustainable technology for alternative energy due to rapid depletion of fossil fuel and industrialization. Microbial Fuel Cells (MFCs) have operational and functional advantages over the current technologies for energy generation from organic matter as it directly converts electricity from substrate at ambient temperature. However, MFCs are still unsuitable for high energy demands due to practical limitations. The overall performance of an MFC depends on microorganism, appropriate electrode materials, suitable MFC designs, and optimizing process parameters which would accelerate commercialization of this technology in near future. In this review, we put forth the recent developments on microorganism and electrode material that are critical for the generation of bioelectricity generation. This would give a comprehensive insight into the characteristics, options, modifications, and evaluations of these parameters and their effects on process development of MFCs.

Khaled Elmaadawy, Bingchuan Liu, Jingping Hu et al.

Journal of environmental sciences (China) · 2019

Over half of century, sanitary landfill was and is still the most economical treatment strategy for solid waste disposal, but the environmental risks associated with the leachate have brought attention of scientists for its proper treatment to avoid surface and ground water deterioration. Most of the treatment technologies are energy-negative and cost intensive processes, which are unable to meet current environmental regulations. There are continuous demands of alternatives concomitant with positive energy and high effluent quality. Microbial fuel cells (MFCs) were launched in the last two decades as a potential treatment technology with bioelectricity generation accompanied with simultaneous carbon and nutrient removal. This study reviews capability and mechanisms of carbon, nitrogen and phosphorous removal from landfill leachate through MFC technology, as well as summarizes and discusses the recent advances of standalone and hybrid MFCs performances in landfill leachate (LFL) treatment. Recent improvements and synergetic effect of hybrid MFC technology upon the increasing of power densities, organic and nutrient removal, and future challenges were discussed in details.

D Akman, K Cirik, S Ozdemir et al.

Global NEST Journal · 2019

<p>The main aim of this study is to investigate the simultaneous azo dye removal and bioelectricity production at sulfate reducing conditions in continuously-fed dual-chamber microbial fuel cell (MFC). Initially, optimization of sulfate reduction was performed at different sulfate concentrations (100-900 mg/L) and the constant COD of 1000 mg/L, corresponding to COD/sulfate ratio of 1.11-10, and varying HRT of 12-48h. Optimum COD/sulfate ratio and HRT was found 1.66 and 36h, respectively, corresponding to 96% COD removal, 44% sulfate removal and yielded about 24 W/m2 power density. Further, MFC was fed with azo dye containing (50-1000 mg/L) simulated wastewater to evaluate dye removal performance of sulfate reducing bacteria. Addition of azo dye slightly enhanced the power production to 26 W/m2, the highest value obtained during our study, compared to azo dye lacking study periods. Sulfate and COD removals were adversely affected at azo dye concentrations over 300 mg/L and 150 mg/L, respectively. Additionally, color removal performance of MFC was excellent however, chemical azo dye reduction out-competed with enzymatic reduction at high azo dye levels (>500 mg/L) leading to a poor sulfate (<15%) and COD (<45%) removal and recovery of azo dye reduction efficiency to 91%.</p>

Elif DURNA PİŞKİN, Nevim NevimGENÇ

Research Square · 2022

Abstract In microbial fuel cells (MFC), oxidation and reduction processes occur simultaneously. In this study, the operating conditions affecting oxidation-reduction and electricity generation of MFC were optimized using the Taguchi Experimental Design model. Optimization was carried out for maximum power density, coulombic efficiency, azo dye removal and COD removal. With the determined optimum conditions (cathode pH of 3.0, cathode oxygen status of anaerobic, anode substrate of pre-treated, external resistance of 100 Ω, cathode electrode type of plain carbon, cathode electrode surface of 22 cm 2 , cathode conductivity of 20 µs/cm), 177.031 mW/m 2 power density, 7.50% coulombic efficiency, 91.266% azo dye removal efficiency and 21.612% COD removal efficiency were obtained. From the Pareto analysis, it was determined that the power density, coulombic efficiency and COD removal efficiency were most affected by the substrate type at the anode, and the azo dye removal was most affected by the catholyte pH. With the polarization curve, it has been determined that the maximum power density is 145.11 mW/m 2 and the internal resistance of the optimum MFC system is 243.3 Ω. The cyclic voltammogram performed with the optimum experiment was associated with oxidation and reduction reactions.

