利用生物活性炭提高微生物燃料电池产电性能

通过比较三组微生物燃料电池（MFC）的产电性能,考察使用生物活性炭（BAC）对提高MFC产电性能所起的作用。它们分别是：在阳极室内未投加活性炭的、投加了柱状活性炭的和投加了小颗粒活性炭的3种MFC。投加时机是在电池启动阶段,此时微生物在活性炭上驯化出生物膜,即形成生物活性炭,目的是辅助阳极富集更多微生物。结果表明,投加了小颗粒活性炭的MFC在产电性能和污水处理上具有优势。该电池最大容积功率密度达到1540 mW/m³ ,COD去除率达到了88%。     

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。     

以铁氰化钾为电子受体的MSBR-MFG集成系统响应机理研究

将双室微生物燃料电池(MFC)的阴极区改造成膜序批式生物反应器(MSBR),从产能和净化的双重角度构建了MSBR-MFC集成系统,以铁氰化钾作电子受体、碳毡作生物阴极和固定填料,采取"厌氧、好氧"交替运行方式处理城市生活污水,考察MSBR-MFC系统的产电能力及污染物去除效果.结果表明,系统在厌氧段加铁氰化钾后,电能输出将大幅提高,最适投加量为30mol·L-1;该条件下好氧段系统最大输出功率密度为893.1 mW·m-3,输出峰电压为570.4mV,电池内阻约300Ω,1个HRT(8h)内累积产电量13.6C;阴极区COD、氨氮、TP去除率分别为90.5%、99%和96.2%,阴阳两极室累积有机物去除容积负荷约2.125kg·m-3·-1,比传统双室MFC提高了约80.8%.     

温度对微生物燃料电池电化学性能的影响

分别在20℃,37℃和45℃三个温度条件下以间歇方式运行大肠杆菌生物燃料电池(MFC),研究功率密度、电极电势、电化学阻抗等电化学性质随温度的变化规律.结果表明:温度从20℃提高到37℃,最大功率密度从53.35 mW/m2 (275 mA/m2)增加到610.5 mW/m2(2775 mA/m2),增长了10.5倍;同时阳极电极电势降低;且阳极电化学阻抗由741.9 Ω降低到42.4 Ω.在一定温度范围内,升高温度不仅能提高电池功率输出,而且能增强其电化学活性.但是,太高的温度反而不利于生物燃料电池的运行.45℃时的最大功率密度只有171 mW/m2(600 mA/m2),比37℃时最大功率610.5 mW/m2(2 775 mA/m2)减少72％;同时阳极电化学阻抗由42.4 Ω增加到416.1 Ω.大肠杆菌生物燃料电池在37℃时具有最佳的电化学性能.可见,温度在生物燃料电池运行中是一个非常重要的操作参数.     

螺旋藻光合微生物燃料电池产电性能的研究

将微藻与微生物燃料电池(简称MFC)相结合,可以将太阳能转化成电能,这是一种可再生、稳定、高效的产能方式。本论文主要研究了螺旋藻作为MFC阳极产电微生物,以碳酸氢盐或葡萄糖作为底物的产电性能,并通过改变光照强度等条件,探讨影响微藻MFC产电性能的主要因素。以0.1mol/L的铁氰化钾溶液作为阴极液,外电阻为1000Ω,光照强度为12000lx,温度为28℃或30℃,进行电池的运行。螺旋藻MFC可以得到200mV的稳定输出电压,最大功率密度为41.33mW/m2,内阻为2000Ω。研究发现,螺旋藻MFC产生的电压主要依赖于生物膜上的藻,而与悬浮在阳极液中的藻无关。光照强度是影响产电的最主要因素之一,藻的输出电压随着光暗周期的变化表现出明显的周期性。     

连续流生物阴极微生物燃料电池废水处理与产电性能

微生物燃料电池(MFC)是一种利用微生物的新陈代谢作用将化学能转化为电能的装置。实验以石墨为电极材料,乙酸钠模拟废水为阳极底物,以厌氧活性污泥为厌氧菌种,驯化后的好氧污泥为好氧菌种,构建了双室连续流生物阴极MFC反应器。研究了连续流生物阴极MFC在降解乙酸钠废水同时的产电性能。结果表明,在外电阻为50Ω的情况下,未加NaCl溶液时,连续流好氧生物阴极MFC的最大电流密度为0.29 mA/m2,加入NaCl溶液后,最大电流密度为0.75 mA/m2,是未添加NaCl溶液MFC的2.59倍,输出功率密度是未加NaCl溶液的6.84倍。阳极室出水进入阴极室,研究了连续流好氧生物阴极废水处理效果。结果表明,COD的去除率随MFC运行时间的增加呈上升趋势,MFC稳定运行后,COD的去除率维持在60.1%～66%。     

