单室微生物燃料电池产电特性研究

采用石墨板为阴极构建了单室空气阴极微生物燃料电池(MFC),以混合菌种接种,并以乙酸钠和碳酸氢钠为碳源,研究了该MFC在间歇运行条件下的产电性能、电池内阻情况和COD去除率。结果表明,最高输出电压随着周期数增加而增加,由0.075 9 V上升到0.200 6 V,最大输出功率密度为34.80 mW/m2;在一个运行周期内,电池内阻随着时间的延长而逐渐增大,由376.6Ω上升到682.0Ω,电池内阻的增大将导致输出电压降低。COD去除率由起始的49.23%达到最大值86.99%,说明此单室空气阴极微生物燃料电池在产电的同时处理污水的效果也较好。     

石墨束微生物燃料电池产电性能研究

试验研究了以乙酸钠为燃料,以石墨束为阳极的双室微生物燃料电池的产电情况.试验结果表明,经过6d的启动期,电池输出电压达到稳定状态,以乙酸钠为燃料时最大输出电压可达到698mV,并可持续10d左右,电池内阻为44.6Ω,最大体积功率密度可达6 321.1 mW/m3,最大面积功率密度为745.5 mW/m2,COD的去除率可达85%以上.燃料电池在外阻为510Ω条件下运行1个周期,其库仑效率约为20%.     

阴极电子受体对微生物燃料电池性能的影响

以双室型微生物燃料电池为试验装置,比较铁氰化钾、重铬酸钾、高锰酸钾作为阴极电子受体时微生物燃料电池的电压和功率输出。结果表明,高锰酸钾与重铬酸钾混合电子受体对微生物燃料电池性能的提高没有显著效果,不如两者的单独表现;高锰酸钾对应的最高输出电压可达1 160 mV,但很不稳定,会很快下降到600 mV左右,在实际应用中有一定障碍;在酸性条件(pH=3.0)下,重铬酸钾的开路电压为1 081.2 mV,最大输出功率密度为35.1 W/m3,电池内阻为170.27Ω,而且表现稳定,是理想的阴极电子受体。     

单室空气阴极微生物燃料电池处理模拟生活废水同步产电研究

以某生活污水处理站厌氧池活性污泥为混合菌种,以葡萄糖为模拟生活废水,构建单室微生物燃料电池.利用微生物燃料电池实验生活废水降解与同步产电.实验结果表明:当葡萄糖浓度控制10mmol·L-1,pH值为7,温度控制在35℃时,其输出电压最大为0.486V,COD去除率最高为46.11％.微生物燃料电池(MFC)具有最佳的电化学性能.     

集胞藻PCC-6803催化的光合微生物燃料电池性能研究

以集胞藻PCC-6803(Synechocystis PCC-6803)为阳极催化剂搭建直接利用太阳能的双室H-型光合微生物燃料电池(PMFC),通过极化曲线法、交流阻抗法、循环伏安法等电化学方法,开展电极面积比、质子交换膜、内阻等因素对光合微生物燃料电池产电的影响研究。试验结果显示:在PMFC运转过程中,其输出功率稳定,且达到的最大功率密度为72.3 mW/m2;阴阳极面积大小对PMFC产电性能没有显著影响,说明双室光合微生物燃料电池中,质子交换膜传递质子的速率较慢,限制了PMFC发电效能的提高。PMFC启动后,随着生物膜的增长,其欧姆内阻、极化内阻、总内阻都呈现下降的趋势,且欧姆内阻下降的速率小于极化内阻,从而使欧姆内阻占总内阻的比率变大,进一步说明质子交换膜传递质子的速率是限制PMFC发电的关键因素。     

基于TPS61200的微生物燃料电池能量回收系统

以体积分别为8 L和4.5 L的单室空气阴极微生物燃料电池(MFC)为组件,构建宽式堆栈(WMFC)和窄式堆栈(NMFC)两种MFC堆栈,以乙酸钠为基质对比了不同运行阶段下两种堆栈串并联条件下的性能情况。在启动后60天,并联WMFC的最大功率密度(P_max)为49.06 W/m³,并联NMFC的P_max为53.12 W/m³,性能均优于串联连接方式。随后以并联方式构建两种体积均为40 L的堆栈,通过接入自主设计的储能电路定量考察不同堆栈的能量收集情况,完整运行2个周期后,宽式堆栈可将电池电量充至100%,窄式堆栈可将电量充至83%。优选后最终形成以宽式堆栈为主要放大电池工艺构型的MFC堆栈运行方案。     

