微生物燃料电池中阳极产电菌的研究进展

微生物燃料电池(MFCs)是一种生物电化学混合系统,利用微生物的氧化代谢作用将有机物或者无机物中的能量转化为电能,具有节能、减少污泥生成及能量转换的突出优势,已引起广泛关注。其中,产电微生物是MFCs系统的核心组成部分,筛选及培养高效产电微生物对促进MFCs的产电性能具有重要作用。对产电微生物电子传递机制、产电微生物种类以及影响微生物产电的因素进行分析总结;综述了阳极产电微生物的最新研究进展;最后,从微生物角度展望了阳极产电微生物未来的研究方向,以期为产电微生物在MFCs中的应用提供指导和支持。     

同步废水处理及产电的微生物燃料电池研究进展

同步废水水处理及产电的微生物燃料电池是利用生物催化剂直接把化学能转化为电能,具有能量转化率高、污泥产率低、反应条件温和等优点。本文阐述了微生物燃料电池的工作原理及电子传递机理,综述了其最新的研究进展,并对微生物燃料电池在污水处理领域的发展方向作了展望。     

微生物燃料电池的研究进展与展望

微生物燃料电池(MFCs)作为一种新型的环境生物技术,因其能很好地将有机污染物处理和能源制备结合在一起而引起各国学者的广泛关注和研究。作者介绍了微生物燃料电池的工作原理,系统地从微生物、底物、电活性介体、电极构造、质子交换膜和反应器设计等方面阐述了微生物燃料电池的研究现状。针对微生物燃料电池今后的发展和规模化应用,提出了4个研究方向:新型阴极氧化剂的研制、MFCs过程模拟、厌氧-MFCs耦合、多个MFCs电池组性能。     

微生物燃料电池阳极的研究进展

产电微生物与电池阳极之间的电子传递效率是影响微生物燃料电池（MFC）产电性能的重要因素之一.通过对阳极材料的改进和修饰可以有效地降低阳极反应的活化能垒,提高电子传递效率,进而提高MFC产电性能.详细介绍了近年来MFC阳极材料的国内外研究进展,并针对当前研究所面临的问题,提出了今后MFC阳极的发展方向.     

微生物燃料电池的研究进展

根据有无电子传递中间体的参与,微生物燃料电池可分为两大类：直接和间接微生物燃料电池. 简要介绍了其工作原理及发展历史,归纳了近年来国内外对这两种类型电池的研究现状,特别概括了直接微生物燃料电池的研究进展以及存在的问题和工作方向. 最后展望了微生物燃料电池的应用前景.     

微生物燃料电池阳极修饰的研究进展

微生物细胞与电池阳极之间的电子转移速率是影响微生物燃料电池(MFC)产电性能的重要因素之一.通过阳极修饰可以促进电子转移速率,进而提高MFC产电性能.综述了MFC阳极修饰的研究进展.     

微生物燃料电池最新研究进展

介绍了微生物燃料电池(MFC)的原理、组成和特点,并针对MFC功率密度过低、构造成本高等问题,从筛选优势产电微生物、改善MFC的构造、优化电极材料以及提高电子传递效率等方面进行了介绍,同时还提到了提高产电性能的各种途径,最后对MFC的发展前景进行了展望.     

微生物燃料电池阳极产电菌的选育

产电菌能够以微生物燃料电池的阳极作为唯一的电子受体完成有机物的氧化,在产电的同时获得自身生长所需的能量。基于产电菌的特殊代谢方式,有望在处理有机废水的过程中获取电能。分离和培养产电菌是研究其产电过程的基础。本研究采用双层平板技术从厌氧颗粒污泥中分离出数个产电菌株,采用循环伏安法(cyclic voltammograms,CV)对厌氧培养的产电菌进行曲线扫描,所得曲线表明这些产电菌具有一定的电化学活性,可以用来进行产电实验。     

