Search Results (437)

Microbial fuel cells (MFCs) are bio-electrochemical systems that harness microorganisms to convert organic pollutants in wastewater directly into electricity, offering a dual solution for sustainable wastewater treatment and renewable energy generation. This paper presents a holistic techno-economic and environmental feasibility assessment of large-scale MFC deployment in Dhaka’s industrial zone, Bangladesh, as a relevant case study. Here, treating 100,000 cubic meters of wastewater daily would require a capital investment of approximately USD 500 million, with a total project cost ranging between USD 307.38 million and 1.711 billion, depending on system configurations. This setup has an estimated theoretical energy recovery of 478.4 MWh/day and a realistic output of 382 MWh/day, translating to a per-unit energy cost of USD 0.2–1/kWh. MFCs show great potential for treating wastewater and addressing energy challenges. However, this paper explores remaining challenges, including high capital costs, electrode and membrane inefficiencies, and scalability issues. Full article

This study focuses on electrical stimulation for composting. Using the PSALSAR method, a comprehensive systematic review analysis identified 22 relevant articles. The examined studies fall into four main systems: electric field-assisted aerobic composting (EAAC), electrolytic oxygen aerobic composting (EOAC), microbial fuel cells (MFCs), and thermoelectric generators (TEGs). Apart from the main systems highlighted above, bioelectrochemically assisted anaerobic composting (AnC_{BE, III}) is discussed as an underexplored system with the potential to improve the efficiency of anaerobic degradation. Each system is described in terms of key materials, composter design, operating conditions, temperature evolution, compost maturity, microbial community, and environmental outcomes. EAAC and EOAC systems accelerate organic matter decomposition by improving oxygen distribution and microbial activity, whereas MFC and TEG systems have dual functioning due to the energy generated alongside waste degradation. These innovative systems not only significantly improve composting efficiency by speeding up organic matter breakdown and increasing oxygen supply but also support sustainable waste management by reducing greenhouse gas emissions and generating bioelectricity or heat. Together, these systems overcome the drawbacks of conventional composting systems and promote future environmental sustainability solutions. Full article

This study introduces an advanced strategy for improving microbial fuel cell (MFC) performance in hexavalent chromium (Cr(VI)) wastewater treatment. A high-performance nano-iron sulfide (nano-FeS) hybridized biocathode was developed by regulating glucose concentration and applying an external voltage. The combination of a glucose concentration of 1000 mg/L and a 0.2 V applied voltage greatly promoted the in situ biosynthesis of nano-FeS, resulting in smaller particle sizes and increased quantities within the biocathode, leading to enhanced electrochemical performance. The MFC with the hybridized biocathode exhibited the highest power density (43.45 ± 1.69 mW/m²) and Cr(VI) removal rate (3.99 ± 0.09 mg/L·h), outperforming the control by 29% and 71%, respectively. The improvements were attributed to the following processes. (1) Nano-FeS provided additional active sites that enhanced electron transfer and electrocatalytic activity, reducing cathode passivation; (2) it protected microorganisms by reducing Cr(VI) toxicity, promoting redox-active substance enrichment and antioxidant enzyme secretion, which maintained microbial activity; (3) the biocathode selectively enriched electroactive and Cr(VI)-reducing bacteria (such as Brucella), fostering a stable and symbiotic microbial community. This study highlights the promising potential of regulating carbon source and external voltage to boost nano-FeS biosynthesis, offering a sustainable and efficient strategy for MFC-based Cr(VI) wastewater treatment with practical implications. Full article