微生物燃料电池数学模型的建立与仿真分析

微生物燃料电池(Microbial Fuel Cell,MFC)是燃料电池中特殊的一类,它能在微生物的作用下将化学能转化为电能,实现污水处理和产电的双重效果。目前对于MFC的研究多处于实验阶段,由于MFC内部极其复杂,从实验角度准确研究其内部各种现象以及分析运行参数对MFC的影响具有相当大的难度。文章通过集成的生化反应,在Bultler-Volmer表达式以及质量/电荷平衡的基础上,在MATLAB仿真平台下建立了双室MFC系统的数学模型并对其进行仿真分析,具有极大的理论指导意义。     

乳制品废水作为微生物燃料电池底物的研究

用乳制品废水作为阳极室底物构建双室MFC反应器,厌氧池污泥混合菌作为生物催化剂,阴极室分别使用不同浓度的KMnO4溶液和溶解氧DO作为电子受体,调节MFC影响因子与该厌氧池对应,计算试验数据并与厌氧池废水处理效果进行比较,同时观察MFC的产电性能。结果表明:双室MFC的产电效率和稳定性随着阴极室KMnO4浓度的升高而提高;当溶解氧DO作为电子受体时,MFC产电性能较低,具有成本低、无污染的优点;经不同组MFC分别处理乳制品废水后,COD去除率均优于普通厌氧池的处理效果。     

微生物燃料电池的反应动力学研究

微生物燃料电池的理论基础包括热力学、反应动力学和酶动力学3个方面。从反应动力学方面分析,微生物燃料电池中,葡萄糖在阳极的电化学反应是异相的,只能发生在阳极电极和阳极溶液的交界处。微生物燃料电池的电压损失包括活化损失、欧姆损失和浓度损失。活化损失可通过降低溶液温度和提高交换电流密度的方法减小。欧姆损失可通过采用高电导率的阳极溶液和阴极溶液、减小电极之间的距离和增大反应器截面面积的方法减小。浓度损失可通过采用降低溶液温度和增大极限电流密度的方法减小。     

以模拟有机废水为基质的单池微生物燃料电池的产电性能

利用自制单池微生物燃料电池,以破碎厌氧颗粒污泥上清液接种,以葡萄糖模拟废水为基质,成功获得了电能。含有质子交换膜的微生物燃料电池经过206h的连续运行,最高功率密度达到了141.5mW/m2,库仑效率最大为6.9%;不含质子交换膜的微生物燃料电池具有更好的产电能力,其最高功率密度为269mW/m2,库仑效率为6.6%;扫描电镜观察发现,阳极表面的产电细菌以一种短杆菌为主,在质子交换膜表面的细菌则以椭球菌为主。     

Ammonia inhibition of electricity generation in single-chambered microbial fuel cells

Batch experiments are conducted at various concentrations of initial total ammonia nitrogen (TAN) with acetate as an electron donor to examine the effects of free ammonia (NH₃) inhibition on electricity production in single-chambered microbial fuel cells (MFCs). This research demonstrates that initial TAN concentrations of over 500 mg N L⁻¹ significantly inhibit electricity generation in MFCs. The maximum power density of 4240 mW m⁻³ at 500 mg N L⁻¹ drastically decreases to 1700 mW m⁻³ as the initial TAN increases up to 4000 mg N L⁻¹. Nitrite and nitrate analysis confirms that nitrification after complete acetate removal consumes some TAN. Ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) are also inhibited by increasing the initial TAN concentrations. Another batch experiment verifies the strong inhibitory effect of TAN with only small differences between the half-maximum effective concentration (EC₅₀) for TAN (894 mg N L⁻¹ equivalent to 10 mg N L⁻¹ as NH₃) and optimum TAN conditions; it requires careful monitoring of the TAN for MFCs. In addition, abiotic control experiments reveal that granular activated carbon, which is used as an auxiliary anode material, adsorbs a significant amount of ammonia at each TAN concentration in batch MFCs.     