Tharangika Ranatunga, Ken Hiramatsu, Takeo Onishi et al.

Reviews in Agricultural Science · 2018

Denitrification, which converts soil nitrogen to nitrogen gas, involves a great loss of nitrogen fertilizer. Controlling the process of denitrification rate could help reducing the losses of applied nitrogen fertilizer in crop fields. Fertilizer nitrogen is one of the major concerns due to the high energy demand for its production. Since flooded rice soils are known to have strong denitrifying activity, innovative techniques are emerging as needs to improve nitrogen fertilizer retention efficiency in flooded rice soils. Nitrous oxide (N2O) emissions are not considered as significant, compared to that of methane (CH4) emissions from flooded rice soils, most probably due to its complete denitrification process with prolonged submergence that favors the production of nitrogen (N2) gas. This is due to a further reduction of N2O to N2. However, efficient use of nitrogen in the rice soils could have the benefits of saving energy costs that are being spent on nitrogen fertilizers in many developing countries. While conventional approaches are less efficient in controlling denitrification, technical solutions are emerging to solve this need. Technical solutions based on soil redox potential (Eh) for the control of denitrification have not been adequately covered. We propose that applicability of microbial fuel cell based on soil redox chemistry would be more promising for the control of denitrification in flooded rice soils.

Mohamed Farghali, Zhonghao Chen, Ahmed I. Osman et al.

Environmental Chemistry Letters · 2024

Abstract The circular economy requires advanced methods to recycle waste matter such as ammonia, which can be further used as a fuel and a precursor of numerous value-added chemicals. Here, we review methods for the recovery of ammonia from wastewater with emphasis on biological and physicochemical techniques, and their applications. Biological techniques involve nitrification, denitrification, and anammox processes and the use of membrane bioreactors. Physicochemical techniques comprise adsorption, membrane filtration, ion exchange, chemical precipitation, ammonia stripping, electrochemical oxidation, photocatalytic oxidation, bioelectrochemical systems, and membrane hybrid systems. We found that nitrification and anammox processes in membrane bioreactors stand out for their cost-effectiveness, reduced sludge production, and energy efficiency. The use of struvite precipitation is an efficient, environmentally friendly, and recyclable method for ammonia removal. Membrane hybrid systems are promising for ammonia recovery, nutrient concentration, and wastewater treatment, with applications in fertilizer production and water purification. Overall, nitrogen removal ranges from 28 to 100%, and nitrogen recovery ranges from 9 to 100%.

Aliyu Ishaq, Mohd Ismid Mohd Said, Shamila Azman et al.

Environmental Science and Pollution Research · 2023

Untreated landfill leachate can harm the environment and human health due to its organic debris, heavy metals, and nitrogen molecules like ammonia. Microbial fuel cells (MFCs) have emerged as a promising technology for treating landfill leachate and generating energy. However, high concentrations of total ammonia-nitrogen (TAN), which includes both ammonia and the ammonium ion, can impede MFC performance. Therefore, maintaining an adequate TAN concentration is crucial, as both excess and insufficient levels can reduce power generation. To evaluate the worldwide research on MFCs using landfill leachate as a substrate, bibliometric analysis was conducted to assess publication output, author-country co-authorship, and author keyword co-occurrence. Scopus and Web of Science retrieved 98 journal articles on this topic during 2011-2022; 18 were specifically evaluated and analysed for MFC ammonia inhibition. The results showed that research on MFC using landfill leachate as a substrate began in 2011, and the number of related papers has consistently increased every 2 years, totaling 4060 references. China, India, and the USA accounted for approximately 60% of all global publications, while the remaining 40% was contributed by 70 other countries/territories. Chongqing University emerged as one of the top contributors among this subject's ten most productive universities. Most studies found that maintaining TAN concentrations in the 400-800 mg L -1 in MFC operation produced good power density, pollution elimination, and microbial acclimatization. However, the database has few articles on MFC and landfill leachate; MFC ammonia inhibition remains the main factor impacting system performance. This bibliographic analysis provides excellent references and future research directions, highlighting the current limitations of MFC research in this area.

