单室微生物燃料电池

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微生物燃料电池的发展现状及未来趋势

微生物燃料电池的发展现状及未来趋势一、引言随着能源资源的紧缺和环境污染的加剧，寻求替代能源和清洁能源的研究日益受到关注。

微生物燃料电池作为一项新兴技术，被认为具有巨大潜力，可以转化废弃物为清洁能源。

本文将探讨微生物燃料电池的发展现状及未来趋势。

二、微生物燃料电池的原理微生物燃料电池是一种利用微生物催化底物氧化反应并直接将化学能转化为电能的技术。

它以微生物作为催化剂，将底物（如有机废弃物）氧化为电子和质子，并通过电化学反应转变为电能。

这种技术具有可持续性和高效能的特点，因此备受瞩目。

三、微生物燃料电池的应用领域1.废水处理微生物燃料电池可以应用于废水处理领域，通过将微生物直接放置在废水中进行催化反应，实现废水的净化并产生电能。

这种技术可以将废水处理和能源回收结合，减轻环境污染的同时获得经济利益。

2.生物传感器微生物燃料电池还可以应用于生物传感器领域，利用微生物对特定环境参数的敏感性，通过监测微生物燃料电池的输出电流变化来实现环境监测和生物检测。

这种技术具有实时性和高灵敏度，可以在环境监测、医学诊断等方面发挥重要作用。

四、微生物燃料电池的发展现状目前，微生物燃料电池的开发已经取得了一定的进展。

研究人员已经成功地利用不同类型的微生物，如厌氧细菌、藻类和真菌，来催化底物的氧化反应。

同时，改进了电极材料和设计，提高了微生物燃料电池的输出电流和效率。

许多实验室已经实现了小规模的微生物燃料电池系统，并取得了良好的效果。

五、微生物燃料电池的未来趋势尽管微生物燃料电池在废水处理和生物传感器等领域已经初步应用，但仍存在一些挑战和限制。

首先，微生物燃料电池的输出电流和效率仍然较低，需要进一步提高。

其次，微生物的选择和培养条件对整个系统的性能有重要影响，需要更深入的研究和优化。

此外，微生物燃料电池的商业化应用面临着技术成本和市场需求等问题。

未来，微生物燃料电池的发展方向主要包括以下几个方面。

首先，通过细菌基因工程的技术手段，优化微生物的催化性能，提高其氧化底物的效率。

用醋酸盐和丁酸盐进行产电的单室微生物燃料电池(英文)

