Pengsha Zhao, Xinying Liu, Zheng Wang et al.

Fuel Cells • 2024

ABSTRACTAlgae–bacteria symbiosis (ABS) as a sustainable wastewater treatment process has drawn mounting attention. However, nontrivial CO2 emissions were still present in municipal wastewater treatment due to the inadequate carbon fixation efficiency of microalgae under low carbon level. The obtained UV‐induced mutant Chlorella vulgaris MIHL4 performed higher carbon fixation capability (14.5%) and biomass productivity (25.3%) with improved photosynthetic fluorescence parameters and enzyme activities compared to wild‐type C. vulgaris. Transcriptome analyses showed pathways related to the carbon fixation and carbon catabolism were significantly up‐regulated in MIHL4. Compared with ABS inoculated with wild‐type C. vulgaris, CO2 emissions were significantly reduced by 32.1%–38.3% in ABS inoculated with MIHL4, where the biomass growth, metabolic activity, and sludge granulation were enhanced. Chlorella responsible for carbon fixation was the dominant population (19.3%) in ABS inoculated with MIHL4, in which the abundance of functional microbes and genes associated with photosynthesis as well as nutrient removal increased.

Necla Altın, Başar Uyar

Biomass Conversion and Biorefinery • 2025

Abstract In this study, an algae-assisted microbial fuel cell (MFC) was developed to both treat horse manure wastewater and generate electricity. Carbon felt (CF) and graphite felt (GF) electrodes were modified with carbon nanotube (MWCNT) and nitric acid (HNO₃) to prepare different anodes and their effects on MFC performance were evaluated. The power density of 59 mW/m2 obtained with the CF-HNO₃ anode showed the highest value among all tested systems and was found to be 2.45 and 2.13 times higher than unmodified CF and GF anodes, respectively. Moreover, a 17% higher performance was achieved compared to the GF-HNO₃ anode. The higher performance of CF-HNO₃ compared to GF-HNO₃ can be attributed to the higher surface area of the carbon felt, improved proton conduction, and increased electrochemical activity after treatment with nitric acid. The modified CF-MWCNT and GF-MWCNT anodes produced power densities of 55 mW/m2 and 45 mW/m2, respectively. The Coulombic efficiency (CE) values obtained were in line with these results. The results reveal that nitric acid modification significantly increases the power output of MFCs by providing accelerated electron transfer on biofilms. This simple and effective method offers a new approach to develop low-cost and high-performance electrode materials for MFCs. Moreover, the analysis of algal biomass from the cathode chamber is in line with the existing literature and makes an important contribution towards sustainable energy solutions. The study stands out as a promising step towards the scalability and commercialization of MFCs. Furthermore, the findings can contribute to economic feasibility through low-cost modification techniques and support environmental sustainability. The findings contribute to economic feasibility and support environmental sustainability through low-cost modification techniques. Future studies can support the wider adoption of MFCs for industrial applications by investigating the effects of these modifications on long-term performance and compatibility with different wastewater types. This could accelerate the transition to sustainable energy solutions by promoting the wider use of MFCs in power generation and wastewater treatment.

Sahand Adibnia, Kevin George

Journal of Student Research • 2023

Microbial fuel cells (MFCs) are currently being researched as alternative energy sources with promising applications in wastewater treatment. However, in two-chamber designs, cathodic oxygen reduction is slow and limits MFC voltage. Biocathodes, cathodes containing microorganisms, show great promise for improving MFC performance. This study investigated how the microalgae Nannochloropsis affects cathodic oxygen reduction via a thermodynamic analysis of energy losses. Voltage, cathode pH, and cathode pO2 (partial pressure of oxygen) were measured in experimental MFCs containing Nannochloropsis biocathodes and compared to controls containing distilled water or abiotic algae media cathodes. Isolated Nanochloropsis cultures were also assayed. Under open circuit conditions, cathodic energy losses in experimental MFCs were 15% (p = 0.038597) and 19% (p = 0.042435) lower than distilled water and algae media controls, respectively. Experimental MFCs produced 73% higher power at 37% higher current density than distilled water MFCs. While the pH and pO2 of isolated Nannochloropsis cultures increased linearly each day, these measurements were constant in experimental MFC cathodes. This result suggests that participation in oxygen reduction reactions induces a change in Nannochloropsis metabolism, leading to reduced oxygen production and limiting pH changes. Taken together, this work presents a promising new type of two-chambered MFC with lower energy losses and greater power production that can also maintain a constant cathode pH and reveals a new behavior of Nannochloropsis algae in response to oxygen reduction reactions in such MFCs.

Daniele Cecconet, Arianna Callegari, Andrea Capodaglio

Energies • 2018

Groundwater contamination is a major issue for human health, due to its largely diffused exploitation for water supply. Several pollutants have been detected in groundwater; amongst them arsenic, cadmium, chromium, vanadium, and perchlorate. Various technologies have been applied for groundwater remediation, involving physical, chemical, and biological processes. Bioelectrochemical systems (BES) have emerged over the last 15 years as an alternative to conventional treatments for a wide variety of wastewater, and have been proposed as a feasible option for groundwater remediation due to the nature of the technology: the presence of two different redox environments, the use of electrodes as virtually inexhaustible electron acceptor/donor (anode and cathode, respectively), and the possibility of microbial catalysis enhance their possibility to achieve complete remediation of contaminants, even in combination. Arsenic and organic matter can be oxidized at the bioanode, while vanadium, perchlorate, chromium, and cadmium can be reduced at the cathode, which can be biotic or abiotic. Additionally, BES has been shown to produce bioenergy while performing organic contaminants removal, lowering the overall energy balance. This review examines the application of BES for groundwater remediation of arsenic, cadmium, chromium, vanadium, and perchlorate, focusing also on the perspectives of the technology in the groundwater treatment field.