D. Gowthaman, A. Shamadhani Begum, S. Thamizh Suganya et al.

International Journal of Thermo-Fluid Systems and Sustainable Energy · 2025

This study presents an analytical mathematical model for an integrated microbial fuel cell--oxic--anoxic bioreactor (MFC--OB--ANB) system designed for simultaneous slaughterhouse wastewater treatment and energy recovery. The model incorporates bioelectrochemical oxidation, nitrification, and denitrification processes using acetate as a representative substrate. Closed-form analytical solutions are derived for substrate degradation, nitrogen transformation, current density, and system voltage. The effects of biofilm thickness, membrane conductivity, and influent substrate concentration on treatment efficiency and power generation are systematically investigated. Results reveal that enhanced biofilm conductivity and reduced membrane resistance significantly improve energy recovery, while optimized substrate loading enhances nitrogen removal performance. The proposed framework provides valuable insights for the design and optimization of integrated bioelectrochemical wastewater treatment systems.

Vibeke B. Karlsen, Gamunu Samarakoon, C. Dinamarca

Linköping Electronic Conference Proceedings · 2022

Sulphide (H2S, HS- and S2-) is an undesired by-product of biogas production processes. This modelling work in Aquasim was carried out to study three parallel processes related to sulphide in AD processes: 1) H2S liquid-gas mass transfer; 2) Acid-base equilibrium; and 3) Sulphide oxidation with three different electron acceptors; nitrate, oxygen, and a biotic anode with a given potential. Multiplicative Monod (biotic processes) and Nernst-Monod kinetics (bioelectrochemical process) provide the basis for the sulphide bio-oxidation processes. At the current stage, the model can be used to study sulphide bio-oxidation and the effect of relevant parameters, including initial biomass concentration, uptake rates, temperature, and pH. The model can be improved further by implementing anaerobic microbial processes as competing reactions. With the proposed improvements, the model can be a useful tool for calculating the chemical dosage or electrode potential required for sulphide removal. These calculations can be based on both the concentration of H2S(g) in the headspace (ppm) often available at full-scale plants and the concentration of sulphide (HS-(liq)) in effluent streams from the plants.

Kuleshova T.E., Panova G.G., Gall N.R. et al.

Technical Physics Letters · 2022

The experimental bioelectrochemical current source based on the concentration gradient of charge carriers in the root environment of plants has been created. A potential difference of about 70 mV is observed in the nutrient solution. It is gradually decreasing due to equalization of concentrations. The voltage increases to 200 mV when plant are placed in a cultivation system as the root system develops due to the intensification of diffusion processes. The potential-forming role of nitrate forms of nitrogen is shown on the example of lettuce grown according to the panoponics technology. The separation of electrical charges by the root system during the life of plants can become an alternative source of green energy. Keywords: rhizosphere, bioelectric potential, panoponics, green energy.