Production of Electricity from Acetate or Butyrate Using aSingle-Chamber Microbial Fuel CellH O N G L I U ,†S H A O A N C H E N G ,†A N D B R U C E E .L O G A N *,†,‡Department of Civil and Environmental Engineering,and The Penn State Hydrogen Energy (H 2E)Center,The Pennsylvania State University,University Park,Pennsylvania 16802Hydrogen can be recovered by fermentation of organic material rich in carbohydrates,but much of the organic matter remains in the form of acetate and butyrate.An alternative to methane production from this organic matter is the direct generation of electricity in a microbial fuel cell (MFC).Electricity generation using a single-chambered MFC was examined using acetate or butyrate.Powergenerated with acetate (800mg/L)(506mW/m 2or 12.7mW/L)was up to 66%higher than that fed with butyrate(1000mg/L)(305mW/m 2or 7.6mW/L),demonstrating that acetate is a preferred aqueous substrate for electricity generation in MFCs.Power output as a function of substrate concentration was well described by saturation kinetics,although maximum power densities varied with the circuit load.Maximum power densities and half-saturationconstants were P max )661mW/m 2and K s )141mg/L for acetate (218Ω)and P max )349mW/m 2and K s )93mg/L for butyrate (1000Ω).Similar open circuit potentials were obtained in using acetate (798mV)or butyrate (795mV).Current densities measured for stable power output were higher for acetate (2.2A/m 2)than those measured in MFCs using butyrate (0.77A/m 2).Cyclic voltammograms suggested that the main mechanism of power production in these batch tests was by direct transfer of electrons to the electrode by bacteria growing on the electrode and not by bacteria-produced mediators.Coulombic efficiencies and overall energy recovery were 10-31and 3-7%for acetate and 8-15and 2-5%for butyrate,indicatingsubstantial electron and energy losses to processes other than electricity generation.These results demonstrate that electricity generation is possible from soluble fermentation end products such as acetate and butyrate,but energy recoveries should be increased to improve the overall process performance.IntroductionHarvesting products from wastewater in order to make the process more economical and sustainable is the next frontier in wastewater treatment (1,2).Hydrogen production from wastewater by biological fermentation has drawn much attention as a method of producing a valuable product during treatment of wastewaters containing high concentrations ofcarbohydrates (3-7).One mole of glucose can theoreticallybe converted into 12mol of hydrogen,but the maximum yield via known fermentation routes is only 4mol of hydrogen when acetate is the sole byproduct.While the maximum efficiency of hydrogen production is therefore 33%,typically only 15%of the energy is recovered as hydrogen (2,8)with the remainder of the organic matter present as fatty acids and alcohols.To improve the economics of hydrogen production from wastewater,additional processes are needed to recovery the remaining energy.One approach is to link hydrogen pro-duction with methane production by using a two-stage process (2).Although two-stage anaerobic treatments have been used to make methane,it has not yet been proven outside of the laboratory that hydrogen can be recovered at high concentrations from the first stage using actual waste-waters.A second approach is to use phototrophic bacteria to recover additional hydrogen from the byproducts of hydrogen fermentation (9,10).Although solar energy is free,the availability of sufficient land area and the instability of sufficient solar energy at the plant would make such a process difficult for wastewater treatment applications.A third approach is to recover the remaining energy directly as electricity in a microbial fuel cell (MFC).While electricity production has been shown in MFCs using glucose or acetate,much remains to be done in order to use this technology for wastewater treatment.Bacteria present in wastewater,anaerobic reactor sludges,and marine sediments have been shown to produce electricity in a MFC (11-14).Bacteria that have been identified to be capable of making electricity in fuel cells,most of which are metal-reducing bacteria,include Geobacter sulfurreducens (15,16),Geobacter metallireducens (13,16),Shewanella putrefaciens (17,18),Clostridium butyricum (19),Rhodoferax ferrireducens (20),and Aeromonas hydrophila (15).It has also been recently shown that electricity generation in an MFC resulted in large part from the production of mediators,or electron shuttles,by a microbial community consisting of primarily three bacteria:Alcaligenes faecalis ,Enterococcus faecium ,and Pseudomonas aeruginosa (12).Many MFCs contain two chambers (16-18,20).One chamber contains electrochemically active bacteria growing under anaerobic conditions that grow as a biofilm attached to the anode.The other chamber is kept aerobic by sparging water with air and contains the cathode.The two chambers are typically separated by a proton exchange membrane (PEM),which allows the transfer of protons from the anode to cathode chamber and that helps to physically block oxygen diffusion into the anode chamber.Recently,single-chamber MFCs have been developed that use a cathode exposed directly to air instead of air-sparged water (11,21,22).There are several advantages of using a single-chamber MFC versus a two-chambered system:increased mass transfer to the cathode;decreased operating costs,because it is not neces-sary to sparge the water;an overall decrease in reactor volume;and a simplified design.Power output can further be increased in a single-chamber MFC by removing the PEM (11).Although there is increased oxygen diffusion into the anode chamber in the absence of the PEM,the formation of an aerobic biofilm on the cathode inner surface (facing the anode)removes any oxygen that diffuses into the chamber,preventing the loss of anaerobic conditions in the anode chamber.The lack of a PEM also substantially decreases the cost of the materials needed to make a MFC.The primary fermentation end products during biohy-drogen production are acetic and butyric acids.Thus,to link*Corresponding author phone:814-863-7908;fax:814-863-7304;e-mail:blogan@.†Department of Civil and Environmental Engineering.