This study systematically compares the environmental and economic performance of three wastewater treatment systems: constructed wetlands (CWs), microbial fuel cells (MFCs), and their integration (CW–MFC). Lab-scale units of each system were constructed using a multi-media matrix (gravel, zeolite, and granular activated carbon), composite native wetland species (Juncus effusus, Iris sp., and Typha angustifolia), carbon-based electrodes (graphite), and standard inoculum for CW and CW–MFC. The MFC system employed carbon-based electrodes and proton-exchange membrane. The experimental design included a parallel operation of all systems treating domestic wastewater under identical hydraulic and organic loading rates. Environmental impacts were quantified across construction and operational phases using life cycle assessment (LCA) with GaBi software 9.2, employing TRACI 2021 and ReCiPe 2016 methods, while techno-economic analysis (TEA) evaluated capital and operational costs. The key results indicate that CW demonstrates the lowest global warming potential (142.26 kg CO₂-eq) due to its reliance on natural biological processes. The integrated CW–MFC system achieved enhanced pollutant removal (82.8%, 87.13%, 78.13%, and 90.3% for COD, NO₃, TN, and TP) and bioenergy generation of 2.68 kWh, balancing environmental benefits with superior treatment efficiency. In contrast, the stand-alone MFC shows higher environmental burdens, primarily due to energy-intensive material requirements and fabrication processes. TEA results highlight CW as the most cost-effective solution (USD 627/m³), with CW–MFC emerging as a competitive alternative when considering environmental benefits and operational efficiencies (USD 718/m³). This study highlights the potential of hybrid systems, such as CW–MFC, to advance sustainable wastewater treatment technologies by minimizing environmental impacts and enhancing resource recovery, supporting their broader adoption in future water management strategies. Future research should focus on optimizing materials and energy use to improve scalability and feasibility. Full article

Microbial Fuel Cell (MFC) is a novel bioelectrochemical system that catalyzes the oxidation of chemical energy in organic waste and converts it directly into electrical energy through the attachment and growth of electroactive microorganisms on the electrode surface. This technology realizes the synergistic effect of waste treatment and renewable energy production. A CF-NiO-PANI capacitor composite anode was prepared by loading polyaniline on a CF-NiO electrode to improve the capacitance of a CF electrode. The electrochemical characteristics of the composite anode were evaluated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), and the electrode materials were analyzed comprehensively by scanning electron microscopy (SEM), energy diffusion spectrometer (EDS), and Fourier transform infrared spectroscopy (FTIR). MFC system based on CF-NiO-PANI composite anode showed excellent energy conversion efficiency in potato starch wastewater treatment, and its maximum power density increased to 0.4 W/m³, which was 300% higher than that of the traditional CF anode. In the standard charge–discharge test (C1000/D1000), the charge storage capacity of the composite anode reached 2607.06 C/m², which was higher than that of the CF anode (348.77 C/m²). Microbial community analysis revealed that the CF-NiO-PANI anode surface formed a highly efficient electroactive biofilm dominated by electrogenic bacteria (accounting for 47.01%), confirming its excellent electron transfer ability. The development of this innovative capacitance-catalytic dual-function anode material provides a new technical path for the synergistic optimization of wastewater treatment and energy recovery in MFC systems. Full article

Microbial fuel cells (MFCs) generate electricity through the microbial oxidation of organic waste. However, the inherent electrochemical performance of carbon felt (CF) electrodes is relatively poor and requires enhancement. In this study, nickel oxide (NiO) was successfully loaded onto CF to improve its electrode performance, thereby enhancing the electricity generation capacity of MFCs during the degradation of treated wastewater. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy diffusion spectrometer (EDS) analyses confirmed the successful deposition of NiO on the CF surface. The modification enhanced both the conductivity and capacitance of the electrode and increased the number of microbial attachment sites on the carbon fiber filaments. The prepared CF–NiO electrode was employed as the anode in an MFC, and its electrochemical and energy storage performance were evaluated. The maximum power density of the MFC with the CF–NiO anode reached 0.22 W/m², compared to 0.08 W/m² for the unmodified CF anode. Under the C1000-D1000 condition, the charge storage capacity and total charge output of the CF–NiO anode were 1290.03 C/m² and 14,150.03 C/m², respectively, which are significantly higher than the 452.9 C/m² and 6742.67 C/m² observed for the CF anode. These results indicate notable improvements in both power generation and energy storage performance. High-throughput gene sequencing of the anodic biofilm following MFC acclimation revealed that the CF–NiO anode surface hosted a higher proportion of electroactive bacteria. This suggests that the NiO modification enhances the biodegradation of organic matter and improves electricity generation efficiency. Full article