Umarat Santisukkasaem

Environment and Natural Resources Journal · 2025

The general daily maintenance of outdoor swimming pools includes the addition of chlorine for disinfection. Chlorine is a potentially hazardous chemical that is harmful to users, and its excessive addition could lead to health effects in swimmers while insufficient levels may result in inadequate disinfection. This study aimed to optimize chlorine management at the Silpakorn University swimming pool by analyzing the physical and chemical characteristics of outdoor pool water. Initial sampling revealed an unacceptably high residual chlorine concentration of 20 mg/L, exceeding regulatory standards. To address this, a chlorine management strategy was implemented. Chlorine adjustment was conducted by measuring the residual chlorine concentration and calculating the chlorine demand. Post-intervention results indicated that residual chlorine and pH levels were successfully brought within acceptable limits. Further analysis confirmed that parameters such as hardness, ammonia nitrogen, nitrite nitrogen, nitrate nitrogen, suspended and dissolved solids, and total and fecal coliform bacteria met safety standards. Recommendations were given to the pool caretaker, including the use of personal protective equipment (PPE) while handling chlorine, a precise measurement of chlorine (1 kg daily), and regular filtration tank maintenance at least twice a month. Besides improving social and environmental aspects, the optimized chlorine usage resulted in an estimated annual cost saving of $1,213.26 (1 USD ≈ 36.065 THB). This study highlights the importance of sustainable chlorine management in swimming pools, offering a practical approach that can be replicated in similar facilities.

Saleh Bufarwa

Research Square · 2022

Abstract Utilizing electrochemical and optical methods, a novel conjugated co-compound that contains the redox-active thiophene-EDTT units has been described. The electrochemical and spectroscopic characteristics of the molecule 5,7-bis(3-hexylthiophen-2-yl)-2,3-dihydrothieno[3,4-b][1, 4]dithiine are covered in this article. Ethylene3,4-dioxythiophene (EDTT), which is bound by bis-hexylthiophene units, appears as the central core. Tetrabutylammonium hexafluorophosphate (Bu 4 NPF 6 ) 0.1 M was used as the supporting electrolyte in cyclic voltammetry to study the material's redox properties, and electronic absorption Spectra in acetonitrile solution was used to study the material's optical properties. The monomer's electrochemical characteristics have resulted in a lower oxidation potential than its polymer. When compared to the polymer state, the optical band gap of the monomer has demonstrated a significant change.

T. Kuleshova, P. Zhelnacheva, Z. Gasieva et al.

Russian Journal of Biological Physics and Chemisrty · 2024

The work considers the effect of the nutrient solution composition on the potential difference formation in the root environment. Identification of possible potential-generating ions in bioelectrochemical systems based on electactive plant and microbial interactions was carried out. The electropotential difference in the root environment was measured when growing lettuce with a nutrient solution with a double increased content of magnesium sulfate, potassium chloride and potassium dihydortophosphate. Changes in the electrical conductivity of nutrient solutions in the process of lettuce growing and the differences in the pH and concentrations of calcium, potassium, ammonium, nitrate ions in the upper and lower electrode areas of bioelectrochemical systems are analyzed. An increase in the concentration of potassium chloride and potassium dihydortophosphate in a nutrient solution led to a decrease in both biomass and the average voltage value to 221 mV and 188 mV, respectively, relatively characteristic of the control option with a classic solution of the potential difference 213 mV. The doubling of the magnesium sulfate concentration, on the contrary, caused an increase in the potential difference to an average value of 263 mV and an increase in biomass by more than 30% relative to control. Probably, magnesium sulfate plays a potential role in the formation of electogenic reactions in the root environment.

Matthew Hardhi, Putty Ekadewi, Rita Arbianti et al.

E3S Web of Conferences · 2018

The increasingly adverse effects of climate change caused by a variety of fossil-based fuel demands an alternative to such fuel. Hydrogen is one of the potential renewable fuel that offers numerous advantages compared to its competitors. However, the dominant hydrogen production methods are still energy-heavy and dependent on fossil-based resources. Microbial electrolysis cell or MEC system is one of the leading solution towards replacing conventional hydrogen production method. A persistent downside to this system in the presence of methanogens that consumes the hydrogen product. This research proposes alternative biological method to control the methanogen colony by introducing isolates of denitrifying bacteria to the system which will act as inhibitor to hydrogenotrophic methanogen. The reactor implemented is a single-chambered, membrane-less 20-ml reactor. Net hydrogen yield produced in the cathodic headspace will be analyzed by gas chromatography (GC). Hydrogen yield for reactor with enriched cathode is expected to be higher in comparison to unenriched reactor, as nitrogen oxides produced during the metabolism of the denitrifiers were known to inhibit methanogen growth. Experimental results showed consistent higher H 2 yield in inoculated reactor compared to control reactor, where in the second cycle H 2 production increased 100% compared to the control.