‡The Penn State Hydrogen Energy (H 2E)Center.Environ.Sci.Technol.2005,39,658-6626589ENVIRONMENTAL SCIENCE &TECHNOLOGY /VOL.39,NO.2,200510.1021/es048927c CCC:$30.25©2005American Chemical SocietyPublished on Web 12/03/2004a MFC to biohydrogen production it must be shown that power can be generated from degradation of these com-pounds.However,there are no previous studies on electricity production from butyrate,which can account for up to 70%of the aqueous byproducts of hydrogen production from sugar fermentation (8).Power generation from acetate in two-chambered MFCs is well known,but there have been no previous reports of power generation using acetate in single-chambered systems.Here we demonstrate that electricity can be generated from butyrate in a single-chambered MFC,and we compare power densities obtained from acetate and butyrate with those previously obtained in the same system using glucose (11).MethodsMFC Construction and Operation.The membrane-free single-chamber MFCs consisted of an anode and cathode placed on opposite sides in a plastic (Plexiglas)cylindrical chamber 4cm long by 3cm in diameter (empty bed volume of 28mL)as previously reported (11).The anode electrode was made of toray carbon paper (without wet proofing;E-Tek).The cathode was carbon paper containing 0.35mg/cm 2Pt (E-Tek).Platinum wire was used to connect the circuit.Following inoculation and stable power generation using domestic wastewater (after four transfers of wastewater into the reactor,140h),a nutrient medium containing acetate or butyrate was added to the anode chamber.Acetate (80-800mg/L)and butyrate (75-1000mg/L)concentrations were varied to determine power output as a function of substrate concentration.No precautions were taken to remove dis-solved oxygen from the medium or to maintain anaerobic conditions in the anode chamber.Experiments were con-ducted at least in duplicate,in a constant-temperature room (30°C).Calculations.Voltage (V )was measured using a multi-meter with a data acquisition system (2700,Keithly)and used to calculate the power (P )according to P )IV.Power was normalized by either the cross-sectional area (projected)of the anode,A ,or by the liquid volume,v .The Coulombic efficiency was calculated as,E )C p /C Ti ×100%,where C p,is the total coulombs calculated by integrating the current over time.C Ti is the theoretical amount of coulombs that can be produced from either sodium acetate (i )a )or sodium butyrate (i )b ),calculated aswhere F is Faraday’s constant (96485C/mol ‚electrons),b i the number of moles of electrons produced per mole of substrate (b a )8,b b )20),S i the substrate concentration,and M i the molecular weight of the substrate (M a )82,M b )110).Overall energy recovery was calculated as,E E )E p /E Ti ×100%,where E p (J),is the total energy calculated by integrating the power over time.E Ti (J)is the theoretical amount of energy that can be produced from the substrate,calculated aswhere ∆H is the enthalpy change of the following reaction under standard conditions:Power was modeled as a function of substrate concentra-tion (S )using an empirical Monod-type equation asP max the maximum power and K s the half-saturation constant were determined using the Solver function in Microsoft Excel 2002.Analysis.Acetate and butyrate concentrations were analyzed using a gas chromatograph (Agilent,6890)equipped with a flame ionization detector and a 30m ×0.32mm ×0.5µm DB-FFAP fused-silica capillary column followed the same procedure described previously (11).Electrode open circuit potentials (OCP)and working potentials were mea-sured using a multimeter (83III,Fluke)with Ag/AgCl reference electrode (RE-5B,Bioanalytical Systems).Cyclic Voltammetry (CV).Cyclic voltammetry (PC 4/750potentiostat,Gamry)was used to characterize the oxidation -reduction reactions on the electrode surface by measuring the current response at an electrode surface to a specific range of potentials in an unstirred solution at a scan rate of 20mV/s (minimum of 5scans).The anode was the working electrode,and the counter electrode was the MFC cathode with a Ag/AgCl reference electrode.The potentials were originally in the range of -800to 200mV,but since peaks were only found in the range of -500to 0mV,this smaller range was used in the latter experiments.ResultsPower Generation as a Function of Substrate Concentra-tion.Following inoculation and stable power generation of the reactor with wastewater,a stable voltage was generated after three additional transfers (∼60h)using a medium containing acetate (80mg/L)or butyrate (75mg/L)into the anode chamber.An example of the cycle of power generation for reactors fed different initial acetate concentrations (80-800mg/L)is shown in Figure 1.A plot of the maximum power output at each initial substrate concentration demonstrated saturation kinetics at three different circuit loads of 218,1000,and 5000Ω(Figure 2A).A maximum power density of P max )661mW/m 2and half-saturation constant of K s )141mg/L (R 2)0.997)was obtained using a 218Ωresistor,while those using 1000and 5000Ωresistors were P max )343mW/m 2and K s )43mg/L (R 2)0.999)and P max )86mW/m 2and K s )9mg/L (R 2)0.999),respectively.For the butyrate-fed MFC and a 1000Ωresistor,the maximum power was ap-proximately the same with P max )349mW/m 2and a half-saturation constant of K s )93mg/L (R 2)0.887)(Figure 2B).Power as a Function of Current Density.By varying the circuit resistance from 70to 5000Ω(current densities of 0.2-2.2A/m 2)with acetate (800mg/L)as the substrate,a maximum power of 506mW/m 2(12.7mW/L)was obtained at a current density of 1.8A/m 2(218Ω)(Figure 3).The MFC using butyrate (1000mg/L)as substrate generated a maxi-mum power of 305mW/m 2(7.6mW/L)at a current density of 0.65A/m 2(1000Ω).Electrode Potential.Electrode open circuit potentials and working potentials were measured for each substrate by varying the circuit load.With acetate (800mg/L)as the substrate,the anode and cathode open circuit potentials were -480(15and 318(10mV (Ag/AgCl reference electrode),C Ti )Fb i S i v /M i(1)E Ti )∆HS i v /M i(2)C 2H 4O 2+2O 2f 2CO 2(g)+2H 2O (l)(3)C 4H 8O 2+5O 2f 4CO 2(g)+4H 2O (l)(4)P )P max S /(K s +S )(5)FIGURE 1.Voltages generated using acetate at different concentra-tions.VOL.39,NO.2,2005/ENVIRONMENTAL SCIENCE &TECHNOLOGY9659respectively,with an OCP of 798mV (Figure 4).Similar results were obtained using butyrate (800mg/L),with an anode potential of -475(15mV,a cathode potential of 319(10mV,and an OCP of 794mV.The cathode exhibited an overpotential for both acetate and butyrate,with the voltage decreasing sharply from the open circuit potential to 105mV for acetate and 130mV for butyrate.For both substrates,the anode working potential increased slightly with current density at the lower current density (0-1.8A/m 2for acetate and 0-0.66A/m 2for butyrate),but it became unstable at a higher current (over 2.2A/m 2for acetate and 0.77A/m 2for butyrate)(Figure 4).At the lower current density,current densities were limited by high resistance.At a lower circuit resistance (<218Ωfor acetate and <1000Ωfor butyrate),the bacteria growing on the anode were unable to transfer electrons fast enough into the circuitcausing an increased overpotential.Acetate sustained a higher current density that was 3times that measured for butyrate (2.2versus 0.77A/m 2),indicating faster bacterial uptake of acetate than butyrate.Substrate Degradation and Coulombic Recovery.Sub-strate removal was nearly complete (>99%removal for acetate,>98%for butyrate)when the voltage of the batch experiments (1000Ω)was reduced to <0.030V for all tests at different initial substrate concentrations.The overall Coulombic efficiency was a function of substrate concentra-tion and circuit resistance.Coulombic efficiency decreased