Microbial electrochemical technologies (METs), such as microbial fuel cells (MFCs) and microbial electrolysis cells (MECs), show promise for sustainable energy generation from biomass waste and wastewater. However, further work is necessary for their practical use. In particular, it has been argued that process performances, such as those for organics removal and energy generation, should be substantially improved to catch up with those of existing processes, such as anaerobic digesters. Recent work has reported that bioaugmentation (BA) with electroactive microbes (EAMs) can significantly improve the performance of MFCs and MECs, while previous reports have also documented BA cases with limited impacts. In this article, after summarizing EAMs that have been isolated and characterized as possible BA agents, we comparatively analyze past BA trials for MET processes. Based on the information thus obtained, key factors that should be considered for successful BA are suggested. Full article

Plastic pollution remains a critical global environmental challenge, with conventional disposal methods contributing to ecosystem degradation. Simultaneously, energy scarcity affects numerous rural communities, limiting development opportunities. This study presents an innovative approach that integrates microbial fuel cells (MFCs) with Klebsiella oxytoca to simultaneously degrade plastic waste and generate bioelectricity. The monitoring results over 40 days revealed optimal performance on day 28, with a peak voltage of 0.714 ± 0.026 V and an electric current of 3.149 ± 0.124 mA. The biocatalyst exhibited an electrical conductivity of 140.466 ± 5.180 mS/cm and an oxidation-reduction potential of 109.519 ± 5.35 mV, indicating efficient electron transfer. Furthermore, the MFCs achieved a maximum power density of 11.391 ± 0.814 mW/cm² with a current density of 5.106 mA/cm², demonstrating their potential for sustainable energy production. Fourier transform infrared (FTIR) analysis confirmed structural modifications in the plastic, with decreased vibrational peaks indicative of polymer degradation. Additionally, scanning electron microscopy (SEM) micrographs revealed porosity and surface cracks, highlighting Klebsiella oxytoca’s biodegradation capacity. These findings establish the viability of bioelectrochemical systems for simultaneous waste remediation and renewable energy generation, paving the way for scalable applications in environmental biotechnology. By coupling microbial degradation with electricity production, this research supports the development of sustainable solutions aligned with the principles of circular economy and climate change mitigation. Full article

The projected global energy demand for 2050 drives the imperative search for alternative and environmentally friendly energy sources. An emerging and promising alternative is microbial fuel cells assisted with microalgae. This research evaluated the potential of Chlorella sp. biomass in electricity production using microbial fuel cells (MFCs) with a single chamber and activated carbon and zinc electrodes at the laboratory scale over 20 days of operation. Maximum values of voltage (1271 ± 2.52 mV), current (4.77 ± 0.02 mA), power density (247.514 mW/cm²), current density (0.551 mA/cm²), and internal resistance (200.83 ± 0.327 Ω) were obtained. The biomass-maintained pH values of 7.32 ± 0.03–7.74 ± 0.02 and peaks of electrical conductivity of 2450 ± 17.1 µS/cm and oxidation-reduction potential of 952 ± 20 mV were reached. Meanwhile, cell density and absorbance increased to average values of 2.2933 × 10⁷ ± 1.15 × 10⁶ cells/mL and 3.471 ± 0.195 absorbance units (AU), respectively. Scanning electron microscopy micrographs allowed the observation of filamentous structures of the formed biofilm attached to carbon particles, and energy-dispersive X-ray spectroscopy spectra of the anodes determined the predominance of oxygen, carbon, silicon, aluminum, and iron. Finally, this research demonstrates the great potential of Chlorella sp. biomass for sustainable bioelectricity generation in MFCs. Full article