Theresia Desy Askitosari, Amanda Larasati

E3S Web of Conferences · 2023

The widespread use of pesticides for agricultural purposes results in their presence in the environment. Pesticide occurrence is causing potential negative impacts on human health and environmental deterioration in general. One of the interdisciplinary field to implement a technology for converting and conserving resources is bioelectrochemistry. An integrated system based on bioelectrochemical processes, namely Bioelectrochemical System (BES), has been well developed to date. The application of BES to remove various materials in the bioremediation process has been well established in the combination with diverse technologies. The set up of integrated BES with Granular Activated Carbon (GAC) is one of the promising solutions to enhance the removal of the pesticide in water. The BES in situ has been implemented to remove contaminants in groundwater. This mini-review discusses the recent development of pesticide removal and environmental remediation using bioelectrochemical approaches, offering new insight into the big scope of green technology application.

Emmanuel Egbadon, Campbell O. Akujobi, Chris O. Nweke et al.

International Letters of Natural Sciences · 2016

This study aimed at the simultaneous treatment of wastewater obtained from swine and generation of bioenergy in form of electricity from the energy stored in the organic component of the wastewater. The Open circuit voltage, current, power density and microbiological and physicochemical parameters were monitored. An initial Open circuit voltage of 516mV, Current of 0.29mA, and Power density of 32.74mW/m 2 were recorded, which increased to give maximum Open Circuit Voltages of 836mV, Current of 0.49mA, and Power density of 88.45mW/m 2 . The results revealed that The Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), Organic carbon, Total Soluble solids (TSS), Ammonia, Ammonium and Ammonium-Nitrogen all showed percentage decrease of 85.92%, 51.74%, 78.16%, 98.87%, 55.87%, 55.79% and 55.90% respectively while parameters such as Total Dissolved Solids (TDS), Nitrate, Nitrate-Nitrogen, Phosphates, Phosphorus and Orthophosphates however increased after treatment to give a percentage increase of -273.60%, -131.65%, -134.85%, -168.77%, -159.26%, and -157.03% respectively. Bacteria isolates identified at the biofilms on the anode were Corynebacterium specie , Bacillus specie , Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Streptococcus faecalis . The results from this study further exacerbate the Bioelectricity production as well as wastewater treatment potentials of the Microbial Fuel Cell technology.

Aliyu, A. A., Dahiru, R.