Anirudh Bhanu Teja Nelabhotla, Rune Bakke, Carlos Dinamarca

Catalysts • 2019

Microbial electrosynthesis (MES) biogas upgrading is done via reduction of carbon dioxide to methane through electroactive microbial catalysis. The baseline MES mode of operation showed about a 39% increase in the methane production rate compared to the open circuit mode of operation. MES is capable of producing acetic acid at relatively more negative potential (−0.80 to –0.90 V vs. Standard Hydrogen Electrode (SHE)) than the potential at which it produces methane (−0.65 V vs. SHE). The optimum pH for enhancing the electroactive acetogens is found to be around 6.8–7.0 while a pH of around 7.0–7.5 enhances the electroactive methanogens performance. The biocathode adaptation test reveals that 45% of the methane was produced through the electrochemical pathway with a coulombic efficiency of 100% while maintaining heterotrophic efficiency above 99%.

Nuzulul Anggi Rizki, Mohammad Masykuri, Retno Rosariastuti

Journal of Biomimetics, Biomaterials and Biomedical Engineering • 2023

Ammonia is a poisonous compound that can harm fish. Fish feed and manure are the primary sources of ammonia in catfish farming ponds. High concentrations of ammonia can cause death. Therefore, it is necessary to control the presence of ammonia to minimize the potential for fish mortality. Microbial Fuel Cell (MFC) is a technology that can help with ammonia bioremediation. This study aims to analyze the effectiveness of Microbial Fuel Cell (MFC) in reducing ammonia. The research method used is an experimental research method with qualitative descriptive analysis. The research was conducted on a laboratory scale using a dual-chamber Microbial Fuel Cell (MFC) reactor connected using a salt bridge. This research was conducted with variations in the use of sticky media, including without media, with bioball, and with bioring media. The results showed that the percentage of ammonia reduction in each treatment was 94.52%, 98.09%, and 99.28%. From this research, it can be concluded that Microbial Fuel Cells (MFC) are effective in reducing ammonia.

Ardiyan Harimawan

Reaktor • 2022

As an alternative source of renewable energy that has piqued researchers’ interest, Microbial Fuel Cell’s (MFC) limitation of low power density requires further development. Various factors affect the performance, but performing all will be costly and time-consuming. Through a combination of dynamic and steady-state mathematical model modified from past research, effect of microbe types towards dynamic biofilm formation and stead-state OCV can be observed, followed by steady-state simulation to determine maximum power density and its’ corresponding voltage. Similarity with previous research has been observed, with maximum OCV of 838.93 mV achieved by heterotrophic biomass in 75-100 hours with biofilm thickness of 2.087 x 10-4 m, while generating maximum power density of 2050.12 mW//m2 and voltage of 408.16 mV. Lowest OCV value of 838.76 mV was observed in C. sporogenes in 450-475 hours with a biofilm thickness of 2.079 x 10-4 m, while the lowest value of maximum power density was observed in anaerobic microbial communities at 8.48 mW/m2 with voltage of 90.43 mV. Furthermore, it has been observed that variations with higher and lower results in higher stead-state OCV in the shortest amount of time, while increasing power density and its’ corresponding voltage. @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-536869121 1107305727 33554432 0 415 0;}@font-face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4; mso-font-charset:0; mso-generic-font-family:swiss; mso-font-pitch:variable; mso-font-signature:-469750017 -1073732485 9 0 511 0;}p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin:0cm; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:EN-US;}.MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-size:10.0pt; mso-ansi-font-size:10.0pt; mso-bidi-font-size:10.0pt; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-fareast-font-family:Calibri; mso-hansi-font-family:Calibri; mso-ansi-language:IN; mso-fareast-language:IN;}div.WordSection1 {page:WordSection1;}

Aldi Wahyuda Vestimarta, Irdawati Irdawati

MASALIQ • 2024

The current availability of electrical energy is not proportional to the large demand. This emphasizes the importance of saving electrical energy. To replace fossil fuel power plants that cannot be renewed. So Microbial Fuel Cells (MFC) is used, which is a technology that is able to convert chemical energy from organic matter into electrical energy through the process of oxidation and metabolism of anaerobic bacteria in electroactive biofilms at the anode. This study aims to determine the production of bioelectricity with Microbial Fuel Cell using consortium thermophilic bacteria on TMM substrate. This research was conducted in November 2023 in the microbiology laboratory, FMIPA, UNP. Data analysis was carried out descriptively by displaying images and graphs. Observation of the development of SSA 16 thermophilic bacteria was carried out for 24 hours by checking the voltage once every 2 hours. And the highest voltage result was 749 mv at the 10th hour of measurement.

Amanda Kusuma Dewi, Gunawan Djajakirana, Dwi Andreas Santosa

Jurnal Ilmu Tanah dan Lingkungan • 2020

Sampah organik dari industri tahu pada umumnya hanya dibuang ke aliran sungai di sekitarnya dan tidak dimanfaatkan oleh masyarakat. Limbah cair tahu mengandung banyak protein, sehingga dalam proses dekomposisi menghasilkan amonia yang menyebabkan bau. Kurangnya peneliti yang memahami bahwa limbah tahu juga dapat digunakan sebagai substrat dalam Sel Bahan Bakar Mikro (MFC). MFC adalah sistem atau perangkat yang menggunakan bakteri sebagai katalis untuk mengoksidasi bahan organik dan anorganik. Elektron diproduksi oleh bakteri dari substrat yang ditransfer ke anoda (kutub negatif) dan dialirkan ke katoda (kutub positif), kemudian dihubungkan oleh perangkat konduktivitas termasuk resistor atau dioperasikan di bawah muatan untuk menghasilkan listrik. Tujuan dari penelitian ini adalah mengetahui pengaruh penggunaan limbah tahu sebagai substrat dalam anoda terhadap arus listrik di MFC juga mengetahui pemodelan MFC paling efektif dan menyediakan listrik dengan arus tertinggi. Hasil penelitian menunjukkan bahwa pemodelan MFC yang dianggap paling efektif dan menghasilkan tegangan tertinggi adalah sistem dual chamber dengan Nafion. Ruang ganda MFC dengan isolat Nafion Staphylococcus saprophyticus mampu menghasilkan nilai tegangan 3,74x105 mV dan nilai kerapatan daya 2,87x104 mW m-2.