from 28.3to 13.2%when the acetate concentration increased from 80to 800mg/L (1000Ω)(Figure 5).At a fixed initial acetate concentration (800mg/L),decreasing the circuit resistance from 5000to 70Ωincreased Coulombic efficiency from 9.9to 31.4%(Figure 6).The Coulombic efficiencies with butyrate were lower than those of acetate,but decreased (15-7.8%)with increased concentrations of butyrate (75-1000mg/L).In tests with butyrate,low concentrations of acetate (<50mg/L)were detected in solution,indicating that some butyrate was degraded into acetate.Electricity could have been generated from butyrate degradation to acetate ac-cording toAlternatively,it is possible that butyrate was first converted into acetate by butyrate-degrading acetogenic bacteria (23).Energy Recovery.While Coulombic efficiency indicates recovery of electrons,the overall energy recovery of the system represents the energy harvested as electricity from bacteria versus that lost to other processes.When acetate was used,6.5-5.1%of the energy was recovered at initial acetate concentrations of 80-800mg/L.Energy recovery was in-creased from 3.0to 7.2%by increasing circuit resistance (from 70to 218Ω)for lower circuit loads.Increasing the resistance further to 5000Ωin acetate-fed cells decreased the overall energy recovery to 4.7%.In butyrate-fed MFC tests,energy recovery ranged from 2to 5%.Cyclic Voltammograms.Extracellular electron transfer in mediator-less MFCs can occur by two mechanisms:byFIGURE 2.Maximum power density as a function of (A)initial acetate concentration using different resistors and (B)initial butyrate concentration using a 1000Ωresistor.(Error bars (SD based on the maximum voltages in experiments run intriplicate.)FIGURE 3.Power density as a function of currentdensity.FIGURE 4.Anode and cathode potential (vs Ag/AgCl reference electrode;195mV vs NHE)as a function of currentdensity.FIGURE 5.Coulombic and energy recoveries as a function initial acetate concentration (1000Ω).FIGURE 6.Coulombic and energy recoveries as a function of circuit resistance (800mg/L acetate).C 4H 8O 2+2H 2O f 4C 2H 4O 2+4H ++4e -(6)6609ENVIRONMENTAL SCIENCE &TECHNOLOGY /VOL.39,NO.2,2005membrane-bound proteins,mediators,or electron shuttles,produced by the bacteria and excreted into the environment (12,24).To examine whether electron shuttles were generated and contributed to the electricity generation in this system,CV was performed using three samples:anodes obtained from a MFC during stable power generation;anodes at the end of a cycle of electricity generation (when the substrate was consumed);and a new anode (no biofilm)present in the same medium used in other tests.Using anodes from active MFCs,oxidation peaks in the forward scans of the voltammograms were observed at -280mV (vs Ag/AgCl)(1100µA)for the acetate-fed MFC and -300mV (343µA)for the butyrate-fed MFC (Figure 7).During the reverse scan,additional oxidation peaks were found at -340mV (vs Ag/AgCl)(608µA)for acetate and -370mV (vs Ag/AgCl)(190µA)for butyrate.No reduction peaks were found in reverse scans.However,two redox couples were observed in voltammograms (-304and -377mV)using anodes obtained at the end of the batch electricity generation cycle (2mV,1000Ω)(Figure 8A).This could be evidence of mediator production by the mixed culture.However,based on the low current of 50-150µA,the concentration of mediators would be quite low.These mediators,if present,were held in the biofilm.When a voltammogram was obtained using the same solution,but with a new anode (no biofilm),no redox couples were detected (Figure 8B).These results make it appear likely that the main mechanism of power production in these batch tests was by direct transfer of electrons to the electrode by bacteria containing enzymes directly attached to their cell membranes.DiscussionThe electricity generation from either acetate or butyrate using a single-chamber MFC is a proof-of-concept demon-stration of a technology to link MFCs with biohydrogen production by fermentation.Biochemical routes that lead to acetate produce more hydrogen than those that lead to butyrate production.It was shown here that the power generated from MFCs fed acetate (506mW/m 2or 12.7mW/L)was up to 66%higher than those fed with butyrate (305mW/m 2or 7.6mW/L).The predominant oxidation peak intensity of CV also reflected the electron-transfer rate difference from acetate and butyrate to electrodes with the maximum current reached 1100µA for the acetate-fed anodebut only 343µA for the butyrate-fed one.Taken together,these results demonstrate that acetate is a preferred aqueous substrate for both hydrogen production and electricity generation in MFCs.The power generated here by using a direct-air cathode MFC without a PEM was over 54%(acetate)and 57%(butyrate)higher than power levels obtained using a MFC in the presence of the PEM (328mW/m 2with acetate;194mW/m 2with butyrate).This greater level of power generation in the absence of a PEM was previously reported in tests using glucose or domestic wastewater as substrates (11).By removing the PEM in those studies,power output was 5.2(wastewater)and 1.9times greater (glucose)than power levels obtained in MFCs containing a PEM.Since PEMs such as Nafion are quite expensive,the removal of PEM greatly decreases the cost for MFC construction and thus further increases the possibility of economical power generation in MFCs linked with hydrogen production.Further Improvements Needed in MFC Performance.One aspect that needs to be improved in MFC performance is power density.Based on available anode surface area and maximum bacterial growth rates,the maximum power that can be produced in a mediator-less MFC was estimated on the order of 103mW/m 2by assuming a monolayer of bacteria on an electrode surface (11).However,the presence of additional bacteria in a biofilm capable of producing media-tors could greatly increase power.The potential of large increases in power production using bacteria that produce their own mediators was demonstrated by Rabaey et al.(12).They obtained a power density of 4310mW/m 2using a mixed culture primarily consisting of A.faecalis ,E.faecium ,and P.aeruginosa.The use of cyclic voltammograms in their study demonstrated that power production occurred primarily as a result of mediators,in contrast to our study which shows that mediators were largely absent.Long-term enrichment and cultivation of bacteria in MFCs could lead to increased power production if mediators remain in the system.In our tests,we found some evidence of mediator production by the biofilm but did not observe mediators in solution.Thus,the contribution of exogenous mediators to MFCs,particu-FIGURE 7.Cyclic voltammograms of the anode of an (A)acetate-fed and (B)butyrate-fed MFC (the anode chamber solution contained medium and thesubstrate).FIGURE 8.Cyclic voltammograms of (A)the anode with a biofilm and (B)a new anode (no biofilm).