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1.
阳极作为微生物燃料电池中的重要组成部分,其性能的高低显著影响着微生物燃料电池的产电性能。纳米材料具有导电性好、表面积大等优良特性。因此,纳米材料修饰阳极能够有效减小电极内阻、增大微生物的粘附量,从而显著提高微生物燃料电池的产电性能。本文首先简要介绍了微生物燃料电池中阳极修饰纳米材料的种类,然后重点归纳了不同纳米材料修饰阳极对微生物燃料电池产电性能的影响及其原因。最后对微生物燃料电池阳极修饰纳米材料和技术进行展望。 相似文献
2.
Velasquez-Orta SB Yu E Katuri KP Head IM Curtis TP Scott K 《Applied microbiology and biotechnology》2011,90(2):789-798
This study determined the influence of substrate degradation on power generation in microbial fuel cells (MFCs) and microbial
community selection on the anode. Air cathode MFCs were fed synthetic medium containing different substrates (acetate, glucose
and starch) using primary clarifier sewage as source of electroactive bacteria. The complexity of the substrate affected the
MFC performance both for power generation and COD removal. Power output decreased with an increase in substrate complexity
from 99 ± 2 mW m−2 for acetate to 4 ± 2 mW m−2 for starch. The organic matter removal and coulombic efficiency (CE) of MFCs with acetate and glucose (82% of COD removal
and 26% CE) were greater than MFCs using starch (60% of COD removal and 19% of CE). The combined hydrolysis–fermentation rate
obtained (0.0024 h−1) was considerably lower than the fermentation rate (0.018 h−1), indicating that hydrolysis of complex compounds limits current output over fermentation. Statistical analysis of microbial
community fingerprints, developed on the anode, showed that microbial communities were enriched according to the type of substrate
used. Microbial communities producing high power outputs (fed acetate) clustered separately from bacterial communities producing
low power outputs (fed complex compounds). 相似文献
3.
Uptake rates of nitrogen and phosphorus in the water by Eichhornia crassipes and Salvinia auriculata
The main goal of this research was to survey information about the physiology of Eichhornia crassipes and Salvinia auriculata and their capacity to remove nitrogen and phosphorus from the environment, after quantifying the concentrations of the nitrogen (NO3-N, NH4-N and total-N) and phosphorus (PO4-P and total-P) compounds in the water. The macrophytes were incubated in the laboratory in plastic vials of approximately 1.5 litters containing a previously prepared solution of NH4NO3, NH4Cl and KH2PO4. Eichhornia crassipes exhibited the highest rates of nutrient reduction and the concentrations of NO3-N, NH4-N and PO4-P in the water influenced the uptake rates of nitrogen and phosphorus of the E. crassipes and S. auriculata. This information can help to reach adequate management strategies for aquatic macrophytes in order to reduce the eutrophication process in Imboassica lagoon. 相似文献
4.
Four microbial fuel cells (MFCs) inoculated with different bacterial species were constructed. The species were Pseudomonas putida, Comamonas testosteroni, Corynebacterium gultamicum, and Arthrobacter polychromogenes. The MFCs were operated under identical continuous flow conditions. The factors affecting the capabilities of the MFCs for
treating organic matter and generating power were evaluated and compared. The factors include microbial species type, organic
loading, and substrate degradation rate. For all four MFCs, power output increased with the organic loading rate. Power density
also increased with the substrate degradation rate. These findings implied that more organic matter was utilized for power
generation at higher organic loading and substrate degradation rates. However, coulombic efficiency increased with decreased
organic loading and substrate degradation rates. Apparently, all four MFCs had low efficiencies in generating power from organic
matter. These low efficiencies are attributed to the long distance between the anode and the cathode, as well as to the small
ratio of the proton exchange membrane surface area to the anode chamber surface area. These features may have caused most
of the protons produced in the anode chamber to leave the chamber with the effluent, which led to the low power generation
performance of the MFCs. 相似文献
5.
The significance of the initiation process parameters and reactor design for maximizing the efficiency of microbial fuel cells 总被引:1,自引:0,他引:1
Guotao Sun Anders Thygesen Marcel Tutor Ale Moses Mensah Finn Willy Poulsen Anne S. Meyer 《Applied microbiology and biotechnology》2014,98(6):2415-2427
Microbial fuel cells (MFCs) can be used for electricity generation via bioconversion of wastewater and organic waste substrates. MFCs also hold potential for production of certain chemicals, such as H2 and H2O2. The studies of electricity generation in MFCs have mainly focused on the microbial community formation, substrate effect on the anode reaction, and the cathode’s catalytic properties. To improve the performance of MFCs, the initiation process requires more investigation because of its significant effect on the anodic biofilm formation. This review explores the factors which affect the initiation process, including inoculum, substrate, and reactor configuration. The key messages are that optimal performance of MFCs for electricity production requires (1) understanding of the electrogenic bacterial biofilm formation, (2) proper substrates at the initiation stage, (3) focus on operational conditions affecting initial biofilm formation, and (4) attention to the reactor configuration. 相似文献
6.