Álvaro Rodríguez del Río, Stefan Scheu, Matthias C. Rillig

Nature Communications • 2025

Abstract Anthropogenic activities impose multiple concurrent pressures on soils globally, but responses of soil microbes to multiple global change factors are poorly understood. Here, we apply 10 treatments (warming, drought, nitrogen deposition, salinity, heavy metal, microplastics, antibiotics, fungicides, herbicides and insecticides) individually and in combinations of 8 factors to soil samples, and monitor their bacterial and viral composition by metagenomic analysis. We recover 742 mostly unknown bacterial and 1865 viral Metagenome-Assembled Genomes (MAGs), and leverage them to describe microbial populations under different treatment conditions. The application of multiple factors selects for prokaryotic and viral communities different from any individual factor, favouring the proliferation of potentially pathogenic mycobacteria and novel phages, which apparently play a role in shaping prokaryote communities. We also build a 25 M gene catalog to show that multiple factors select for metabolically diverse, sessile and non-biofilm-forming bacteria with a high load of antibiotic resistance genes. Finally, we show that novel genes are relevant for understanding microbial response to global change. Our study indicates that multiple factors impose selective pressures on soil prokaryotes and viruses not observed at the individual factor level, and emphasizes the need of studying the effect of concurrent global change treatments.

Mohammad Javed Ali

Ophthalmic Plastic & Reconstructive Surgery • 2022

Purpose: To study the metagenome of the microbes present on the extubated lacrimal stents following a dacryocystorhinostomy. Methods: A prospective study was performed on 10 consecutive extubated lacrimal stents obtained for the metagenomic analysis from the patients following an endoscopic dacryocystorhinostomy. The stents were extubated at 4 weeks postoperatively under endoscopic guidance and immediately transported on ice to the laboratory. Following DNA extraction and library preparation, a whole shotgun metagenome sequencing was performed on the Illumina platform. The downstream processing and bioinformatics of the samples were performed using multiple software packaged in SqueezeMeta pipeline or MG-RAST pipeline. Results: The taxonomic hit distribution across the stent samples showed that bacteria were the most common isolates (mean, 69.70%), followed by viruses (mean, 0.02%) and archaea (0.003%). The 3 major phyla identified were Firmicutes, Actinobacteria, and Proteobacteria. The prevalent organisms include Pseudomonas aeruginosa, Staphylococcus aureus, Corynebacterium accolens, Dolosigranulum pigrum, Citrobacter koserii, Staphylococcus epidermidis, E. coli, and Hemophilus influenza. The functional subsystem profiling demonstrated microbial genes associated with metabolism, cellular, and information processing. The functional subsystem categories were metabolism involving carbohydrates, amino acids, DNA and RNA, cell wall or cell capsule biogenesis, membrane transport, virulence, and defense mechanisms. Conclusions: The present study is the first whole metagenome sequencing of the microbes isolated from the extubated lacrimal stents. The stents harbor diverse microbial communities with distinct ecosystem dynamics. Further studies on microbes-host interactions in the early postoperative period would provide valuable insights.

Gabriele Andrea Lugli, Marco Ventura

Microbiome Research Reports • 2022

Next-generation sequencing technologies allow accomplishing massive DNA sequencing, uncovering the microbial composition of many different ecological niches. However, the various strategies developed to profile microbiomes make it challenging to retrieve a reliable classification that is able to compare metagenomic data of different studies. Many limitations have been overcome thanks to shotgun sequencing, allowing a reliable taxonomic classification of microbial communities at the species level. Since numerous bioinformatic tools and databases have been implemented, the sequencing methodology is only the first of many choices to make for classifying metagenomic data. Here, we discuss the importance of choosing a reliable methodology to achieve consistent information in uncovering microbiomes.

TzeHau Lam, Dillon Chew, Helen Zhao et al.

Frontiers in Microbiology • 2022

Microbiomes on surfaces in kindergartens, the intermediate transfer medium for microbial exchange, can exert significant impact on the hygiene and wellbeing of young children, both individually and as a community. Here employing 2bRAD-M, a novel species-resolved metagenomics approach for low-biomass microbiomes, we surveyed over 100 samples from seven frequently contacted surfaces by children, plus individual children’s palms, in two kindergartens. Microbiome compositions, although kindergarten-specific, were grouped closely based on the type of surface within each kindergarten. Extensive microbial admixture were found among the various sampled sites, likely facilitated by contact with children’s hands. Notably, bacterial species with potential human health concerns and potentially antibiotic-resistant, although found across all sampled locations, were predominantly enriched on children’s hands instead of on the environmental sites. This first species-resolved kindergarten microbiome survey underscores the importance of good hand hygiene practices in kindergartens and provides insights into better managing hygiene levels and minimizing spread of harmful microbes in susceptible indoor environments.

Rabeay Y.A. Hassan, Ferdinando Febbraio, Silvana Andreescu

Sensors • 2021

Microbial electrochemical systems are a fast emerging technology that use microorganisms to harvest the chemical energy from bioorganic materials to produce electrical power. Due to their flexibility and the wide variety of materials that can be used as a source, these devices show promise for applications in many fields including energy, environment and sensing. Microbial electrochemical systems rely on the integration of microbial cells, bioelectrochemistry, material science and electrochemical technologies to achieve effective conversion of the chemical energy stored in organic materials into electrical power. Therefore, the interaction between microorganisms and electrodes and their operation at physiological important potentials are critical for their development. This article provides an overview of the principles and applications of microbial electrochemical systems, their development status and potential for implementation in the biosensing field. It also provides a discussion of the recent developments in the selection of electrode materials to improve electron transfer using nanomaterials along with challenges for achieving practical implementation, and examples of applications in the biosensing field.