(Both tests were conducted with the anodes placed in the solution obtained from the anode chamber of an acetate-fed MFC at the end of a batch test).VOL.39,NO.2,2005/ENVIRONMENTAL SCIENCE &TECHNOLOGY9661larly in continuous-flow systems where they could diffuse out of the system,is unknown.The other aspect of MFC operation that needs to be improved is Coulombic efficiency and overall energy recovery. The Coulombic efficiency of the air-cathode MFC withouta PEM used in this study was10-30%.This was greater than0.04%reported for starch processing wastewater(19)but comparable to3-12%found for domestic wastewater(22). However,these values are substantially lower than89% reported by Rabaey et al.(25)using glucose as substrate.In their system using an enriched culture,potassium hexacy-anoferrate was used as oxidant instead of oxygen,and a PEM was used to separate the anode and cathode chambers. Energy recovery in their system was65%versus only2-7% obtained here with a nonenriched inoculum.There are several factors that could be responsible for low electron and energy recoveries in MFCs used here.First, removal of the PEM increases oxygen transfer into the anode chamber.Oxygen diffusion through the cathode could account for21-50%of acetate loss based on a previously measured oxygen-transfer rate of0.187mg/h(11).Second, substrate loss is also possible due to methanogenesis.The high concentrations of acetate and anaerobic conditions favor methane production in the anode chamber.Third,substrate is used for bacterial growth and production of biomass.It may be that the bacteria grown in our MFC tests have higher biomass yields than other bacteria such as Geobacter ed in pure culture studies(16).Fourth,alternate electron acceptors,such as sulfate present in the medium,can also reduce electron recovery.Energy recovery relies on all the same factors as electron recovery,but additionally depends on the energy used by the bacteria versus that available to drive electron flow.The sooner electrons are transferred from enzymes in the bacterial respiratory pathway(i.e.,at the level of a quinone versus that of a cytochrome),the greater the potential and the larger the energy recovery.To increase electron and energy recovery,oxygen diffusion must be reduced from the cathode into the anode chamber. This could be achieved by further increases in the cathode efficiency making it possible to use smaller cathodes. Alternatively,coatings could be placed on the cathode that restrict oxygen diffusion by allow for proton transfer to the cathode.It may be possible to limit methanogenesis by controlling pH or through treatment of the inoculum to reduce the potential for methanogen growth.Further ad-vances in the design and operation of MFC are needed in order to accomplish greater overall MFC performance. AcknowledgmentsThis research was supported National Science Foundation Grants BES-0331824and BES-0124674,a seed grant from The Huck Institutes of the Life Sciences at Penn State,and the Stan and Flora Kappe endowment.Literature Cited(1)M.E.Watanabe Consulting Inc.In Research Needs to OptimizeWastewater Resource Utilization;Watanabe,M.E.,Ed.;Water Environment Research Foundation(WERF):New York,1999.(2)Logan,B.E.Feature Article:Biologically extracting energy fromwastewater:biohydrogen production and microbial fuel cells.Environ.Sci.Technol.2004,38,160A-167A.(3)Lay,J.J.;Lee,Y.J.;Noike,T.Feasibility of biological hydrogenproduction from organic fraction of municipal solid waste.Water Res.1999,33,2579-2586.(4)Fang,H.H.P.;Liu,H.Effect of pH on hydrogen productionfrom glucose by a mixed culture.Bioresour.Technol.2002,82, 87-93.(5)Logan,B.E.;Oh,S.E.;Kim,I.S.;Van Ginkel,S.Biologicalhydrogen production measured in batch anaerobic respirom-eters.Environ.Sci.Technol.2002,36,2530-2535.(6)Liu,H.;Fang,H.H.P.Hydrogen production from wastewaterby acidogenic granular sludge.Water Sci.Technol.2002,17(1), 153-158.(7)Liu,H.;Zhang,T.;Fang,H.H.P.Thermophilic H2productionfrom a cellulose-containing wastewater.Biotechnol.Lett.2003, 25,365-369.(8)Fang,H.H.P.;Liu,H.;Zhang,T.Characterization of a hydrogen-producing granular sludge.Biotechnol.Bioeng.2002,78,44-52.(9)Miyake,J.;Masato,M.;Yasuo,A.Biotechnological hydrogenproduction:research for efficient light energy conversion.J.Biotechnol.1999,70,89-101.(10)Zhang,T.;Liu,H.;Fang,H.H.P.Microbial Analysis of aPhototrophic Sludge Producing Hydrogen from Acidified Waste-water.Biotechnol.Lett.2002,24,1833-1837.(11)Liu,H.;Logan,B.E.Electricity generation using an air-cathodesingle chamber microbial fuel cell in the presence and absence of a proton exchange membrane.Environ.Sci.Technol.2004, 38,4040-4046.(12)Rabaey,K.;Boon,N.;Siciliano,S.D.;Verhaege,M.;Verstraete,W.Biofuel cells select for microbial consortia that self-mediate electron transfer.Appl.Environ.Microbial.2004,70,5373-5382.(13)Bond,D.R.;Holmes,D.E.;Tender,L.M.;Lovley,D.R.Electrode-reducing microorganisms that harvest energy from marine sediments.Science2002,295,483-485.(14)Reimers,C.E.;Tender,L.M.;Ferig,S.;Wang,W.Harvestingenergy from the marine sediment-water interface.Environ.Sci.Technol.2001,35,192-195.(15)Pham,C.A.;Jung,S.J.;Phung,N.T.;Lee,J.;Chang,I.S.;Kim,B.H.;Yi,H.;Chun,J.A novel electrochemically active and Fe-(III)-reducing bacterium phylogenetically related to Aeromonas hydrophila,isolated from a microbial fuel cell.FEMS Microbiol.Lett.2003,223,129-134.(16)Bond,D.R.;Lovely,D.R.Electricity production by Geobactersulfurreducens attached to electrodes.Appl.Environ.Microbiol.2003,69,1548-1555.(17)Kim,B.H.;Park,D.H.;Shin,P.K.;Chang,I.S.;Kim,H.J.Mediator-less biofuel cell.U.S.Patent5976719,1999.(18)Kim,H.J.;Park,H.S.;Hyun,M.S.;Chang,I.S.;Kim,M.;Kim,B.H.A mediator-less microbial fuel cell using a metal reducingbacterium,Shewanella putrefacians.Enzyme Microbiol.Technol.2002,30,145-152.(19)Park,H.S.;Kim,B.H.;Kim,H.S.;Kim,H.J.;Kim,G.T.;Kim,M.;Chang,I.S.;Park,Y.K.;Chang,H.I.A novel electro-chemically active and Fe(III)-reducing bacterium phylogeneti-cally related to Clostridium butyricum isolated from a microbial fuel cell.Anaerobe2001,7,297-306.(20)Chaudhuri,S.K.;Lovley,D.R.Electricity generation by directoxidation of glucose in mediatorless microbial fuel cells.Nat.Biotechnol.2003,21,1229-1232.(21)Park,D.H.;Zeikus,J.G.Improved fuel cell and electrode designsfor producing electricity from microbial degradation.Biotechnol.Bioeng.2003,81(3),348-355.(22)Liu,H.;Ramnarayanan,R.;Logan,B.E.Production of electricityduring wastewater treatment using a single chamber microbial fuel cell.Environ.Sci.Technol.2004,38,2281-2285.(23)Anderson,K.L.;Tayne,T.A.;Ward,D.M.Formation and fateof fermentation products in hot spring cyanobacterial mats.Appl.Environ.Microbiol.1987,53,2343-2352.(24)Hernandez,M.E.;Newman,D.K.Extracellular electron transfer.CMLS,Cell Mol.Life Sci.2001,58,1562-1571.(25)Rabaey,K.;Lissens,G.;Siciliano,S.D.;Verstraete,W.A microbialfuel cell capable of converting glucose to electricity at high rate and efficiency.Biotechnol.Lett.2003,25,1531-1535. Received for review July12,2004.Revised manuscript re-ceived October13,2004.Accepted October19,2004.ES048927C6629ENVIRONMENTAL SCIENCE&TECHNOLOGY/VOL.39,NO.2,2005。

