双室微生物燃料电池阴阳极间水传递特性

针对双室微生物燃料电池(dual chamber microbial fuel cell,DCMFC)中的水传输现象,研究了DCMFC中水传输现象产生的原因以及影响水传输量的各种因素。结果表明,在DCMFC中,阴阳极间水传输量随着放电电流的增大而增大;当阳极液为1500mg·L-1化学需氧量(COD)培养基和50 mmol·L-1磷酸缓冲盐的混合溶液、阴极液为50mmol·L-1 K3[Fe(CN)6]和50mmol·L-1磷酸缓冲盐的混合溶液,电池电流为5 mA时,电池阴阳极间的水传输量为0.045ml·h-1。此外,研究还表明,阴阳极间PBS溶液浓度差以及质子交换膜厚度对DCMFC的阴阳极间水传输量有着重要的影响。     

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材料的研究进展

微生物细胞向阳极转移电子的能力是微生物燃料电池(microbial fuel cell,简称MFC)功率密度低的重要影响因素之一,高性能的MFC阳极要易于产电微生物细胞附着生长,易于电子从微生物细胞向阳极传递,同时要求阳极内部电阻小、导电性强、阳极电势稳定.文章综述了MFC阳极材料的研究进展.     

微生物燃料电池处理含铬废水

采用双室的微生物燃料电池装置,探讨利用微生物燃料电池处理含铬废水的效率及电池性能.通过测定微生物燃料电池的电压、功率密度和电流密度,研究电池的性能,通过测定出水中Cr(Ⅵ)的浓度探讨微生物燃料电池对Cr(Ⅵ)的处理效率.结果表明,最大值出现在第21天,大约在18 mV左右;电压的最小值在0.5 mV左右,稳定值在2mV左右;装置稳定后,在电流密度等于0.526μA/cm2时,电池的电压达到最大值,为39.5 mV;当电流密度为1.328μA/cm2,功率密度达到最大值,为1.328×10-3mW/cm2;利用微生物燃料电池装置对Cr(Ⅵ)可以达到一定的处理效果,去除率约为20％.     

高效双室微生物燃料电池的运行特性

微生物燃料电池(MFC)在产生电流的同时还能处理糖蜜废水和电镀废水,并能从电镀废水中回收金属单质。本实验确定了电镀废水阴极液对双室微生物燃料电池产电性能的影响,阴极液分别采用银离子、铜离子和锌离子溶液作为MFC的阴极液,其初始浓度均配成1000mg/L。结果表明,锌离子作为阴极时MFC的产能效果最不理想,功率密度仅为1.9×10-6mW/m2。阴极为铜离子溶液时,可以获得相对大一些的功率密度(13.9mW/m2)。产能效果最好的是银离子阴极MFC,在电流密度为82.7mA/m2其获得最大功率密度为23.1mW/m2,COD去除率为71%,且其重金属去除率最大(72%),远远高于锌离子和铜离子。研究表明,重金属离子可以作为微生物燃料电池的阴极电子受体,MFC可以将有机废水中的化学能直接转化为电能,同时将重金属还原,具有显著的环境效益和经济效益。     

空气阴极微生物燃料电池研究进展

微生物燃料电池（MFC）是一种利用微生物做催化剂,处理废水的同时能产电的新型污水处理技术,因其＂变废为宝＂的能力而得到快速的发展。其中,以空气做阴极的单室MFC,因其省却了不断添加阴极液的过程、提高功率输出的同时降低成本而受到越来越多的关注。单室MFC装置可以分为管状、立方体状和短臂型结构,空气阴极的结构组成包括膜、催化层、集电材料、基层和扩散层。膜和催化层通常用热压法进行结合。目前报道的研究结果表明,有扩散层时获得的功率密度更高。已研究的扩散层的粘结剂有PTEF、PDMS、EF以及Nafion。选择合适的构型、催化剂以及扩散层的层数和粘结剂对改善电池产电性能极为重要。如何将多个装置串联以扩大废水处理量、提高功率密度的同时提高电子回收率是需要进一步解决的问题。     

微生物燃料电池产电的影响因素

以输出功率和内阻为评价指标,考察了直接微生物燃料电池在间歇运行过程中pH值、底物浓度、电极间距和添加电解质对产电性能的影响. 结果表明,pH值对输出功率影响较大,最佳值为7.5;输出功率随底物浓度的增大而增大．减小电极间距能有效降低电池内阻,提高输出功率,当电极间距为2 cm时,最大功率密度为700 mW/m2,内阻为80 W,库仑效率为7.7%. 磷酸盐缓冲溶液作为电解质对功率提高的效果优于NaCl,其添加量为100 mmol/L时,最大功率密度达922 mW/m2,内阻为70 W,库仑效率为11.5%.     