Tanja Vidakovic-Koch

ECS Meeting Abstracts • 2023

The most popular technique for characterizing various electrochemical devices such as fuel cells, water electrolysis or batteries is electrochemical impedance spectroscopy (EIS). However, due to the coupling of dynamic phenomena with similar time constants, EIS often fails to separate the contributions of individual processes to overall performance losses. In this case, obtaining useful information from the EIS spectra can be be difficult and the interpretation of the observed patterns is unclear. In this talk, I show that new dynamical methods based on the use of nonlinearities in the system response (nonlinear frequency response analysis (NFRA) [1]), non-electrical inputs (concentration-alternating frequency response analysis (cFRA) [2]), or data-driven analyses (Loewner framework [3]) can provide additional information for understanding electrochemical conversion processes. Our current examples are related to the study of polymer electrolyte membrane electrolysis and polymer electrolyte membrane fuel cell. References [1] Vidaković-Koch T., Miličić, T., Živković, L.A., Chan, H.S., Krewer, U., Petkovska, M., (2021) Nonlinear Frequency Response Analysis: A Recent Review and Perspectives, Current Opinion in Electrochemistry, 100851. [2] Sorrentino, A., Sundmacher, K. & Vidaković-Koch, T. (2020). Polymer Electrolyte Fuel Cell Degradation Mechanisms and Their Diagnosis by Frequency Response Analysis Methods: A Review. Energies, 13(21), 5825. [3] Antoulas, A. C., Lefteriu, S., and Ionita, A. C., (2017) A tutorial introduction to the Loewner framework for model reduction in Model Reduction and Approximation, Eds: P. Benner, A Cohen, M. Ohlberger, K. Willcox, Siam Comupational Science and Engineering, Chapter 8, pp. 335–376.

Yucel KOC, Huseyin AVCİ

Eskişehir Osmangazi Üniversitesi Mühendislik ve Mimarlık Fakültesi Dergisi • 2022

ecently increasing attention has been paid to the development of highly sensitive and selective electrochemical sensors for accurate and cost-effective detection in various fields. In this study, gold nanoparticles (AuNPs) were electro-deposited onto screen printed gold electrode (SPGE) surfaces at different times to determine the optimum modification conditions. Determining the optimum modification for the SPGE surface, AuNP modification under −0.3 V potential with 2 mM HAuCl4 (in 0.5 M H2SO4) solution were investigated. In this case, for the optimum AuNP modification, electrochemical impedance spectroscopy (EIS) analysis was performed at the following deposition times: 30, 60, 90, 120, and 150 s. As a result of modeling the Nyquist graph obtained in the range of 10 kHz to 0.1 Hz with the EIS analysis based on the equivalent circuit model, the outcomes for each modification time were analyzed. After the modification with AuNPs, scanning electron microscope (SEM) images of the SPGE surfaces were discussed. As a result, the optimum deposition time was determined as 90 s by the analysis. This study can be used for electrochemical investigation and target detection in complex media in terms of AuNPs on SPGE surfaces with a detailed perspective for nanoparticle deposition.

Franz Schauer

Journal of Applied Physics • 2020

Organic electronic applications are envisioned to address broad markets, which includes flexible displays, electronic papers, sensors, disposable and wearable electronics, and medical and biophysical applications, leading to a tremendous amount of interest from both academia and industry in the study of devices. These fields of science and technology constitute interdisciplinary fields that cover physics, chemistry, biology, and materials science, leading, as a wanted output, to the elucidation of physical and chemical properties, as well as structures, fabrication, and performance evaluation of devices and the creation of new knowledge underlying the operation of organic devices using new synthesized organic materials—organic semiconductors. We testify the situation when the available organic electronic applications sometimes lack a theoretical background. The cause may be the complicated properties of disordered, weak bounded, molecular materials with properties different from their inorganic counterparts. One of the basic information-rich resources is the electronic structure of organic semiconductors, elucidated by the methods, hardly possible to be transferred from the branch of inorganic semiconductors. Electrochemical spectroscopic methods, in general, and electrochemical impedance spectroscopy, in particular, tend and seem to fill this gap. In this Perspective article, the energy resolved-electrochemical impedance spectroscopic method for electronic structure studies of surface and bulk of organic semiconductors is presented, and its theoretical and implementation background is highlighted. To show the method’s properties and strength, both as to the wide energy and excessive dynamic range, the basic measurements on polymeric materials and D–A blends are introduced, and to highlight its broad applicability, the results on polysilanes degradability, gap engineering of non-fullerene D–A blends, and electron structure spectroscopy of an inorganic nanocrystalline film are highlighted. In the outlook and perspective, the electrolyte/polymer interface will be studied in general and specifically devoted to the morphological, transport, and recombination properties of organic semiconductors and biophysical materials.

Serban Lepadatu

Journal of Applied Physics • 2020

This work discusses the design and testing of a new computational spintronics research software. Boris is a comprehensive multi-physics open-source software, combining micromagnetics modeling capabilities with drift-diffusion spin transport modeling and a heat flow solver in multi-material structures. A multi-mesh paradigm is employed, allowing modeling of complex multi-layered structures with independent discretization and arbitrary relative positioning between different computational meshes. Implemented micromagnetics models include not only ferromagnetic materials modeling, but also two-sublattice models, allowing simulations of antiferromagnetic and ferrimagnetic materials, fully integrated into the multi-mesh and multi-material design approach. High computational performance is an important design consideration in Boris, and all computational routines can be executed on graphical processing units (GPUs), in addition to central processing units. In particular, a modified 3D convolution algorithm is used to compute the demagnetizing field on the GPU, termed pipelined convolution, and benchmark comparisons with existing GPU-accelerated software Mumax3 have shown performance improvements up to twice faster.