微生物燃料电池(1)全解

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2 .加入其他催化剂
Qiao等报道了用碳纳米管/ 聚苯胺(CNT/ PANI)作为MFC 阳极。 Kargi 等用铜和铜- 金导线来代替石墨电极作为MFC 的阳极,结果发现,随着阳极表面积的增大,产生的电流和功率也随之增大。 Rosenbaum等研究了用碳化钨作为微生物燃料电池的阳极,获得了不错的效果,其电化学活性和化学稳定性作为微生物燃料电池的阳极是适合的。

具有产电与废弃物处置的双重功效。微生物燃料电池代表了当今最前沿的废弃物资源化利用方向之一，其研究受到了学术界的极大关注，有望成为未来有机废弃物能源化处置的支柱性技术。
发展历史

1.早在1910年，英国植物学家马克·比特首次发现了细菌的培养液能够产生电流，于是，他用铂做电极，把它放进大肠杆菌和普通酵母菌培养液里，成功制造出了世界第一个微生物燃料电池； 2.1984年，美国制造了一种能在外太空使用的微生物燃料电池，它的燃料为宇航员的尿液和活细菌，不过它的放电率极低； 3.1991 年开始出现使用微生物燃料电池处理生活污水的范例，然而，直到最近几年用MFC处理生活污水得到的电池功率才有所增强； 4.近几年, MFC的研究已经成为治理和消除环境污染源, 开发新型能源研究工作者的关注热点。
阳极材料

阳极担负着微生物附着并传递电子的作用，可以说是决定 MFC产电能力的重要因素，同时也是研究微生物产电机理与电子传递机理的重要的辅助工具。现在，MFC阳极是微生物附着的主要场所，其量的多少直接目前对阳极的研究主要是关系到产电能力的大小，其必要条件是具有高导电率、高对导电材料的改性比表面积、高孔隙率、廉价易造且可回收等。主要是以碳为主要材料，包括碳纸、碳布、石墨棒、碳毡、泡沫石墨加入其他的催化剂以及碳纤维刷。

微生物燃料电池的发展现状与未来趋势分析

微生物燃料电池的发展现状与未来趋势分析一、引言微生物燃料电池作为一种新兴的绿色能源技术，吸引了广泛的研究兴趣。

它利用微生物的代谢活动将有机废物转化为电能，具有环境友好、可持续发展等多种优势。

本文将对微生物燃料电池的发展现状以及未来的发展趋势进行分析和展望。

二、微生物燃料电池的发展现状1. 技术原理和工作机制微生物燃料电池是一种将有机废物转化为电能的技术，其中微生物在阳极上进行氧化还原反应，释放出电子，而在阴极上，电子与氧气结合生成水。

这一技术原理能够为废物处理提供新的解决方案，并实现同时产生能源的效果。

2. 应用领域和商业化进展微生物燃料电池在废物处理、能源生产和环境修复等领域具有广泛的应用前景。

目前，已有一些微生物燃料电池产品投入市场，并取得了一定的商业化进展。

以废水处理为例，微生物燃料电池可以将有机物降解为无机物，从而实现废水的净化和能源的回收，为企业节约了处理成本。

三、微生物燃料电池的挑战与未来趋势1. 技术挑战微生物燃料电池目前仍面临着一些技术挑战，如电化学效率低、微生物耐受性差、实际应用环境不确定性等。

这些问题限制了微生物燃料电池的实际应用和规模化推广。

因此，需要通过针对性的研究和技术创新来解决这些挑战。

2. 发展趋势虽然微生物燃料电池面临着一些挑战，但其具有长期发展的潜力。

未来，微生物燃料电池有望在以下几个方面实现进一步的发展。

首先，技术创新将推动微生物燃料电池的发展。

通过改进阳极、阴极材料，提高电化学效率以及微生物对废物的降解效率等方面的研究，将有助于提升微生物燃料电池的性能。

其次，微生物燃料电池与其他能源技术的结合将加速其推广。

如将微生物燃料电池与太阳能、风能等进行组合应用，可以实现能源的多样化和综合利用，进一步提高能源利用效率。

再次，政策支持与市场需求将成为微生物燃料电池发展的重要驱动力。

随着环境保护和可持续能源的需求增加，政府对微生物燃料电池的支持力度将进一步增加，为其规模化应用和商业化发展提供有利条件。

微生物燃料电池的原理与应用

微生物燃料电池的原理与应用微生物燃料电池是一种利用微生物酵解产生的电子传递到电极上产生电力的技术，它的特点是能够将有机废弃物转化为电能，同时减少污染、降低能源成本，因此备受关注。

本文将讨论微生物燃料电池的原理与应用。

一、微生物燃料电池的原理微生物燃料电池的核心原理是将来自微生物代谢的电子传递到电极上来产生电力。

在微生物燃料电池中，微生物活性产生的氢离子（H+）和电子通过呼吸链途径转移到氧气或氧化的底物上，达到能量代谢的目的。

而当微生物呼吸链的末端正好是电极表面时，电子可以被导向电极表面形成电流，故而产生电力。

微生物燃料电池中的微生物可分为两类：一是光合微生物，如藻类和细菌等，其使用太阳能将二氧化碳和水转化为有机物进行代谢；二是好氧和厌氧微生物，如大肠杆菌等，其使用底物在代谢过程中产生的氢离子和电子转移到电极上形成电流。

于是，我们可以通过对不同类型的微生物进行研究和利用，来产生不同种类和强度的电流。

二、微生物燃料电池的应用微生物燃料电池由于具有高效、便捷和环保的优点，被广泛运用于生产和生活的多个领域。

以下就是微生物燃料电池的应用：1. 生物废弃物处理微生物燃料电池可以将厨余垃圾、污泥和废水等有机废弃物转化为电能，实现废物处理和能源回收的双重效果。

利用微生物燃料电池处理废弃物不仅能节约大量处理成本，而且可以减少对环境的污染。

2. 智能物联网微生物燃料电池可以产生小型电源，已经应用于智能物联网设备。

这些设备包括传感器、监控装置、移动通信设备和环境检测仪器等，都需要能够稳定供应电能，而微生物燃料电池可以为这些设备提供稳定的电源。

3. 医疗、军事和安全领域微生物燃料电池还可以应用于一些不便使用电网的场合，如医疗方面的义肢、覆盖物和人造耳蜗，军事方面的夜视仪、无人机和常规电力供应等，安全领域的消防器材、探矿工具和遥控钻机等，都可以通过微生物燃料电池进行供电。