Li ZhuangShungui Zhou Yong YuanTinglin Liu Zhifeng WuJiong Cheng 《Bioresource technology》2011,102(1):284-289
This study described an Enterobacter aerogenes-catalyzed microbial fuel cell (MFC) with a carbon-based anode that exhibited a maximum power density of 2.51 W/m3 in the absence of artificial electron mediators. The MFC was started up rapidly, within hours, and the current generation in the early stage was demonstrated to result from in situ oxidation of biohydrogen produced by E. aerogenes during glucose fermentation. Over periodic replacement of substrate, both planktonic biomass in the culture liquid and hydrogen productivity decreased, while increased power density and coulombic efficiency and decreased internal resistance were unexpectedly observed. Using scanning electron microscopy and cyclic voltammetry, it was found that the enhanced MFC performance was associated with the development of electroactive biofilm on the anodic surface, proposed to involve an acclimation and selection process of E. aerogenes cells under electrochemical tension. The significant advantage of rapid start-up and the ability to develop an electroactive biofilm identifies E. aerogenes as a suitable biocatalyst for MFC applications. 相似文献
7.
Comparison of anode bacterial communities and performance in microbial fuel cells with different electron donors 总被引:5,自引:0,他引:5
Microbial fuel cells (MFCs) harness the electrochemical activity of certain microbes for the production of electricity from reduced compounds. Characterizations of MFC anode biofilms have collectively shown very diverse microbial communities, raising ecological questions about competition and community succession within these anode-reducing communities. Three sets of triplicate, two-chamber MFCs inoculated with anaerobic sludge and differing in energy sources (acetate, lactate, and glucose) were operated to explore these questions. Based on 16S rDNA-targeted denaturing gradient gel electrophoresis (DGGE), all anode communities contained sequences closely affiliated with Geobacter sulfurreducens (>99% similarity) and an uncultured bacterium clone in the Bacteroidetes class (99% similarity). Various other Geobacter-like sequences were also enriched in most of the anode biofilms. While the anode communities in replicate reactors for each substrate generally converged to a reproducible community, there were some variations in the relative distribution of these putative anode-reducing Geobacter-like strains. Firmicutes were found only in glucose-fed MFCs, presumably serving the roles of converting complex carbon into simple molecules and scavenging oxygen. The maximum current density in these systems was negatively correlated with internal resistance variations among replicate reactors and, likely, was only minimally affected by anode community differences in these two-chamber MFCs with high internal resistance. 相似文献
8.
9.
Wei Guo Yanrui Cui Hong Song Jianhui Sun 《Bioprocess and biosystems engineering》2014,37(9):1749-1758
Development of highly efficient anode is critical for enhancing the power output of microbial fuel cells (MFCs). The aim of this work is to investigate whether modification of carbon paper (CP) anode with graphene (GR) via layer-by-layer assembly technique is an effective approach to promote the electricity generation and methyl orange removal in MFCs. Using cyclic voltammetry and electrochemical impedance spectroscopy, the GR/CP electrode exhibited better electrochemical behavior. Scanning electron microscopy results revealed that the surface roughness of GR/CP increased, which was favorable for more bacteria to attach to the anode surface. The MFCs equipped with GR/CP anode achieved a stable maximum power density of 368 mW m?2 under 1,000 Ω external resistance and a start time for the initial maximum voltage of 180 h, which were, respectively, 51 % higher and 31 % shorter than the corresponding values of the MFCs with blank anode. The anode and cathode polarization curves revealed negligible difference in cathode potentials but obviously difference in anode potentials, indicating that the GR-modified anode other than the cathode was responsible for the performance improvement of MFC. Meanwhile, compared with MFCs with blank anode, 11 % higher decolorization efficiency and 16 % higher the chemical oxygen demand removal rate were achieved in MFC with GR-modified anode during electricity generation. This study might provide an effective way to modify the anode for enhanced electricity generation and efficient removal of azo dye in MFCs. 相似文献
10.
The effect of the anions, phosphate and sulphate, on normal rates of excretion of potassium in dogs.
C Baylis W J O'Connor 《Quarterly journal of experimental physiology and cognate medical sciences》1976,61(4):341-350
Small doses of (NH4)2HPO4 or KH2PO4 by stomach tube caused increase in plasma PO4 and PO4 excretion. Above a threshold of 0-8 mmol. 1(-1), increase of plasma PO4 by 0-5 mmol. 1(-1) caused PO4 excretion to increase by about 35 mumol. min.-1 After KH2PO4 this relationship was not altered by the concurrent increases in plasma K and K excretion. After doses of (NH4)2SO4 or K2SO4, excretion of SO4 was similarly related to plasma SO4 and was independent of plasma K and K excretion. An effect of PO4 on K excretion was observed after doses of (NH4)2HPO4, when increased excretion of PO4 was accompanied by increased excretion of K without change in plasma K. There was also increased excretion of NH4 and a small increase in Na excretion. The changes were similar to those produced by (NH4)2SO4 [O'Connor and Summerill, 1976]. KH2PO4 and K2SO4 produced increase in plasma K and increased excretion of K not significantly different from the changes produced by KCl or KHCO3 [Baylis and O'Connor, 1976]. After KH2PO2 or K2SO4, the urinary anion was PO4 or SO4, instead of Cl and HCO3. Any effect of anions on K excretion was much less than the effect of increase in plasma K. At low rates of excretion of K, increased urinary excretion of impermeant anion can determine increased excretion of K. However, the effect of anion is small in comparison with the effect of increase in plasma K. 相似文献
11.