Ravi Jenani, Arjunan Babu Ponnusami

REVIEWS ON ADVANCED MATERIALS SCIENCE • 2025

Abstract In the era of climate change and the global energy crisis, alternate energy sources are desirable to replace carbon and fossil fuels. Microbial fuel cells (MFCs) are distinctive because of their ability to transform organic waste into electricity through bio-electrochemical reactions. The current study investigates the preparation and application of zinc oxide nanoparticles (ZnO NPs) and sulfonated ZnO nanoparticles (SZnO NPs) incorporated in polyvinyl alcohol (PVA) membrane as a separator in dual-chambered MFC for Tannery wastewater treatment. Characterization of these membranes shows that the NPs are well dispersed onto the polymer base. The synthesized sulfonated membrane has better water uptake capacity (90.5%) and oxygen mass transfer coefficient (1.09 × 10−6 cm·s−1) than the Nafion membrane water uptake capacity (21.8%) and oxygen mass transfer coefficient (2.68 × 10−4 cm·s−1). Different amounts of NPs were incorporated into the polymer base to optimize the membrane performance by increasing the proton conductivity for better operation in MFC with reduced biofouling. When the MFC was operated with tannery wastewater, a maximum power density of 160.554 mW·m−2 and a chemical oxygen demand removal of 84.618% were obtained using the PVA–SZnO membrane with reduced biofouling. This observation proves that the sustainable and affordable PVA–SZnO membrane can be used as a separator for MFC and for treating Tannery wastewater.

Hongjian Lin, Sarah (Xiao) Wu, Jun Zhu

Applied Sciences • 2018

The model proposed in this study was based on the assumption that the biomass attached to the anode served as biocatalysts for microbial fuel cell (MFC) exoelectrogenesis, and this catalytic effect was quantified by the exchange current density of anode. By modifying the Freter model and combining it with the Butler–Volmer equation, this model could adequately describe the processes of electricity generation, substrate utilization, and the suspended and attached biomass concentrations, at both batch and continuous operating modes. MFC performance is affected by the operating variables such as initial substrate concentration, external resistor, influent substrate concentration, and dilution rate, and these variables were revealed to have complex interactions by data simulation. The external power generation and energy efficiency were considered as indices for MFC performance. The simulated results explained that an intermediate initial substrate concentration (about 100 mg/L under this reactor configuration) needed to be chosen to achieve maximum overall energy efficiency from substrate in the batch mode. An external resistor with the value approximately that of the internal resistance, boosted the power generation, and a resistor with several times of that of the internal resistance achieved better overall energy efficiency. At continuous mode, dilution rate significantly impacted the steady-state substrate concentration level (thus substrate removal efficiency and rate), and attached biomass could be fully developed when the influent substrate concentration was equal to or higher than 100 mg/L at any dilution rate of the tested range. Overall, this relatively simple model provided a convenient way for evaluating and optimizing the performance of MFC reactors by regulating operating parameters.

Rauno Lust, Jaak Nerut, Kuno Kasak et al.

Water • 2020

Assessments of groundwater aquifers made around the world show that in many cases, nitrate concentrations exceed the safe drinking water threshold. This study assessed how bioelectrochemical systems could be used to enhance nitrate removal from waters with low organic carbon concentrations. A two-chamber microbial electrosynthesis cell (MES) was constructed and operated for 45 days with inoculum that was taken from a municipal wastewater treatment plant. A study showed that MES can be used to enhance nitrate removal efficiency from 3.66% day−1 in a control reactor to 8.54% day−1 in the MES reactor, if a cathode is able to act as an electron donor for autotrophic denitrifying bacteria or there is reducing oxygen in a cathodic chamber to favor denitrification. In the MES, greenhouse gas emissions were also lower compared to the control. Nitrous oxide average fluxes were −639.59 and −9.15 µg N m−2 h−1 for the MES and control, respectively, and the average carbon dioxide fluxes were −5.28 and 43.80 mg C m−2 h−1, respectively. The current density correlated significantly with the dissolved oxygen concentration, indicating that it is essential to keep the dissolved oxygen concentration in the cathode chamber as low as possible, not only to suppress oxygen’s inhibiting effect on denitrification but also to achieve better power efficiency.

M. Elakkya

Advances in Nonlinear Variational Inequalities • 2025

This work describes the entrapped-cell photobioreactor Rhodopseudomonas palustris CQK 01 in a multiphase flow transport model. The model uses two relevant non-linear reaction-diffusion equations to represent the substrate and product concentrations inside the gel granules for biochemical interactions in the photobioreactor. The Akbari-Ganji and homotopy perturbation methods are used to obtain simple approximation analytical expressions for the concentrations, liquid and gas phases in the steady-state condition. The analytical and the numerical results are compared to verify the efficiency. The analytical data and the simulated results agreed well for all concentrations. Furthermore, two limiting scenarios, zero and first-order kinetics, were used, and the results were examined. The parameters in our proposed methods can be utilized to simulate the dynamic performance of a system, as evidenced by the close agreement between the simulated and analytical data.

Tamás Koncsos

Periodica Polytechnica Civil Engineering • 2020

The efficient operation of activated sludge type wastewater treatment plants is an ongoing topic for the utility providers, where electric energy consumption shares are high, giving cca. 30 % of total operational costs. Intervention methods for intensification include fine tuning of aeration settings, sludge removal and the adjustment of recirculation rates. In order to analyze the effects of various process control strategies, activated sludge models (ASM) are used for the purpose of biokinetic modeling. In practice, most model simulators do not incorporate optimization and necessary auto-calibration of the latter, due to high computational demand of timeseries evaluation. In this paper, a new mathematical model is presented, which makes biokinetic simulations suitable for the use in decision support systems. Namely, the ASM model is approximated with a computanional inexpesive quadratic model solution, fed into a set of mass-balance corrected neural networks. Cost optimization is achieved with Markov decision process model. The developed method was illustrated for a case of Hungarian, large wastewater treatment plant. It was proven, the model is able to find better aeration schemes for the plant in aspect of cost of operation and nitrogen removal efficiency. The model can be used to find cost-optimal policies under arbitrary defined conditions. As a benefit, results can be implemented into industrial logic controllers.