三、微生物燃料电池的未来发展随着科技的不断进步，微生物燃料电池在未来的发展前景非常广阔。

微生物燃料电池

微生物燃料电池1.引言能源紧张和环境污染是可持续发展面临的重大挑战。

经济发展的同时，能源消耗也在急剧增长，而现有的化石能源消耗则带来了环境质量的不断恶化。

寻找新型能源，实现经济、社会和环境的可持续发展是当今社会的主要研究问题。

清洁能源的发展则成为解决问题的关键。

与此同时，不断发展的生物燃料电池成为了人们关注的焦点。

微生物燃料电池的兴起为可再生能源的生产和废弃物的处理开辟了新途径。

首先，微生物电池的燃料来源比较多样化，如多种有机无机材料，甚至能够直接利用废液、废物作为原料产生电能，净化环境。

其次，微生物燃料电池能够实现无污染、零排放、无需能量输入，满足环境友好型电池的需求。

此外，微生物燃料电池的能量转化效率非常高，可以发展成长效、低廉的能量系统；加上其操作条件是在常温常压的温和条件下工作，实现了电池的低维护成本和高安全性[1]。

微生物燃料电池的发展历史中，经历了几次重大进步。

1911年Potter用酵母和大肠杆菌进行实验，首次实现了微生物产电，从此开启了微生物燃料电池发展的道路[2]。

20世纪80年代，细菌发电取得重大进步，随后微生物燃料电池的输出功率也有了较大的提高，其作为小功率电源使用的实际应用也进一步成为可能。

2002年以后，微生物燃料电池的研究更是进入了飞速发展阶段，研究人员不仅发明了无需电子传递中间体的燃料电池，也在降低内阻、功率输出、优化结构和降低成本等方面都取得了重大进步。

近年来，微生物燃料电池的应用领域也更加宽泛。

2.微生物燃料电池的原理微生物燃料电池是一种利用微生物进行能量转换，把呼吸作用产生的电子传递到电极上的装置，能够通过产电菌代谢可生物降解的有机物，并将代谢产生的电子传递到外电路输出电能。

原理如图1所示[3]。

微生物燃料电池中，氧化底物的细菌通常在厌氧条件下将电子通过电子传递中介体或者细菌自身的纳米导线传递给阳极，电子通过连接阴阳两极的导线传递给阴极，而质子通过隔开两极的质子交换膜(Proton exchange membrane, PEM)到达阴极，在含铂的阴极催化下与电路传回的电子和O2反应生成水[4]。

微生物燃料电池

微生物燃料电池骆沁沁20914133摘要：微生物燃料电池以微生物作为催化剂，直接把化学能转化为电能，具有燃料来源广泛、反应条件温和、生物相容性好等优点。

本文简述了微生物燃料电池的工作原理及其最新的研究进展：主要是无介体微生物燃料电池的研究和高活性微生物的选用。

最后对微生物燃料电池的发展方向作出展望。

关键词：微生物燃料电池原理研究进展Abstract: Microbial fuel cell is a device converting chemical energy into ele ctrical energy directly with the microbial-catalysts, which has the advantages of abundant fuel resource, mild reaction and good biology consistence. After the principles of microbial fuel cell introduced briefly, the research progress was reviewed. Researching mediator-less microbial fuel cell and high-activity microbial are the new direction in the study of microbial fuel cell. At last, the prospects of microbial fuel cell were described.Key words: microbial fuel cell, principles, the research progress1 前言近些年来，化石燃料（煤、天然气、石油）的使用量逐年大量递增，据国内外学者统计，化石燃料的储备量仅能提供全球未来250年的能源使用，这引起了全球性的能源危机。

微生物燃料电池原理与应用

微生物燃料电池原理与应用微生物燃料电池(Microbial Fuel Cell, MFC)是一种利用微生物氧化有机物产生电能的装置。

它基于微生物的电化学反应来产生电力，将化学能直接转化为电能。

微生物燃料电池的原理是通过利用微生物的代谢作用将有机废物（如人类粪便、废水等）中的化学能转化为电能，实现能量回收和减少污染物的排放。

该技术有着巨大的潜力，能够广泛应用于废水处理、能源生产和环境保护等领域。

微生物燃料电池中的关键组成部分是阳极和阴极。

阳极是微生物活动的场所，它提供了一个良好的电子传递通道。

通常情况下，阳极材料是由导电性好的物质构成，如碳纳米管、碳纳米颗粒等。

阴极则是电子和氧气进行还原反应的场所，它常常使用氧化剂（如氧气或氯离子）来参与电子转移反应。

阳极和阴极之间的电子传递通过外部电路完成，从而产生电能。

微生物燃料电池的关键是利用微生物的代谢作用。

在阳极的表面，微生物通过氧化有机物来产生电子和质子。

微生物中的电子经过阳极材料传递到外部电路中去，形成电流。

同时，微生物释放质子到电解质中去。

质子在电解质中通过离子交换膜传递到阴极处与氧气结合，还原发生的氧化反应，并接受电子，形成水。

这个过程实际上是微生物通过氧化有机物来释放能量，将化学能转化为电能。

这个电能可以直接用来驱动负载，如电灯、泵浦等。

微生物燃料电池的应用非常广泛。

一方面，它可以作为一种有效的废水处理技术。

通过将微生物燃料电池应用于废水处理厂，可以不仅处理废水中的有机物，还能够产生电能。

这就在一定程度上实现了能源回收和环境保护的双重效果。

另一方面，微生物燃料电池还可以应用于能源生产。

有机废物广泛存在于农村、城市和工业生产中，通过利用微生物燃料电池来转化这些有机废物为电能，可成为一种可再生能源来源。

此外，微生物燃料电池还可以应用于生物传感器和无源传感器等领域。

尽管微生物燃料电池具有广泛的应用前景，但目前仍然有一些挑战需要克服。

首先，阳极材料的选择和优化对微生物燃料电池的性能至关重要。

微生物燃料电池

微生物燃料电池摘要：微生物燃料电池的研究集中于产电细菌、电极材料和电池反应器构型等方面,同时,微生物燃料电池在废水处理、生物修复等方面具有广阔的应用前景。

本文介绍了微生物燃料电池的原理、影响微生物燃料电池的因素及近几年微生物燃料电池在环境污染治理中的研究进展。

关键词：微生物燃料电池双室质子交换膜微生物燃料电池（Microbial Fuel Cell, MFC）是利用微生物的催化作用将废弃物中碳水化合物的化学能转化为电能的一种装置[1]。

MFC 是一种清洁能源，符合循环经济、清洁生产和可持续发展的要求。

随着微生物、电化学及材料等学科的发展，MFC 的结构和性能不断改善[2]，逐步向环境领域扩展。

MFC的构造在双室[3]的基础上出现了单室[4]及升流式MFC[5]，底物由单一小分子有机物，如醋酸钠[3]、葡萄糖[4]，转向大分子混合有机物，如氯酚废水[6]、秸秆废水[7]、啤酒废水[8]等。