分配比对分段进水双阴极MFC脱氮产电性能的影响

为提高双阴极MFC的脱氮性能,构建了分段进水的双阴极微生物燃料电池系统,以考察了厌氧室和缺氧室分段进水的进水分配比MFC脱氮产电性能的影响。通过监测实验过程中各极室NO_3~--N、NO_2~--N、NH_4~+-N、COD的去除情况以及MFC各项产电指标的变化情况,分析进水分配比对电池性能的影响。结果表明:采用分段进水的MFC能有效提高MFC对总氮的去除效果,进水配水比为1∶1时对TN的去除效果最好,去除率由49.89%提升至79.94%;缺氧室进水流量越高对NO_3~--N的去除效果越好,进水配水1∶3时,NO_3~--N出水浓度由17.28 mg·L~(-1)降至2.93 mg·L~(-1)。分段进水对产电性能的抑制明显,尤其是在缺氧阴极,缺氧室进水流量越高抑制越明显,缺氧阴极的功率密度由100.63 mW·m~(-3)降低至0.03 mW·m~(-3)。本研究探明了进水配水比对分段进水双阴极MFC脱氮产电性能的影响,为进一步提高MFC脱氮产电性能提供依据。     

MFC处理低浓度焦化废水的试验研究

使用单室空气阴极微生物电池处理焦化废水,以电压、电流密度、功率密度、COD去除率、p H为考察指标,分别用铂、四氧化三铁、二氧化锰作阴极,对比其去除效率和产电能力。实验结果表明,铂阴极的产电能力和废水处理效果最好,开路电压最大值达到521.469 m V。当电流密度为2.4 A/m2时功率密度达到最大值0.195 W/m2,COD去除率为82.9%;二氧化锰阴极MFC效果次之,四氧化三铁阴极MFC的效果最差。     

微生物燃料电池对废水中对硝基苯酚的去除

在以碳纸为阳极、空气电极为阴极、葡萄糖和对硝基苯酚为混合燃料的直接空气阴极单室微生物燃料电池中,考察了微生物燃料电池(MFC)对对硝基苯酚的降解及MFC的产电特性.结果表明MFC对废水中不同浓度的对硝基苯酚均有一定的去除效果,400 mg/L的对硝基苯酚降解4d的去除率74.1%,降解6 d的去除率为82.1%.MFC的输出电压最高为0.293V(外阻1 000Ω),最大输出功率密度为56.5 mW/m3.     

基于进水流速的连续流小球藻MFC性能研究

针对规模化养殖源分离废水的特点和当代水处理技术存在的问题,在间歇流MFC研究的基础上,基于同步废水处理、产电能及小球藻生物质能回收,进行了连续流小球藻生物阴极型MFC对源分离养猪废水的处理实验。研究发现MFC在5种不同进水流速条件下,当流速为1 mL/6.5 min时,稳定输出电压值、库仑效率和最大功率密度达到最大值,分别为537.26±23.78 mV、14.39%±0.58%和2 740.30 mW/m~3;COD去除率随着进水流速的减小逐渐增大,在1 mL/10 min进水流速时达到最大,为77.58%±0.48%;当进水流速为1 mL/3.0 min时,MFC的内阻达到最大,为437.14Ω;减小阳极进水流速为1 mL/5.0 min后,MFC得到了最小的内阻值,为195.73Ω,较1 mL/6.5 min与1mL/10.0 min进水流速时分别低了7.63%与25.14%;从产电性能、COD去除效果、阴极微藻生长状况及阴极溶解氧浓度等方面综合分析,该MFC在进水流速为1 mL/6.5 min时,系统整体性能表现最佳。     

以加热预处理污泥上清液为底物的微生物燃料电池基础特性

以单室空气阴极微生物燃料电池(MFC)为反应器,考察了以加热预处理污泥上清液为底物的MFC产电情况. 结果表明,污泥90℃下加热3 h时MFC输出功率最高(44.4 mW/m2),是未加热的105倍. 在此预处理条件下,污泥上清液中所含有机物成分最有利于阳极微生物的代谢产电. 加热后的污泥再次加热作为MFC底物产电,输出功率只有5.8 mW/m2. 加热预处理可提高以污泥上清液为底物的MFC的输出功率,且易与现有工艺结合,更接近实际应用.     