UMYU Journal of Microbiology Research (UJMR) · 2024

Study’s Novelty/Excerpt This study presents an approach to enhancing microbial fuel cell (MFC) performance by employing phototrophic bacteria (PTB) and sustainable electrode materials, specifically a 3D anode electrode fabricated from reduced graphene oxide (rGO) and nickel (Ni) foam. By integrating morphological, biochemical, and molecular techniques to identify the electrochemically active PTB, the research achieved a significant eight-fold increase in power density using rGO-Ni electrodes compared to conventional Ni electrodes. This work underscores the potential of utilizing sustainable materials and PTB to improve MFC efficiency and economic viability, offering a promising direction for sustainable bioelectricity generation. Full Abstract Over the past years, despite intensified research on microbial fuel cells (MFC), low power densities were recorded, reducing the productivity and economic viability of the process. This necessitated testing various MFC configurations, fabricating various electrodes, and evaluating various substrate types and species of electrogenic microorganisms to improve MFC performance. Despite the dual advantage of phototrophic bacteria (PTB), metabolizing organic waste substances and generating electricity, less research was conducted on the bacterium. Although a significant amount of energy is generated using unsustainable (fossil-based) materials in electrode fabrication, this study focuses on using sustainable materials like carbon cloth and graphite to fabricate a 3D anode electrode to exploit the maximum energy generated by PTB. The PTB used in this study was identified through morphological characteristics and biochemical tests (catalase and oxidase) and confirmed using a molecular technique: 16S rRNA sequencing. Preliminary results indicated that the PTB was gram-negative, spherical in shape, non−motile, and facultatively anaerobic bacterium. Analysis of the 16S rRNA partial sequence was conducted in GenBank databases. 100 significant sequences with the lowest and highest similarities of 84.10% and 98.76% were recorded, respectively. Of these, 13 strains had the highest similarities of >90%, all belonging to the genus Dysgonomonas, with D. oryzarvi Dy73 (98.76%) as the closest. Reduced graphene oxide (rGO) used as the anode was prepared using Hummer’s method by depositing the rGO on nickel (Ni) foam which changed the colour of Ni from grey to black after depositing and annealing. In addition to the SEM images, which showed a continuous multi−layered 3D scaffold on the Ni, the cyclic voltammetry (CV) analyses indicated an increase in the electrochemical activities of the rGO−Ni electrode compared to Ni. The CV also confirmed the bacterium to be electrochemically active. The 100 mL glucose−fed two−chamber MFC were separately run with the Ni and rGO–Ni as anode electrodes in a batch mode for 11 days, while carbon cloth was used as the cathode for both runs. An approximate 0.58 W/m2 power density was recorded for Ni, but eight−fold of Ni’s, 4.9 W/m2was generated by rGO−Ni. The study demonstrated that using fabricated 3D rGO–Ni as anode electrode can increase the microbial adhesion and power density of bacterium in MFC, thereby providing a more applicable and sustainable alternative to bioelectricity generation.

ASHIMA SRIVASTAVA, SANDEEP GUPTA, PRATIBHA SINGH et al.

Pollution Research · 2022

Microbial fuel cell (MFC) is a green and promising alternative for saving the depleting nonrenewableresources. In the present research, MFC technology is utilized to bring aboutdetoxification of textile wastewater with simultaneous production of electricity. Textile wastewaterhas a high pH value, high concentrations of dyes, organic pollutants, suspended solids, chlorides,nitrates, heavy metals (high BOD and COD values). The high organic load in the wastewatermakes it function as the useful substrate for microorganisms in MFC. Experimental results showedthat MFC using textile wastewater gave excellent electrical output of 546 mV after 60 h of operationIt has been found under the operating conditions of the experiments, there was 90–95% reductionin colour, TDS, BOD and COD of the textile wastewater.

Marta Coma

Journal of Bioremediation & Biodegradation · 2012

Addressing the simultaneous removal of multiple coexisting groundwater contaminants poses a significant challenge, primarily because of their different physicochemical properties. Indeed, different chemical compounds may necessitate establishing distinct, and sometimes conflicting, (bio)degradation and/or removal pathways. In this work, we investigated the concomitant anaerobic treatment of toluene and copper in a single-chamber bioelectrochemical cell with a potential difference of 1 V applied between the anode and the cathode. As a result, the electric current generated by the bioelectrocatalytic oxidation of toluene at the anode caused the abiotic reduction and precipitation of copper at the cathode, until the complete removal of both contaminants was achieved. Open circuit potential (OCP) experiments confirmed that the removal of copper and toluene was primarily associated with polarization. Analogously, abiotic experiments, at an applied potential of 1 V, confirmed that neither toluene was oxidized nor copper was reduced in the absence of microbial activity. At the end of each experiment, both electrodes were characterized by means of a comprehensive suite of chemical and microbiological analyses, evidencing a highly selected microbial community competent in the biodegradation of toluene in the anodic biofilm, and a uniform electrodeposition of spherical Cu 2 O nanoparticles over the cathode surface.