Weiwei Jin

Research in Health Science • 2024

In this study, the metabolic regulation mechanism of microorganisms in bioreactor was discussed, and a series of optimization strategies were proposed based on this. The key effects of metabolic regulation on the performance of bioreactors were revealed through the overview of microbial metabolic pathways and the analysis of regulatory mechanisms. In view of this, the optimization strategy based on metabolic regulation was proposed from the aspects of metabolic engineering transformation, genetic engineering technology application, metabolic pathway reconstruction and optimization. At the same time, the operating conditions of the reactor, such as temperature, pH value, dissolved oxygen, substrate concentration and mixing effect were optimized in detail. In terms of reactor design and scale-up strategy, the scale effect, reactor configuration and flow field optimization, and heat and mass transfer enhancement technology were mainly considered. This study provides important theoretical and practical guidance for the improvement of bioreactor performance and the progress of biotechnology industry.

Grace L. Baldwin, Robert M. Stwalley

Sustainability • 2022

The United Nations Food and Agriculture Organization reports approximately 1.9 million hectares (Mha) total of potential irrigatable lands in Ghana. However, the total water-managed area in the country was estimated to be only approximately 30,900 hectares (ha) in 2000 or 1.7% of the possible area. The government ultimately intends to add a total irrigatable area of 500,000 ha or more, thereby increasing the total coverage to 28% of the country’s potential. This would be beneficial because Ghana is not currently agriculturally independent and seeks to make substantial efforts in the scale-up of irrigation technologies to decrease the country’s reliance on the importation of agricultural goods. Unfortunately, the state of available technical literature for the very specific subject of agricultural water resources in a small African country is limited and generally only thinly published. A successful review of the published literature was conducted by expanding the search parameters until an adequate level of material became available to accurately describe the situation. The adaptive review process to access progressively more relevant information is presented in the methodology. The country’s total water withdrawal was quantified. The constraints on water resource development within Ghana’s socio-political environment were examined, and opportunities for technical improvement were identified. If well-managed, the country’s surface water and largely untapped groundwater systems are sufficient to meet most domestic and irrigation purposes. This analysis should provide significant aid to the government, non-governmental organizations, and aid agencies working to improve agricultural productivity via the scale-up of irrigation systems in Ghana and other similar countries.

Harriet Koorts, Harry Rutter

Health Research Policy and Systems • 2021

AbstractDespite a number of important global public health successes, for many health behaviours there is a continued lack of interventions that have been sufficiently scaled up to achieve system-wide integration. This has limited sustainable and equitable population health improvement. Systems change plays a major role in the relation between implementation processes and at-scale institutionalisation of public health interventions. However, in research, systems approaches remain underutilised in scaling up. Public health scale-up models have typically centred on intervention replication through linear expansion. In this paper, we discuss current conceptualisations and approaches used when scaling up in public health, and propose a new perspective on scaling that shifts attention away from the intervention to focus instead on achieving the desired population-level health outcomes. In our view, ‘scaling up’ exists on a continuum. At one end, effective scaling can involve a linear, intervention-orientated expansive approach that prioritises the spread of evidence-based interventions into existing systems in order to drive expansion in the application of that intervention. At the other end, we contend that scale-up can sit within a complex systems paradigm in which interventions are conceptualised as events in systems. In this case, implementation and scale-up activities should focus on generating changes within the system itself to achieve the desired outcome. This we refer to as ‘systems-orientated scale-up’ to achieving population health improvement, which can complement traditional approaches in relevant situations. We argue that for some health behaviours, our proposed approach towards scaling up could enhance intervention implementation, sustainability and population health impact.

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European Journal of Public Health • 2020

Abstract Objectives Non-communicable diseases (NCD) are a major challenge for health systems across the globe. Although effective interventions for prevention, detection and control exist, these do not reach all people in need, especially the poor and most vulnerable. Scale-up strategies are developed to increase universal access to those interventions, addressing demand-side and supply-side barriers and to facilitate integration in the health system. While there are useful frameworks to conceptualise and operationalise scale-up of NCD interventions, there is a knowledge gap on what and how to evaluate. This session addresses that knowledge gap, presenting evaluation methods for scale-up from four large multi-country research projects. The objectives are: To increase knowledge on four dimensions of scale-up evaluation: 1) contextualisation of methods; 2) implementation evaluation; 3) cost-evaluation and 4) use of health information systemsTo present methods and results of implementation research on NCDs as an example for other chronic diseasesTo illustrate how contextualisation, implementation and evaluation varies across different stages of scale-upTo stimulate learning by experience through small-group discussion with session participants This workshop provides added value through the four coherent presentations combined with small group interactions on the same topics. It allows the audience to link the case study lessons to their own research and wider application. Format Four different elements of scale-up evaluation are addressed: 1) Contextualisation of evaluation methods from a common framework; 2) Implementation evaluation at operational level; 3) Cost-evaluation of NCD interventions; and 4) Large-scale evaluation through routine health information systems (HIS). Case studies from four large-scale Horizon2020 funded research projects in 14 countries in Europe, Africa and Asia will be presented, each case focusing on one dimension. Cross-cutting themes of adaptation and transferability of methods will also be addressed. After the presentations, there will be an interactive session to promote experience-based learning in small-group discussions. Presentations Self-Management Approach and Reciprocal Learning for Type 2 Diabetes (SMART2D)Scaling-up Packages of Interventions for cardiovascular disease prevention in Europe and Sub-Saharan Africa (SPICES)Scaling-Up NCD Interventions in South-East Asia (SUNI-SEA)The Scale-Up of Diabetes and Hypertension Care (SCUBY) The presentations will provide the introduction to subsequent small-table discussions, around the following questions: How to measure and monitor implementation and outcome of intervention scale-up?How to generate transferrable lessons from cross-country studies?How to conduct cross-setting evaluation of the effect and cost of NCD interventions? Key messages The global scale-up of NCD interventions calls for robust evaluation methods of effect, implementation and cost. Evaluation methods need to be fit to the country context and health information systems.