本文对MFC的工作原理、构造态进行了讨论，对提高MFC性能的途径和方法进行了整合。

1MFC工作原理及结构1.1MFC工作原理微生物燃料电池以附着于阳极的微生物作为催化剂,降解有机物(葡萄糖、乳酸盐和醋酸盐等) 产生电子和质子。

产生的电子传递到阳极,经外电路到达阴极,由此产生外电流;产生的质子通过分隔材料(质子交换膜(PEM) 或盐桥) 或直接通过电解液到达阴极,在阴极与电子、氧化物(铁氰化钾、氧气等) 发生还原反应,从而完成电池内部电荷的传递[9]。

而MFC另外一个重要的过程就是电子的转移(图1)[10]。

目前学术界普遍接受的观点有三种：（1）细胞膜：该机理认为，生长在电极表面的细菌只有将细胞膜接触到电极的表面，代谢过程产生的电子才能通过细胞膜中的细胞色素传导到电极上[11]。

有机物在细菌体内代谢，通过同化作用生成细胞体，异化作用生成CO2，释放的电子通过细胞色素传导到电极表面。

直接电子转移需要微生物拥有膜连接电子运输蛋白质中间体，这种中间体能够将电子从细胞内部转移到外部，进而达到固态电子受体表面。

微生物燃料电池存在的问题

微生物燃料电池存在的问题
微生物燃料电池是一种利用微生物将有机物质转化为电能的新
型生物电化学系统。

虽然这种技术具有许多优势，如高效、低成本、环保等，但是在实际应用中还存在一些问题。

首先，微生物燃料电池的发电效率较低。

目前市场上的微生物燃料电池的发电效率只有10%左右，远低于传统化石能源发电设备的效率，这也限制了其在实际应用中的推广和应用。

其次，微生物燃料电池的稳定性较差。

微生物燃料电池的电化学反应过程是一个复杂的生物化学过程，微生物的生长状态、环境参数的变化等因素都会影响其发电效率和稳定性，这也是目前微生物燃料电池技术面临的主要挑战之一。

此外，在微生物燃料电池的应用过程中，还存在一些技术难题，如微生物生长速度慢、电极寿命短、电极材料选择不当等问题。

这些问题不仅限制了微生物燃料电池的发展，同时也限制了其在工业生产中的应用。

综上所述，微生物燃料电池技术在实际应用中还存在一些问题，需要进一步的技术研究和发展。

只有克服这些问题，才能更好地发挥微生物燃料电池在环保、节能等方面的优势。

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单室微生物燃料电池
单室微生物燃料电池是一种新型的电池技术，它能够利用微生物通过普通有机物质代谢释放的电子来产生电力，因此被广泛应用于能源领域以及一些环境相关的应用中。

1. 单室微生物燃料电池的原理
单室微生物燃料电池是一种基于微生物代谢产生电子的技术，因此它的原理比较简单。

在单室微生物燃料电池中，我们通常会将一种有机物质（如葡萄糖）注入到电池室中，然后微生物（如电化学活性细菌）会利用这些有机物质进行代谢，产生一些中间产物，其中一些产物会释放出电子，这些电子可以通过电解质和电极传递到电池的另一端，从而产生电流。

2. 单室微生物燃料电池的应用
单室微生物燃料电池的应用非常广泛。

首先，它可以用来提供电力。

由于单室微生物燃料电池不需要任何外部能源，因此在一些缺乏电力的地区可以被当作一种补充电源来使用。

例如，在一些山区、岛屿或极地地区等偏远地区，单室微生物燃料电池可以提供一定的电力供应，为当地民众生活、交通、通讯等提供方便。

除此之外，单室微生物燃料电池还可以被应用于污水处理、污染物降解等环境领域。

由于微生物在代谢有机物质的过程中可以释放出电子，并且这些代谢过程是相对稳定和可控的，因此单室微生物燃料电池可以被应用于污水处理、废水处理等领域，从而实现有机物质（如废水中的有机物）对能源的转化。

此外，单室微生物燃料电池还可以被用来净化土壤、降解空气中的有害物质等。

3. 单室微生物燃料电池的优缺点
单室微生物燃料电池的优点主要包括以下几个方面：
（1）电化学反应稳定可控，电能转换效率高。

（2）微生物代谢产生的电子可通过电极转变为电能，无需使用化石燃料、化学电池等。

（3）单室微生物燃料电池生产的电能可以直接用于地下、水下等特殊地点。

（4）单室微生物燃料电池在应用于污水处理、污染物降解等环境领域的同时，还可以产生能量。

然而，单室微生物燃料电池也存在一些缺点：
（1）相关研究尚处于初步阶段，尚未形成完整的商业应用。

（2）单室微生物燃料电池的效率仍有待提高，需要进一步研究深入探究小肠细菌电压谷、阳离子交换膜等关键性问题。

（3）单室微生物燃料电池的生产难度较大，制造成本较高。

（4）单室微生物燃料电池工作稳定性尚待进一步提升，容易在微生物自然死亡、沉积物打扰等情况下受到干扰，从而导致电池性能下降。

4. 单室微生物燃料电池发展趋势
总的来说，单室微生物燃料电池具有广阔的发展前景。

在不断推进绿色能源发展的今天，单室微生物燃料电池作为可再生能源的代表之一，其应用前景广阔，被广泛应用于能源、环保等领域。

未来，单室微生物燃料电池的发展趋势可能包括以下几个方面：
（1）技术不断升级。

技术上的不断改进将会使单室微生物燃料电池的发电效率得到更好的提高，性能更稳定，使用寿命更长。

（2）应用领域扩大。

单室微生物燃料电池将更加广泛地应用于环保、新能源等领域，如土壤和水体处理、生物传感等领域。

（3）多品种、多元化发展。

单室微生物燃料电池将不断推进其多样化的发展，包括开发出新型微生物细胞、新型催化剂等，以满足不同领域的需求。

总之，单室微生物燃料电池作为一种新型、智能的技术，其应用前景广阔。

未来，我们希望在单室微生物燃料电池技术的不断发展中，能够创造更多的应用价值，让它成为能源领域的绿色佼佼者。