微生物燃料电池的研究进展

介绍了微生物燃料电池的工作原理。列举了微生物燃料电池的3个实例模型。概括了微生物燃料电池目前存在的问题和解决方法。展望了微生物燃料电池的应用前景。     

微生物燃料电池技术及其影响因素研究进展

微生物燃料电池(Microbial fuel cell,MFC)作为一种绿色能源技术,通过微生物的氧化代谢作用将废水中的有机质降解的同时产生电能.然而,其相对较低的产电效率限制了MFC的工业化应用.该文介绍了影响MFC性能的诸多因素,如设备的构型限制、电极材料、阳极底物、阳极微生物和质子交换膜等,提出优化MFC的设计,提高MFC的产电性能,降低投入成本可解决MFC产业化应用的弊端,并对未来MFC的发展方向进行了展望.     

Electrochemical activity of Geobacter sulfurreducens biofilms on stainless steel anodes

Stainless steel was studied as anode for the biocatalysis of acetate oxidation by biofilms of Geobacter sulfurreducens. Electrodes were individually polarized at different potential in the range −0.20 V to +0.20 V vs. Ag/AgCl either in the same reactor or in different reactors containing acetate as electron donor and no electron acceptor except the working electrode. At +0.20 V vs. Ag/AgCl, the current increased after a 2-day lag period up to maximum current densities around 0.7 A m⁻² and 2.4 A m⁻² with 5 mM and 10 mM acetate, respectively. No current was obtained during chronoamperometry (CA) at potential values lower than 0.00 V vs. Ag/AgCl, while the cyclic voltammetries (CV) that were performed periodically always detected a fast electron transfer, with the oxidation starting around −0.25 V vs. Ag/AgCl. Epifluorescent microscopy showed that the current recorded by chronoamperometry was linked to the biofilm growth on the electrode surface, while CVs were more likely linked to the cells initially adsorbed from the inoculum. A model was proposed to explain the electrochemical behaviour of the biofilm, which appeared to be controlled by the pioneering adherent cells playing the role of “electrochemical gate” between the biofilm and the electrode surface.     

Electron transfer pathways in microbial oxygen biocathodes

The ability of some bacteria to enhance the rate of cathodic oxygen reduction to water has been recently discovered, opening the way to an entirely renewable and environmentally friendly concept of biocathode. In this study we reveal that several mechanisms may induce catalytic effects by bacteria. These comprise mechanisms that are putatively beneficial to the bacteria as well as mechanisms which are merely side effects, including quinone autoxidation and direct O₂ reduction by heme compounds. Here we showed that 1 μM of ACNQ is able to generate a significant catalytic wave for oxygen reduction, with onset at approximately 0 V vs. SHE. Similarly, adsorption of hemin on a carbon surface catalyses O₂ reduction to H₂O₂ with an onset of +0.2 V vs. SHE. To evaluate the catalytic pathways of live cells on cathodic oxygen reduction, two species of electrochemically active bacteria were selected as pure cultures, namely Acinetobacter calcoaceticus and Shewanella putrefaciens. The former appears to exploit a self-excreted redox compound with redox characteristics matching those of pyrroloquinoline quinone (PQQ) for extracellular electron transfer. The latter appears to utilise outer membrane-bound redox compounds. Interaction of quinones and cytochromes with the membrane-bound electron transfer chain is yet to be proven.     

微生物燃料电池研究和应用方面的最新进展

微生物燃料电池是一种利用微生物的催化作用将化学能转变为电能的生物装置。微生物燃料电池在作为可替代性能源、新颖的污水处理方法以及氧和污染物的生物传感器等方面具有较大的潜能,但仍需进一步优化。本文确定了限制微生物燃料电池应用操作的几种因素,并在其性能提高方面进行了探讨。     