Electricity generation with simultaneous wastewater treatment by a microbial fuel cell (MFC) with Cu and Cu–Au electrodes

Background: A microbial fuel cell (MFC) consisting of anaerobic and aerobic chambers separated by a salt‐agar slab was used for electricity generation with simultaneous wastewater treatment where copper and gold covered copper wires were used as anode and cathode, respectively. The electrons produced from degradation of carbohydrates in anaerobic chamber traveled through the copper wire generating electricity and the protons were transferred from cathode to anode through the salt‐agar slab. Variation of the current intensity (mA) and the electrical power (mW) were investigated as function of the surface area of anode and also the chemical oxygen demand (COD) content of the synthetic wastewater. Results: The generated power density (mW m^?2) increased with increasing surface area of the electrodes and also with the COD content of the wastewater. Both the current intensity (mA) and the power generated (mW) increased with time and reached maximum levels at the end of batch operation. More than 80% COD removal was achieved in the aerobic chamber with an electricity generation of 2.9 mW m^?2 when the initial COD content was 6000 mg l^?1. Conclusion: The MFC configuration and the use of Cu and Cu‐Au electrodes instead of graphite were proven to be effective for electricity generation with simultaneous wastewater treatment. The electrical current (0.24 mA) and power (2.9 mW m^?2) obtained in our microbial fuel cell are comparable with the literature studies utilizing salt bridge. The microbial fuel cell developed in this study can be improved further to yield higher power generations by modifications. Copyright © 2007 Society of Chemical Industry     

不同运行方式对微生物燃料电池处理氨氮废水的影响

微生物燃料电池(MFC)是一种既能去除污染物又能产电的新型污水处理技术,由于其具有利用生物转化能量的节能优势,MFC废水脱氮处理技术引起了更多的关注。本实验在启动MFC的同步硝化与反硝化(SND)后,首先研究了通路与断路条件对MFC产电脱氮的影响,结果表明:断路时有利于硝化反应的发生,氨氮去除率有最大值95.17%;而通路更有利于COD和总氮的去除,表明氮的去除主要依靠阴极接受电子进行。随后分析了曝气阶段+停曝阶段运行方式对MFC产电和脱氮的影响,结果显示:曝气8.5h(DO为4.0mg/L)后停止曝气,停曝阶段为11.5h,DO逐渐降低到2.0mg/L,输出电压由无曝气运行的31mV提高到120mV左右,氨氮去除率最高达到86.42%、总氮去除负荷由无曝气运行的0.064g/(L·d)升高到0.46g/(L·d)。说明曝气阶段+停曝阶段运行方式既能有效提高MFC脱氮产电性能又可以减少维持高浓度DO的能量输入。     

Increased generation of electricity in a microbial fuel cell using <Emphasis Type="Italic">Geobacter sulfurreducens</Emphasis>

The microbial fuel cell (MFC) has attracted research attention as a biotechnology capable of converting hydrocarbon into electricity production by using metal reducing bacteria as a biocatalyst. Electricity generation using a microbial fuel cell (MFC) was investigated with acetate as the fuel and Geobacter sulfurreducens as the biocatalyst on the anode electrode. Stable current production of 0.20–0.24 mA was obtained at 30–32 °C. The maximum power density of 418–470 mW/m², obtained at an external resistor of 1,000 Ω, was increased over 2-fold (from 418 to 866 mW/m²) as the Pt loading on the cathode electrode was increased from 0.5 to 3.0 mg Pt/cm². The optimal batch mode temperature was between 30 and 32 °C with a maximum power density of 418–470 mW/m². The optimal temperature and Pt loading for MFC were determined in this study. Our results demonstrate that the cathode reaction related through the Pt loading on the cathode electrode is a bottleneck for the MFC’s performance.     

Preliminary Study on E. coli Microbial Fuel Cell and On-electrode Taming of the Biocatalyst

A mediator microbial fuel cell (MFC) was constructed by using E. coli as biocatalyst and new methylene blue as electron mediator. E. coli cells were carried out in anaerobic growth prior to inoculating them into the MFC in order to pre-adapt bacterial metabolism in an anaerobic environment, the electricity generation of MFC was tested, its maximum power density reached 263.94 mW/m2 with the corresponding current density 1287.50 mA/m2, the internal resistance of MFC was 200 W, and capability of the MFC was even better than those reported so far. Moreover, on-electrode taming method was adopted to improve electrochemical activity of E. coli, namely a combination of E. coli taming and electricity generation simultaneously in the same MFC without scraping off the biofilm of MFC, after the 4th on-electrode taming, the tamed E. coli MFC showed a 54% improvement in peak current density, being 612.50 mA/m2, and a 64% improvement in the maximum power output, being 166.67 mW/m2, compared with that of parental E. coli MFC. And the maturation time of tamed biofilm was obviously reduced to 240 min, quickening up 1 times compared with that of parental E. coli biofilm.     

厌氧流化床无膜微生物燃料电池的床层膨胀高度与产电特性

考察了厌氧流化床床层膨胀高度对电池不同阴极位置(阴极1, 2, 3分别位于分布板上方150, 250, 350 mm)产电性能的影响. 膨胀高度低于170 mm时,电池功率随阴极位置沿轴向高度增加而减小,同一流速下,阴极1的最大电极输出功率最大,为347.1 mW/m2. 膨胀高度在170~270 mm时,同一流速下,阴极2的最大产电功率高于阴极1和阴极3,当流速为8.35 mm/s 时,达361.0 mW/m2. 膨胀高度在400 mm以下,同一流速下3处阴极的最大产电功率均降低,阴极3最大产电功率降低幅度较小,为297.5 mW/m2,电池功率随阴极位置沿轴向高度增加而增大. 该结果是流速对阳极室内传质及电子传递效率、流速对微生物膜生长双重影响的结果.     