B.G.Mahendra .

International Journal of Research in Engineering and Technology · 2013

Two microbial fuel cells were inoculated with activated sludge from Finland and operated under moderate (25 °C) and low (8 °C) temperatures. Operation under real urban wastewater showed similarities in chemical oxygen demand removal and voltage generated, although moderate temperature supported higher ammonium oxidation. Fungi disappeared in the microbial fuel cell operated at temperature of 25 °C. Archaea domain was dominated by methanogenic archaea at both temperature scenarios. Important differences were observed in bacterial communities between both temperatures, however generating similar voltage. The results supported that the implementation of microbial fuel cells in Nordic countries operating under real conditions could be successful, as well as suggested the flexibility of cold-adapted inoculum for starting-up microbial fuel cells, regardless of the operating temperature of the system, obtaining higher COD removal and voltage generation performances at low temperature than at moderate temperature.

Korneel Rabaey, Willy Verstraete

Trends in Biotechnology · 2005

Deepak Pant, Gilbert Van Bogaert, Ludo Diels et al.

Bioresource Technology · 2010

Bruce E. Logan, Ruggero Rossi, Ala’a Ragab et al.

Nature Reviews Microbiology · 2019

A vast array of microorganisms from all three domains of life can produce electrical current and transfer electrons to the anodes of different types of bioelectrochemical systems. These exoelectrogens are typically iron-reducing bacteria, such as Geobacter sulfurreducens, that produce high power densities at moderate temperatures. With the right media and growth conditions, many other microorganisms ranging from common yeasts to extremophiles such as hyperthermophilic archaea can also generate high current densities. Electrotrophic microorganisms that grow by using electrons derived from the cathode are less diverse and have no common or prototypical traits, and current densities are usually well below those reported for model exoelectrogens. However, electrotrophic microorganisms can use diverse terminal electron acceptors for cell respiration, including carbon dioxide, enabling a variety of novel cathode-driven reactions. The impressive diversity of electroactive microorganisms and the conditions in which they function provide new opportunities for electrochemical devices, such as microbial fuel cells that generate electricity or microbial electrolysis cells that produce hydrogen or methane.

Wenjie Liu

American Journal of Bioscience and Bioengineering · 2014

Taiki Adachi, T. Takei, Takumi Nishiyama et al.

Inorganic chemistry · 2026

Copper efflux oxidase (CueO) is involved in copper homeostasis in Escherichia coli by catalyzing the oxidation of cuprous ion (Cu + ) to cupric ion (Cu 2+ ). CueO has been studied as a direct electron transfer (DET)-type bioelectrocatalyst owing to its high dioxygen-reducing activity. Our previous study demonstrated reductive inactivation in the DET-type bioelectrocatalysis of CueO in the presence of Cu 2+ , which was known to facilitate substrate oxidation in solution. Considering the structural data, we hypothesized that eighth bound copper (Cu8) induced reductive inactivation. CueO variants deleting putative Cu8 ligands (His145, His406, and Met417) were characterized bioelectrochemically. As expected, the inactivation was significantly suppressed in H145A while being slightly suppressed in the H406A variant. In contrast, Cu 2+ tolerance was slightly decreased in the M417A variant. These results indicate that His145 and His406 are the main and auxiliary ligands, respectively, of Cu8 that induce reductive inactivation, whereas Met417 might contribute to stabilizing the Cu8 coordination sphere. Furthermore, kinetic analysis revealed that the deletion of Cu8 ligands affected both the binding and redox kinetics of the enzyme-substrate-copper complex. Additionally, Cu8-induced inactivation was observed using an enzymatic assay in solution. Therefore, reductive inactivation likely occurs in concert with biological Cu + oxidation, which may contribute to regulating the Cu 2+ /Cu + ratio.