MFCs处理养猪场废水及其产电性能的中试研究

文章开展了微生物燃料电池(Microbial Fuel Cells,MFCs)处理养猪场废水的中试研究。试验装置有效容积为305 L,设计水力停留时间(HRT)为24 h,考察该装置对养猪场废水的处理效果及其产电能力。结果表明:当反应器稳定运行后,出水COD保持在500 mg/L以下,出水恶臭明显减少;出水重金属全部指标均达到农田灌溉水质标准,但出水氨氮与总磷去除效果较差;外接1Ω电阻时,输出电压保持在400 mV以上,最大功率密度达到154.9 mW/m~2。     

Effects of furan derivatives and phenolic compounds on electricity generation in microbial fuel cells

Lignocellulosic biomass is an attractive fuel source for MFCs due to its renewable nature and ready availability. Furan derivatives and phenolic compounds could be potentially formed during the pre-treatment process of lignocellulosic biomass. In this study, voltage generation from these compounds and the effects of these compounds on voltage generation from glucose in air-cathode microbial fuel cells (MFCs) were examined. Except for 5-hydroxymethyl furfural (5-HMF), all the other compounds tested were unable to be utilized directly for electricity production in MFCs in the absence of other electron donors. One furan derivate, 5-HMF and two phenolic compounds, trans-cinnamic acid and 3,5-dimethoxy-4-hydroxy-cinnamic acid did not affect electricity generation from glucose at a concentration up to 10 mM. Four phenolic compounds, including syringaldeyhde, vanillin, trans-4-hydroxy-3-methoxy, and 4-hydroxy cinnamic acids inhibited electricity generation at concentrations above 5 mM. Other compounds, including 2-furaldehyde, benzyl alcohol and acetophenone, inhibited the electricity generation even at concentrations less than 0.2 mM. This study suggests that effective electricity generation from the hydrolysates of lignocellulosic biomass in MFCs may require the employment of the hydrolysis methods with low furan derivatives and phenolic compounds production, or the removal of some strong inhibitors prior to the MFC operation, or the improvement of bacterial tolerance against these compounds through the enrichment of new bacterial cultures or genetic modification of the bacterial strains.     

Improve 3D electrode materials performance on electricity generation from livestock wastewater in microbial fuel cell

Swine wastewater that is collected from animal husbandry has organic high ammonia nitrogen. In this study, swine wastewater is converted into electrical energy using microbial fuel cells (MFCs). Carbon fibers are respectively combined with zinc-coated metallic wires or stainless steel wires in order to form different laminated electrodes, whose influence on the electricity generation of MFCs is then examined. The 3D laminated FN/carbon composites are used as electrodes, the stable electricity voltage is 291 mV and the COD removal efficiency reaches 81％. In contrast, SS/carbon composites only contribute to a stable electricity voltage of 12.3 mV and COD removal efficiency of 33%. Based on the surface contact angle test and the scanning electron microscopy (SEM) observation, the laminated FN/carbon composites have greater hydrophilicity and wettability than the laminated SS/carbon composites, and thus have a positive influence on the electricity generation of MFCs.     

Increased microbial fuel cell performance using quaternized poly ether ether ketone anionic membrane electrolyte for electricity generation

A high-performance hydroxide exchange membrane was prepared by the chloromethylation and quaternization of Poly ether ether ketone (PEEK) for microbial fuel cell applications. The study reports on the synthesis of a novel quaternized poly ether ether ketone (QPEEK) membrane and subsequent utilization of the ionomer as an anion exchange membrane (AEM). The structural characterization of chloromethylation and quaternization of PEEK was confirmed by FT-IR and ₁H¹ NMR spectroscopy and the morphologies were viewed by scanning electron microscopy. The effects of oxygen crossover and specific substrate crossover on cathode potential were also studied in detail. The investigation of QPEEK with the commercially available AEM (AMI-7001) revealed that the QPEEK shows excellent static properties, i.e. ion-exchange capacity, water uptake, thickness, etc.; and kinetic properties, i.e. diffusion permeability and better durability over 250 days. Power density obtained from an MFC containing the QPEEK-AEM produced higher value (60 W/m³) than the commercial AMI-7001 AEM (52 W/m³). This study shows that QPEEK could be used as an efficient and a cost effective AEM for an MFC.     