The xeno-fungusphere, a novel microbial ecosystem formed by integrating exogenous fungi, indigenous soil microbiota, and electroactive microorganisms within microbial fuel cells (MFCs), offers a transformative approach for agricultural remediation and medicinal plant conservation. By leveraging fungal enzymatic versatility (e.g., laccases, cytochrome P450s) and conductive hyphae, this system achieves dual benefits. First, it enables efficient degradation of recalcitrant agrochemicals, such as haloxyfop-P, with a removal efficiency of 97.9% (vs. 72.4% by fungi alone) and a 27.6% reduction in activation energy. This is driven by a bioelectric field (0.2–0.5 V/cm), which enhances enzymatic activity and accelerates electron transfer. Second, it generates bioelectricity, up to 9.3 μW/cm², demonstrating real-world applicability. In medicinal plant soils, xeno-fungusphere MFCs restore soil health by stabilizing the pH, enriching dehydrogenase activity, and promoting nutrient cycling, thereby mitigating agrochemical-induced inhibition of secondary metabolite synthesis (e.g., ginsenosides, taxol). Field trials show 97.9% herbicide removal in 60 days, outperforming conventional methods. Innovations, such as adaptive electrodes, engineered strains, and phytoremediation-integrated systems, have been used to address soil and fungal limitations. This technology bridges sustainable agriculture and bioenergy recovery, offering the dual benefits of soil detoxification and enhanced crop quality. Future IoT-enabled monitoring and circular economy integration promise scalable, precision-based applications for global agroecological resilience. Full article

Volatile organic compounds (VOC) are major contributors to the burgeoning air pollution issue, predominantly from industrial areas, with well-documented environmental and health risks, which demand efficient and sustainable control policies. This review analyzes the current technological challenges and investigates recent developments in biological treatment technologies for VOC-contaminated off-gases, including biofilters, biotrickling filters, and bioscrubber, as well as emerging technologies, such as bioaugmentation and microbial fuel cells (MFCs). Operational performance, economic feasibility, and adaptability to various industrial applications are assessed, alongside opportunities for integration with other technologies, including energy recovery technologies. Biological systems offer considerable advantages regarding cost savings and lower environmental impacts and enhanced operational flexibility, particularly when combined with innovative materials and microbial optimization techniques. Nevertheless, challenges persist, such as choosing the best treatment settings suited to different VOC streams and addressing biofilm control concerns and scalability. Overall, biological VOC treatments are encouraging sustainable solutions, though continued research into reactor design, microbial dynamics, and MFC-based energetic valorization is essential for broader industrial application. These insights cover advancements and highlight the continuous need for innovative prowess to forge sustainable VOC pollution control. Full article

A novel three-dimensional porous biocarbon electrode with exceptional biocompatibility was synthesized via a facile approach using pumpkin as the precursor. The obtained pumpkin-derived biocarbon features a highly porous architecture and serves as an efficient biocarbon electrode (denoted as PBE) in a microbial fuel cell (MFC). This PBE could form robust biofilms to facilitate the adhesion of electroactive bacteria. When used in the treatment of real wastewater, the assembled PBE-MFC achieves a remarkable power density of 231 mW/m², much higher than the control (carbon brush—MFC, 164 mW/m²) under the identical conditions. This result may be attributed to the upregulation of flagellar assembly pathways and bacterial secretion systems in the electroactive bacteria (e.g., Hydrogenophaga, Desulfovibrio, Thiobacillus, Rhodanobacter) at the anode of the PBE-MFC. The increased abundance of nitrifying bacteria (e.g., Hyphomicrobium, Sulfurimonas, Aequorivita) and organic matter-degrading bacteria (e.g., Lysobacter) in the PBE-MFC also contributed to its exceptional wastewater treatment efficiency. With its outstanding biocompatibility, cost-effectiveness, environmental sustainability, and ease of fabrication, the PBE-MFC displays great potential for application in the field of high-performance and economic wastewater treatment. Full article