Evaluation of applied cathode potential to enhance biocathode in microbial fuel cells

BACKGROUND: The biocathode is proving to be a promising feature for development of the microbial fuel cell (MFC), although much work remains to be done to increase its power generation. This study aimed to enhance the performance of a biocathode by applying selected cathode potential. RESULTS: When five two‐chambered MFCs were operated at selected cathode potentials of 142, 242, 342, 442, or 542 mV (vs standard hydrogen electrode), those MFCs with selected potentials lower than 342 mV could start up, and the highest power density of 0.11 W m^?3 was obtained at a selected potential of 242 mV. An inner‐biocathode MFC was then constructed and operated at a start‐up cathode potential of 242 mV for 30 days. The open circuit cathode potential increased from 477 ± 9 mV to 572 ± 8 mV compared with the potential of the initially abiotic cathode, resulting in an increase in the maximum power density (4.25 ± 0.16 W m^?3) of 106%. In addition, tests of continuous operation showed that a loading rate of 135 mg COD L^?1 d^?1 was optimal for obtaining maximum power generation in the system developed for this study. CONCLUSION: The results indicated that an optimal cathode potential of 242 mV enhanced the performance of a biocathode using oxygen as the electron acceptor. Copyright © 2009 Society of Chemical Industry     

A Single-Chamber Microbial Fuel Cell without an Air Cathode

Microbial fuel cells (MFCs) represent a novel technology for wastewater treatment with electricity production. Electricity generation with simultaneous nitrate reduction in a single-chamber MFC without air cathode was studied, using glucose (1 mM) as the carbon source and nitrate (1 mM) as the final electron acceptor employed by Bacillus subtilis under anaerobic conditions. Increasing current as a function of decreased nitrate concentration and an increase in biomass were observed with a maximum current of 0.4 mA obtained at an external resistance (R(ext)) of 1 KΩ without a platinum catalyst of air cathode. A decreased current with complete nitrate reduction, with further recovery of the current immediately after nitrate addition, indicated the dependence of B. subtilis on nitrate as an electron acceptor to efficiently produce electricity. A power density of 0.0019 mW/cm(2) was achieved at an R(ext) of 220 Ω. Cyclic voltammograms (CV) showed direct electron transfer with the involvement of mediators in the MFC. The low coulombic efficiency (CE) of 11% was mainly attributed to glucose fermentation. These results demonstrated that electricity generation is possible from wastewater containing nitrate, and this represents an alternative technology for the cost-effective and environmentally benign treatment of wastewater.     

Cu2O/rGO复合材料修饰阴极强化MFC产电脱氮性能及其机理

微生物燃料电池(MFC)在处理含硝酸盐(NO_3^--N)废水时具有同时产电和脱氮的潜力,寻找成本低且改善其产电脱氮性能的阴极修饰材料是MFC在含氮废水处理领域应用的关键。氧化亚铜/还原氧化石墨烯(Cu₂O/rGO)复合材料具有良好的电化学性能,在替代铂基材料提高MFC性能方面具有一定的应用前景。本研究通过还原法制备了Cu₂O/rGO复合材料,并对材料的结构和氧还原性能进行表征；同时,将其负载于阴极碳布后分析其电化学性能,并通过MFC的输出电压、功率密度和NO_3^--N的去除率探究Cu₂O/rGO阴极对MFC产电和脱氮性能的强化作用；通过对反硝化相关酶活性和胞外聚合物的测定,探究Cu₂O/rGO阴极强化MFC性能的机理。结果表明：Cu₂O/rGO复合材料具有大量的介孔结构,能够为电子传递提供更多的通道,并且Cu₂O/rGO复合材料具有良好的氧化还原可逆性；与Pt/C阴极相比,Cu₂O/rGO阴极的交换电流密度升高33.53%,电子转移阻力降低65.53%；Cu₂O/rGO-MFC在处理NO_3^-N废水时获得的最大平均输出电压(662.54 mV)、最大功率密度(26.27 mW/cm^₂)、平均库伦效率(32.02%)和NO_3^--N去除速率(83.33 mg NO_3^--N L/h)均高于Pt/C-MFC(485.33 mV,16.98 mW/cm^₂,7.38%,41.67 mg NO_3^--N L/h)；Cu₂O/rGO复合材料通过提高MFC阴极反硝化关键酶活性和类蛋白组分含量,改善了MFC的产电和脱氮性能。