微生物燃料电池阳极材料的研究概况

综述了不同种类阳极材料(碳基材料、金属基材料、改性材料、天然材料和新型材料)在微生物燃料电池中的研究进展,对阳极材料在微生物燃料电池中作用机理进行了总结。探究了不同阳极材料所产生的输出功率、功率密度、电压、电流密度以及对污染物的降解效果,分析了提升产能的原因。对微生物燃料电池阳极材料的不足之处进行了阐述,对其未来发展提出了展望。     

活性炭修饰微生物燃料电池阳极的研究

利用活性炭修饰碳布作为微生物燃料电池阳极,并与多壁碳纳米管修饰的阳极和未修饰的碳布进行了的比较。结果表明,装配活性炭修饰碳布阳极运行的微生物燃料电池获得的最大功率密度为510 mW/m2,相较于多壁碳纳米管修饰的阳极和未修饰的碳布阳极分别提升了7%和54.5%。电极的电化学性质利用循环伏安法(CV)和交流阻抗谱(EIS)测试表明,活性炭修饰碳布具有良好的电化学特性。     

直接微生物燃料电池阴极的制备及优化

研究了直接微生物燃料电池阴极的制备方法,考察了制备过程中的主要影响因素,并通过功率密度曲线及伏安曲线对不同条件下制备的阴极性能进行了评价. 结果表明,防渗层中聚四氟乙烯含量、催化层中Nafion含量及整平层碳含量对阴极性能均有较大影响,当聚四氟乙烯浓度为30%及Nafion含量为2.8 mL、碳含量为0.18 g时,阴极性能最好,此时微生物燃料电池的输出功率密度为357 mW/m2, COD去除率达到90%.     

Continuous microbial fuel cell using a photoautotrophic cathode and a fermentative anode

A complete microbial fuel cell (MFC) operating under continuous flow conditions and using Chlorella vulgaris at the cathode and Saccharomyces cerevisiae at the anode was investigated for the production of electricity. The MFC was loaded with different resistances to characterise its power capabilities and voltage dynamics. A cell recycle system was also introduced to the cathode to observe the effect of microalgae cell density on steady‐state power production and dynamic voltage profiles. At the maximum microalgae cell density of 2140 mg/L, a maximum power level of 0.6 mW/m² of electrode surface area was achieved. The voltage difference between the cathode and anode decreased as the resistance decreased within the closed circuit, with a maximum open circuit voltage (infinite resistance) of 220 mV. The highest current flow of 1.0 mA/m² of electrode surface area was achieved at an applied resistance of 250 Ω.     

M-N-C阴极催化剂的制备及其在微生物燃料电池中的应用

以聚苯胺和硝酸盐为前驱体,采用热处理法制备了M-N-C（M=Fe,Co）材料,并将其作为厌氧流化床微生物燃料电池（AFBMFC）阴极催化剂。通过X射线衍射（XRD）、红外光谱（FTIR）、扫描电子显微镜（SEM）对催化剂进行晶型结构和表面形貌的表征。采用循环伏安法（CV）对催化剂的电化学性能进行考察,并应用于AFBMFC,考察了其对电池产电性能的影响。结果表明,使用Fe-N-C催化剂的微生物燃料电池稳定运行时,开路电压达到636.0 mV,功率密度达到166.82 mW·m^-2,比使用Pt/C催化剂的微生物燃料电池的功率密度提高10%。表明Fe-N-C催化剂用做微生物燃料电池阴极催化剂具有潜在的应用前景。     

Marine microbial fuel cell: Use of stainless steel electrodes as anode and cathode materials

Numerous biocorrosion studies have stated that biofilms formed in aerobic seawater induce an efficient catalysis of the oxygen reduction on stainless steels. This property was implemented here for the first time in a marine microbial fuel cell (MFC). A prototype was designed with a stainless steel anode embedded in marine sediments coupled to a stainless steel cathode in the overlying seawater. Recording current/potential curves during the progress of the experiment confirmed that the cathode progressively acquired effective catalytic properties. The maximal power density produced of 4 mW m⁻² was lower than those reported previously with marine MFC using graphite electrodes. Decoupling anode and cathode showed that the cathode suffered practical problems related to implementation in the sea, which may found easy technical solutions. A laboratory fuel cell based on the same principle demonstrated that the biofilm-covered stainless steel cathode was able to supply current density up to 140 mA m⁻² at +0.05 V versus Ag/AgCl. The power density of 23 mW m⁻² was in this case limited by the anode. These first tests presented the biofilm-covered stainless steel cathodes as very promising candidates to be implemented in marine MFC. The suitability of stainless steel as anode has to be further investigated.     

阳极双电层电容对微生物燃料电池性能的影响

采用3种活性炭粉制备具有不同电容的阳极,研究了双电层电容阳极对单室空气阴极微生物燃料电池启动、运行、性能、阳极生物膜附着的影响。结果表明:当电极表面积相近的情况下,阳极双电层电容从0.0012 F增加到22.72 F时,微生物燃料电池启动时间缩短了68.0%,电池的最大功率密度增加了16.8倍,达到546.1 m W·m-2。扫描电子显微镜的结果表明高电容的阳极表面附着的微生物量比低电容电极的高1倍。因此,微生物燃料电池性能受阳极双电层电容的影响,而与阳极表面积的相关性小。     