Corn is one of the most widely produced cereals worldwide, generating large amounts of waste, represents an environmental and economic challenge. In regions such as Africa and rural areas of Peru, access to electricity is limited, affecting quality of life and economic development. This study proposes using microbial fuel cells (MFCs) to convert chicha de jora waste—a traditional fermented beverage made from corn—into electrical energy. Single-chamber MFCs with activated carbon (anode) and zinc (cathode) electrodes were used. A total of 100 ml of chicha de jora waste was added in each MFC, and three MFCs were used in total. The MFCs demonstrated the viability of chicha de jora waste as a substrate for bioelectricity generation. Key findings include a notable peak in voltage (0.833 ± 0.041 V) and current (2.794 ± 0.241 mA) on day 14, with a maximum power density of 5.651 ± 0.817 mW/cm². The pH increased from 3.689 ± 0.001 to 5.407 ± 0.071, indicating microorganisms’ degradation of organic acids. Electrical conductivity rose from 43.647 ± 1.025 mS/cm to 186.474 ± 6.517 mS/cm, suggesting ion release due to microbial activity. Chemical oxygen demand (COD) decreased from 957.32 ± 5.18 mg/L to 251.62 ± 61.15 mg/L by day 18, showing efficient degradation of organic matter. Oxidation-reduction potential (ORP) increased, reaching a maximum of 115.891 ± 4.918 mV on day 14, indicating more oxidizing conditions due to electrogenic microbial activity. Metagenomic analysis revealed Bacteroidota (48.47%) and Proteobacteria (29.83%) as the predominant phyla. This research demonstrates the potential of chicha de jora waste for bioelectricity generation in MFCs, offering a sustainable method for waste management and renewable energy production. Implementing MFC technology can reduce environmental pollution caused by corn waste and provide alternative energy sources for regions with limited access to electricity. Full article

The intensification of agricultural production due to high global demand has led to uncontrolled waste production from this industry, creating an environmental imbalance due to inadequate waste management. In developing regions, the lack of access to electricity has become a critical problem, affecting people’s health, education, and economy. To address this issue, alternative and sustainable ways of generating electricity have been explored. This research focuses on the potential of using asparagus waste in single-chamber microbial fuel cells (MFCs) at different pH levels (4, 4.7—target, 7, and 9) to achieve optimal performance. It has been demonstrated that using this substrate, the MFC at pH 7 obtained the best results on the seventh day, generating an electric current of 4.859 mA and a maximum voltage of 0.965 V. The substrate showed an oxidation-reduction potential of 312.821 mV, a chemical oxygen demand reduction of 76.47%, and an electrical conductivity of 254.854 mS/cm. Additionally, it managed to generate a power density of 2.149 mW/cm² at a current density of 5.979 mA/cm². MFCs at different pH levels (4, 4.7—target, 7, and 9) demonstrated their potential to generate electrical energy by powering an LED light when connected in series. This research holds promise in promoting sustainable energy solutions for the future. Full article

The extensive use of antibiotics as essential medications in contemporary healthcare has resulted in significant amounts of these drugs entering the environment, both in original and metabolic forms, which presents serious ecological and health hazards. This paper examines the natural processes that break down antibiotics in water, including photolysis, hydrolysis, and biodegradation. It also discusses advancements in artificial degradation technologies, such as advanced oxidation processes (AOPs), physicochemical methods, ionizing radiation degradation, artificial wetland technology, microalgae technology, microbial electrochemical systems, and innovative catalysts. While current technologies demonstrate promising potential for use, they encounter challenges related to the catalyst stability, cost, and ecological safety. Future research should focus on optimizing degradation methods and creating efficient, sustainable multi-technology systems, such as the photocatalysis–membrane filtration coupling system; the ultrasound–Fenton–artificial wetland synergistic system; the electrochemical–biodegradation combined system; and the microbial fuel cell (MFC)–photocatalysis synergistic system, to tackle the complexities of antibiotic pollution in the environment. Full article