In situ Fenton-enhanced cathodic reaction for sustainable increased electricity generation in microbial fuel cells

This study reports that Fenton's reaction is capable of facilitating cathodic reaction and thus increasing the current output in microbial fuel cells (MFCs). The hydroxyl radicals (OH) produced via Fenton's reaction are demonstrated to be vital to the enhancement of electricity generation in MFCs. In a two-chamber MFC employing expanded polytetrafluoroethylene (e-PTFE) laminated cloth as a separator, the power output is enhanced approximately four times with Fenton's reaction. However, the enhancement lasts only a short time period due to the rapid consumption of Fenton's reagents. To overcome this problem, a Fe@Fe₂O₃/carbon felt (CF) composite cathode is made, which results in a greater and, more importantly, sustainable power output. In the composite cathode, Fe@Fe₂O₃ functions as a controllably releasing Fenton iron reagent and CF functions as an air-fed cathode to electro-generate H₂O₂. This newly developed MFC with a Fenton system can ensure a continuous high power output, and also provides a potential solution to the simultaneous electricity generation and degradation of recalcitrant contaminants.     

Effects of magnetic fields on electricity generation in a photosynthetic ceramic microbial fuel cell

The aim of this study was to improve the efficiency of traditional proton exchange membranes by replacement using ceramic membranes with microalgae cathodes under various magnetic fields (MFs) of 100–300 mT in a ceramic microbial fuel cell (CMFC). The experimental results showed that the power generation can be enhanced by 61% when implementing a 200 mT MF. The application of a higher MF intensity, up to 200 mT, increased the electric charge generation yet decreased it with a higher MF value. Additionally, the MF had the ability to improve the power density of the CMFC, and a maximum power density of 35.9 mW m^?2 and maximum current density of 158.7 mA m^?2 were achieved with the 200 mT MF. Moreover, biocathode maintains a stable pH value that obtained more microalgae biomass by 200 mT MF stimulation. Further work will be focused on optimizing the appropriate MF intensity along with the capacity of carbon dioxide (CO₂) absorption by microalgae in CMFC.     

Generation of electricity in microbial fuel cells at sub-ambient temperatures

Direct generation of electricity from a mixture of carbon sources was examined using single chamber mediator-less air cathode microbial fuel cells (MFCs) at sub-ambient temperatures. Electricity was directly generated from a carbon source mixture of d-glucose, d-galactose, d-xylose, d-glucuronic acid and sodium acetate at 30 °C and <20 °C (down to 4 °C). Anodic biofilms enriched at different temperatures using carbon source mixtures were examined using epi-fluorescent, scanning electron microscopy, and cyclic voltammetry for electrochemical evaluation. The maximum power density obtained at different temperatures ranged from 486 ± 68 mW m⁻² to 602 ± 38 mW m⁻² at current density range of 0.31 mA cm⁻² to 0.41 mA cm⁻² (14 °C and 30 °C, respectively). Coulombic efficiency increased with decreasing temperature, and ranged from 24 ± 3 to 38 ± 1% (20 °C and 4 °C, respectively). Chemical oxygen demand (COD) removal was over 68% for all carbon sources tested. Our results demonstrate adaptation, by gradual increase of cold-stress, to electricity production in MFCs at sub-ambient temperatures.     

Identification of removal principles and involved bacteria in microbial fuel cells for sulfide removal and electricity generation

Simultaneous sulfide and organics removals with electricity generation can be achieved in microbial fuel cells (MFCs). In present research, principles of sulfide removal as well as the involved bacteria in the MFCs with sulfide and glucose as the complex substrate are investigated. Results indicated that electrochemical and biological oxidations are the main effects for sulfide removal. Community analysis shows a great diversity of bacteria on the anode surface, including the exoelectrogenic bacteria and sulfur-related bacteria. They are present in greater abundance than those in the MFCs fed with only sulfide and responsible for the effective electricity generation and sulfide oxidation in our proposed MFCs. The results are conducive to reveal the interactions between the pollutants and microbes in aspects of pollutants removals and energy recovery in the MFCs for sulfide removal.