Effect of temperature on the performance of microbial fuel cells

Single and double chamber microbial fuel cells (MFCs) were tested in batch mode at different temperatures ranging from 4 to 35 °C; results were analysed in terms of efficiency in soluble organic matter removal and capability of energy generation. Brewery wastewater diluted in domestic wastewater (initial soluble chemical oxygen demand of 1200 and 492 mg L⁻¹ of volatile suspended solids) was the source of carbon and inoculum for the experiments. Control reactors (sealed container with support for biofilm formation) as well as baseline reactors (sealed container with no support) were run in parallel to the MFCs at each temperature to assess the differences between water treatment including electrochemical processes and conventional anaerobic digestion (in the presence of a biofilm, or by planktonic cells). MFCs showed improvements regarding rate and extent of COD removal in comparison to control and baseline reactors at low temperatures (4, 8 and 15 °C), whilst differences became negligible at higher temperatures (20, 25, 30 and 35 °C). Temperature was a crucial factor in the yield of MFCs both, for COD removal and electricity production, with results that ranged from 58% final COD removal and maximum power of 15.1 mW m⁻³ reactor (8.1 mW m⁻² cathode) during polarization at 4 °C, to 94% final COD removal and maximum power of 174.0 mW m⁻³ reactor (92.8 mW m⁻² cathode) at 35 °C for single chamber MFCs with carbon cloth-based cathodes. Bioelectrochemical processes in these MFCs were found to have a temperature coefficient, Q10 of 1.6.A membrane-based cathode configuration was tested and gave promising results at 4 °C, where a maximum power output of 294.6 mW m⁻³ reactor (98.1 mW m⁻² cathode) was obtained during polarization and a maximum Coulombic efficiency (Y_Q) of 25% was achieved. This exceeded the performance at 35 °C with cloth-based cathodes (174.0 mW m⁻³; Y_Q 1.76%).     

The internal resistance of a microbial fuel cell and its dependence on cell design and operating conditions

The internal resistance R_int of a mediator-less microbial fuel cell (MFC) has been determined as a function of cell voltage using electrochemical impedance spectroscopy (EIS) for a MFC with and without Shewanella oneidensis MR-1. The same tests were performed for a MFC containing small stainless steel (SS) balls in the anode compartment with a graphite feeder electrode as in a packed bed cell. It has been found that R_int decreased with decreasing cell voltage as the increasing current flow decreases the polarization resistance of the anode and the cathode. The ohmic components of R_int played a very minor role. In the presence of MR-1 R_int was lower by a factor of about 100 than R_int of the MFC with buffer and lactate as anolyte. R_int was also significantly lower for the anode containing SS balls with buffer and lactate as anolyte. For the MFC containing SS balls in the anode compartment no significant further decrease of R_int could be obtained when MR-1 was added to the anolyte since in this case the polarization resistance of the anode was lower than that of the cathode. Similar trends were observed in the cell voltage (V)-current (I) curves that were obtained using potentiodynamic sweeps and the power (P)-V curves that were calculated from the V-I curves.     

厌氧活性污泥产电特性及产电过程微生物群落变化

以厌氧活性污泥为接种液构建微生物燃料电池(MFC),检测了运行第1周期前后电池的理化性质及菌群变化情况。结果表明,MFC启动后产电性能良好,外接1000 Ω电阻时输出电压可达0.62 V,功率密度达1247 mW/m2,内阻为143 Ω, 化学需氧量(COD)去除率达63.6%;高通量测序结果显示,MFC菌群与原始接种厌氧活性污泥菌群相比变化较明显,菌群多样性指数降低,优势菌门硬壁菌门(Firmicutes)和变形菌门(Proteobacteria)为产电菌群常见门,与MFC产电能力直接相关的克雷伯氏菌属(Klebsiella)富集并成为优势菌属,相对丰度达16.73%。     

Analysis of PEM fuel cell stacks using an empirical current–voltage equation

An empirical equation was developed to describe the electrode processes (activation, ohmic and mass-transfer) of PEMFC stacks over the entire current range. The potential–current and power–current curves of a strip PEMFC stack were fitted with the empirical equation under a variety of experimental humidity, temperature and stack length conditions. The concept of mass transfer impedance was defined mathematically in the present research. For the strip PEMFC stack, mass transfer impedance was only important at high currents. With decreasing humidity the mass transfer impedance increased considerably. With increasing temperature or stack cell number the mass transfer impedance increased only slightly.