3D打印微生物燃料电池阳极及其性能特性

微生物燃料电池是一种处理废水同时产生电能的新型装置,阳极作为微生物燃料电池的重要组件极大地影响电池性能。针对微生物燃料电池传统三维电极结构不合理导致电极内部物质传输受限,电池功率密度较低的问题,本文采用3D打印技术并碳化的方式构建了结构可控的微生物燃料电池阳极,通过热重分析得到合适的碳化条件,并通过进一步的电化学分析和电极微观形貌拍摄研究了电极内部孔道结构对微生物生长情况和电池性能的影响。实验结果表明：电极孔径尺寸为0.4mm时,电池具有最优性能,其最大功率密度达12.85W/m²,比采用碳布阳极的MFC提升10倍,较采用碳毡阳极的燃料电池高38%;具有可控孔道结构电极的传荷阻抗和传质阻抗是限制电极性能的主要因素,通过优化孔道尺寸和结构分布可降低其传荷及传质阻抗,可以进一步提升电池性能。     

Effect of increasing anode surface area on the performance of a single chamber microbial fuel cell

The anode material and its configuration represent an important parameter in a microbial fuel cell (MFC), as it influences the development of the microbial community involved in the electrochemical bio-reactions.The aim of this work was to evaluate single chamber microbial fuel cells (SCMFCs) with high anode surface area, achieved by using packed beds of irregular graphite granules. The performance of the SCMFC with the packed bed anode configuration was studied using a mixed microorganism culture from real wastewaters in batch and continuous mode operation.The current output was found to increase with the increase in thickness of the anode bed and with the approximate anode area. The best performance was obtained with the 3 cm anode bed depth SCMFC. When the latter was operated in batch mode, Coulombic efficiencies varied from 30% to 74%, depending upon feed COD. In continuous mode operation, the COD removal was 89% and Coulombic efficiency 68% with a feed COD of 50 ppm, and at a flow rate of 0.0028 cm³ min^?1. Power performance was also reasonable with a volumetric power density of 1.3 W m^?3, with respect to the net anodic volume (12.5 cm³). Comparable performance was achieved with real wastewater. Over the duration of tests current output was stable. The investigation performed in this study represent a step forward for implementing real applications of MFC technology. A model of the current distribution in the packed bed electrode was applied, which correlates the effective utilization of the electrode to its specific area, solution conductivity and slope of the polarization curve. This model could function as a starting point in designing appropriate electrode geometries.     

A dual-chamber microbial fuel cell with conductive film-modified anode and cathode and its application for the neutral electro-Fenton process

This study reports on the modification of the anode and the cathode in a dual-chamber microbial fuel cell (MFC) with a polypyrrole (PPy)/anthraquinone-2,6-disulfonate (AQDS) conductive film to boost its performance and the application of the MFC to drive neutral electron-Fenton reactions occurring in the cathode chamber. The MFC equipped with the conductive film-coated anode and cathode delivered the maximum power density of 823 mW cm⁻² that was one order of magnitude larger than that obtained in the MFC with the unmodified electrodes. This was resulted from the enhanced activities of microbial metabolism in the anode and oxygen reduction in the cathode owing to the decoration of both electrodes with the PPy/AQDS composite. The MFC with the modified electrodes resulted in the largest rate of H₂O₂ generation in the cathode chamber by the two-electron reduction of O₂. The increase in the concentration of H₂O₂ was beneficial for the enhancement in the amount of hydroxyl radicals produced by the reaction of H₂O₂ with Fe²⁺, thus allowing an increased oxidative ability of the electro-Fenton process towards the decolorization and mineralization of an azo dye (i.e., Orange II) at pH 7.0.     

Electricity generation from terephthalic acid using a microbial fuel cell

BACKGROUND: Pure terephthalic acid (PTA) is a petrochemical product of global importance and is widely applied as an important raw material in making polyester fiber and polyethylene terephthalate (PET) bottles. In this work, a single‐chamber microbial fuel cell (MFC) was constructed using terephthalic acid (TA) with a chemical oxygen demand (COD) concentration range from 500 mg L^?1 to 3500 mg L^?1 as the electron donor and strain PA‐18 as the biocatalyst. RESLUTS: In the single chamber MFC, several factors were examined to determine their effects on power output, including COD concentration and electrode spacing. The characteristic of the strain PA‐18 was further studied. Cyclic voltammetry showed that electrons were directly transferred onto the anode by bacteria in biofilms, rather than self‐produced mediators of bacteria in the solutions. Scanning electron microscopy (SEM) observation showed that the anodic electrode surface was covered by bacteria which were responsible for electron transfer. Direct 16s‐rDNA analysis showed that the PA‐18 bacteria shared 99% 16SrDNA sequence homology with Pseudomonas sp. CONCLUSIONS: Electricity generation from TA in MFC was observed for the first time. The maximum power density produced by TA was 160 mW m^?2, lower than that achieved using domestic wastewater. This novel technology provided an economical route for electricity energy recovery in PTA wastewater treatment. High internal resistance was the major limitation. To further improve the power output, the electron transfer rate was accelerated by overexpression of membrane the protein gene of the strain PA‐18 and by reducing the electrolyte and mass transfer resistance by optimizing reactor configuration. Copyright © 2008 Society of Chemical Industry