V Buffel

European Journal of Public Health • 2020

Abstract The SCUBY project aims to (1) change the organization of primary health care for diabetes and hypertension in order to (2) improve the outcome of chronic care in three countries (Belgium-Slovenia-Cambodia). These two aims require two types of data, namely data on the organization of care and data on the chronic illness outcomes. It can however be challenging to (1) gather all these data (from various sources) on both the organization and outcomes and (2) create cross-culturally valid datasets. The presentation will present the strategy of SCUBY to gather data and discuss the issues of cross-cultural validity.

Enza Palma, Matteo Daghio, Anna Espinoza Tofalos et al.

Environmental Science: Water Research & Technology • 2018

High-rate anaerobic oxidation of toluene was achieved in a continuous-flow bioelectrochemical system.

Hang Yu, Yuhui Cao, Qingliang Zhao et al.

Frontiers in Environmental Science • 2022

A novel bioelectrochemical reactor assembled with cooperative cathodes of chemical cathode and bio-cathode (BERCC) and excess sludge as the anodic substrate obtained continuous and effective Cr(VI) reduction. Cooperative cathodes in BERCC stimulated the growth of electrochemically active microorganisms such as Geobacter sp. and Shewanella sp. in the anodic biofilm and produced 8.21 ± 0.64 mg C/(L·h) more electrons than the dual chemical cathodes in the bioelectrochemical reactor with dual chemical cathodes, which enhanced the electrons for electricity generation and Cr(VI) reduction by approximately 58.3% and 56.1 ± 5.6%, respectively.

Shelley D. Minteer

ECS Meeting Abstracts • 2019

Electrochemically interfacing bacteria with electrodes presents a dynamic new set of materials challenges. Bacteria naturally form biofilms on traditional electrode surfaces, but materials design can help promote extracellular electron transfer between the bacteria and the electrode within biofilms. This paper will discuss materials strategies for promoting biofilm formation, biofilm maintenance, and extracellular electron transfer within the film, as well as improving the lifetime of microbial bioelectrodes. We will discuss different strategies for biophotocurrent generation versus microbial fuel cells versus shock biosensors, including novel carbon materials, electrode treatments, redox polymers, and biopolymer engineering.

Qiaochu Liang, Takahiro Yamashita, Norihisa Matsuura et al.

Energies • 2019

Bioelectrochemical system (BES)-based reactors have a limited range of use, especially in aerobic conditions, because these systems usually produce current from exoelectrogenic bacteria that are strictly anaerobic. However, some mixed cultures of bacteria in aerobic reactors can form surface biofilms that may produce anaerobic conditions suitable for exoelectrogenic bacteria to thrive. In this study, we combined a BES with an aerobic trickling filter (TF) reactor for wastewater treatment and found that the BES-TF setup could produce electricity with a coulombic efficiency of up to 15% from artificial wastewater, even under aerobic conditions. The microbial communities within biofilms formed at the anodes of BES-TF reactors were investigated using high throughput 16S rRNA gene sequencing. Efficiency of reduction in chemical oxygen demand and total nitrogen content of wastewater using this system was >97%. Bacterial community analysis showed that exoelectrogenic bacteria belonging to the genera Geobacter and Desulfuromonas were dominant within the biofilm coating the anode, whereas aerobic bacteria from the family Rhodocyclaceae were abundant on the surface of the biofilm. Based on our observations, we suggest that BES-TF reactors with biofilms containing aerobic bacteria and anaerobic exoelectrogenic bacteria on the anodes can function in aerobic environments.

Geremia Sassetto, Laura Lorini, Agnese Lai et al.

Catalysts • 2024

A new membrane-less bioelectrochemical reactor configuration was developed for contaminated groundwater remediation. The new bioelectrochemical reactor configuration was inspired by the utilisation of a permeable reactive barrier (PBR) configuration with no separation membrane. The corresponding reactive zones were created by using graphite granules and mixed metal oxide (MMO) electrodes to stimulate the reductive and oxidative biological degradation of chlorinated aliphatic hydrocarbons. In the present study, the PBR-like bioelectrochemical reactor has been preliminarily operated with synthetic contaminated groundwater, testing the reductive dechlorination activity on cis-dichloroethylene (cisDCE). Moreover, to assess the effects of competing anions presence for the electron donor (i.e., the cathode), the synthetic wastewater contained sulphate and nitrate anions. In the PBR-like reactor operation, nearly all cisDCE was removed in the initial sampling port, with only VC detected as the observable RD product. During the same biotic test of the PRB reactor, the presence of both the reductive dechlorination and anions reduction was confirmed by the complete nitrate reduction in the cathodic chamber of the PRB reactor. On the contrary, sulphate reduction showed a lower activity; indeed, only 25% of the influent sulphate was removed by the PRB reactor.

Kumar Sonu, Monika Sogani, Zainab Syed et al.

Fuel Cells • 2022

AbstractThis study deals with the fabrication of a low‐cost ceramic anode made by blending the rice husk and mild steel dust with soil (RMS anode) for its application in plant microbial fuel cells (PMFCs). The high cost of electrode material has been a major concern in practical applications of the PMFC technology, but the present composition of waste materials such as rice husk, mild steel dust along with soil has served as an alternative low‐cost electrode material. Tagetes erecta plant has been used to produce clean and continuous electrical energy in the PMFC. The blending of rice husk has improved the porosity of the ceramic anode. The maximum power density recorded in PMFC with 50% rice husk anode was 1.4 mW/m2 as against 0.26 mW/m2 with the anode without rice husk. High biomass growth in terms of better plant height and higher chlorophyll content was also detected in the PMFC system within 60 working days.

Jamile Mohammadi Moradian, Songmei Wang, Amjad Ali et al.

Catalysts • 2022

Although microbial fuel cells (MFCs) have been developed over the past decade, they still have a low power production bottleneck for practical engineering due to the ineffective interfacial bioelectrochemical reaction between exoelectrogens and anode surfaces using traditional carbonaceous materials. Constructing anodes from biomass is an effective strategy to tackle the current challenges and improve the efficiency of MFCs. The advantage features of these materials come from the well-decorated aspect with an enriched functional group, the turbostratic nature, and porous structure, which is important to promote the electrocatalytic behavior of anodes in MFCs. In this review article, the three designs of biomass-derived carbon anodes based on their final products (i.e., biomass-derived nanocomposite carbons for anode surface modification, biomass-derived free-standing three-dimensional carbon anodes, and biomass-derived carbons for hybrid structured anodes) are highlighted. Next, the most frequently obtained carbon anode morphologies, characterizations, and the carbonization processes of biomass-derived MFC anodes were systematically reviewed. To conclude, the drawbacks and prospects for biomass-derived carbon anodes are suggested.

Jianzhang Li

Highlights in Science, Engineering and Technology • 2025

The use of traditional fossil fuel energy has caused serious environmental pollution problems. It is becoming increasingly urgent to find a green and clean new energy source. Microbial fuel cells (MFCs) have attracted much attention due to their renewable capabilities and green characteristics. MFCs still has certain limitations in its application process, such as its internal complexity, high cost of electrode separators and unstable power generation. Introducing different types of nanomaterials to build MFCs can solve these existing problems. However, how the introduced nanomaterials improve the electrochemical properties of MFCs remains to be further analyzed. To this end, this research will discuss the mechanism by which different regulatory strategies based on nanomaterials alter the electrochemical behavior of MFCs. Specifically, this research will focus on the impact of nanomaterials-based modification on the electrochemical performance of MFCs, including structural changes, material composite and new material preparations. The results show that the introduction of nanomaterials significantly improves the power density, current density and stability of MFCs, while enhancing catalytic activity, microbial adhesion and electron transfer efficiency. In this research, the analysis of changes in the electrochemical properties of MFCs by nanomaterials is conducive to the synthesis of novel electrochemically active nanomaterials and the development of high-performance MFCs.

E. M. Milner, E. H. Yu

Fuel Cells • 2018

AbstractMicrobial fuel cells (MFCs) are a sustainable technology for the direct conversion of biodegradable organics in wastewater into electricity. In most MFCs, the oxygen reduction reaction (ORR) is used as the cathode reduction reaction. Aerobic biocathodes, which use bacteria as biocatalysts to catalyze the cathode ORR, provide self‐sustained, robust and highly active alternatives to chemical catalysts. However, further study of the effect of oxygen mass transfer to the biofilm and cathode materials design is needed. In the current work, two aerobic biocathodes were enriched in half‐cells, and oxygen mass transfer to the biofilm and the biofilm distribution in the porous electrode structure were investigated. It was found that mass transfer of oxygen to the aerobic biocathode was a significant factor affecting cathode ORR, evidenced by a strong correlation between the air flow rate and current. Additionally, it was found that the biofilm penetrates between 20–30% into the porous carbon electrode structure, which is likely due to oxygen mass transfer limitations. The performance of a MFC with biocatalysts at both anode and cathode (64 µW cm−2 peak power at an air flowrate of 1 L min−1) showed strong correlation with air flowrate, confirming the observation in the half‐cell system.

Y.‐G. Zhao, M. Ying, Y.‐B. Fu et al.

Fuel Cells • 2019

AbstractEnhancing the electrochemical performance of anode is a critical step for improving the power output of marine benthic microbial fuel cells (BMFCs). An active anode involving the akaganeite (β‐FeOOH)‐coated carbon felt was proposed in present study. Results showed that electrochemical performance of modified anode was significantly improved. The peak current density of oxidation reaction increased from 0.664 to 6.107 A m−2. The exchange current density was improved from 11.75 × 10−3 to 151.36 × 10−3 mA cm−2. Electron transfer resistance decreased from 13.4 to 1.407 Ω, while the surface capacitance dramatically increased. The maximum power density of the BMFCs equipped with modified anode approached to 504.2 mW m−2, 2.3 times higher than that with unmodified anode. Moreover, relative abundance of dissimilatory iron reducing bacteria (DIRB) on the modified anode increased. Finally, a molecule synergetic mechanism containing electrostatic interaction and bacteria recognition between DIRB and β‐FeOOH was proposed to interpret the improvement of modified anode.

Velichkova P, Bratkova S, Angelov A et al.

Journal of Ecology & Natural Resources • 2025

Simple electron donors (such as lactate, ethanol, glucose, etc.) in the process of microbial sulfate reduction are well studied. In search of new substrates for sulfate-reducing bacteria, multicomponent organic products were investigated. The application of distillery wastewater (vinasse and ethanol stillage) as electron donors in a microbial sulfate reduction process with an integrated microbial fuel cell was studied. The results were compared with those of lactate as a control. The influence of the rate of volumetric sulfate loading on the rate of microbial processes was studied using six different hydraulic retention times: 14, 18, 22, 26, 30 and 34 hours. During the process, sulfate-reducing bacteria incompletely oxidize organic matter in the used distillery wastewater and generate large amounts of acetic acid, and propionic acids as a product of other microbiological processes. The rates of sulfate and organic removal for all three substrates increase with increasing retention time. In the case of vinasse and stillage at the 34th hour, sulfate removal was 98%, and organics removal was 48 and 44%, respectively. The open circuit voltage values for both fuel cells with wastewaters were highest at the 22nd hour. The results showed that vinasse and ethanol stillage were suitable electron donors in the process of microbial sulfate reduction and the resulting metabolites can be a substrate for other anaerobic processes.

Youssef A. Youssef, Mohamed E. Abuarab, Ahmed Mahrous et al.

RSC Advances • 2023

Coupling CWs with MFCs enhanced ibuprofen removal. Eichhornia crassipes remarkably contributed to ibuprofen removal. CW-MFC represents a technically and economically feasible option for pharmaceutical wastewater treatment and electricity production.