Yang-Chun Yong Zhi-Hong Liao Jian-Zhong Sun Tao Zheng Rong-Rong Jiang Hao Song 《Process Biochemistry》2013,48(12):1947-1951
Coulombic efficiency and stability of electricity output are crucial for practical applications of microbial fuel cells (MFCs). In this study, a cell immobilization method for electrogenic microorganism in MFCs using graphite/alginate granules is developed. The MFC with immobilized cell granules delivered a much more stable electricity output than that with suspension cells, and resulted in a ~0.8 to 1.7 times improvement on coulombic efficiency compared to the suspension mode. Impressively, with the conductive graphite/alginate/cells granules, the internal resistance of the MFC decreased dramatically. Moreover, the cell immobilized MFC showed a much higher tolerance to the shock of high salt concentration than the MFC with suspension cells. The results substantiated that immobilization of electrogenic microorganism for MFCs could be achieved by the method developed here, and it is promising for practical application in energy harvesting from wastewater by MFCs. 相似文献
12.
Rod-shaped Alphaproteobacteria possessing long prosthecae-like appendages have been detected abundantly in biofilms attaching onto anode graphite of cellulose-fed microbial fuel cells (MFCs). To identify their ecological roles, the present study isolated a corresponding bacterium (strain Mfc52) by direct plating of a biofilm suspension onto a solid medium containing glucose and ferric ion. Phylogenetic analysis revealed that this strain is deeply branched in the class Alphaproteobacteria and may represent a novel order. Strain Mfc52 fermented sugars and produced lactate, acetate, and fumarate, whereas ferric ion stimulated the growth on glucose. When an MFC was inoculated with this strain and supplemented with glucose, it fermented glucose and generated electricity by oxidizing organic acids produced from glucose. Electron micrographs showed that a fraction of cells in a liquid culture had prosthecae-like appendages that were abundantly observed in anode biofilm. These observations suggest that the bacterial population represented by strain Mfc52 shared an important niche in the cellulose-fed MFC, where it generated electricity by oxidizing intermediate metabolites from cellulose degradation. 相似文献
13.
目的:提高酵母产γ-氨基丁酸的能力。方法:采用单因素及正交设计实验对酵母产γ-氨基丁酸(GABA)的培养基进行优化。结果:确定最适碳源为葡萄糖,最佳氮源为蛋白胨和硫酸铵复合氮源,合适的无机盐为KH2PO4;最佳发酵培养基为3%葡萄糖,3%蛋白胨,0.3%(NH4)2SO4和0.1%KH2PO4。在此培养条件下,摇瓶发酵可以获得1.690g.L-1的GABA产量。结论:发酵培养基的优化,提高了菌株产γ-氨基丁酸的能力。 相似文献
14.
Flexible and Stretchable Biobatteries: Monolithic Integration of Membrane‐Free Microbial Fuel Cells in a Single Textile Layer 下载免费PDF全文
The fabrication and performance of a flexible and stretchable microbial fuel cell (MFC) monolithically integrated into a single sheet of textile substrate are reported. The single‐layer textile MFC uses Pseudomonas aeruginosa (PAO1) as a biocatalyst to produce a maximum power of 6.4 µW cm?2 and current density of 52 µA cm?2, which are substantially higher than previous textile‐MFCs and are similar to other flexible paper‐based MFCs. The textile MFC demonstrates a stable performance with repeated stretching and twisting cycles. The membrane‐less single‐chamber configuration drastically simplifies the fabrication and improves the performance of the MFC. A conductive and hydrophilic anode in a 3D fabric microchamber maximizes bacterial electricity generation from a liquid environment and a silver oxide/silver solid‐state cathode reduces cathodic overpotential for fast catalytic reaction. A simple batch fabrication approach simultaneously constructs 35 individual devices, which will revolutionize the mass production of textile MFCs. This stretchable and twistable power device printed directly onto a single textile substrate can establish a standardized platform for textile‐based biobatteries and will be potentially integrated into wearable electronics in the future. 相似文献
15.
Currently, acrylic acid is produced at a low yield by the resting cells of Clostridium propionicum with the supplement of extra electron acceptors. As an alternative way, acrylic acid production coupled with electricity generation was achieved by C. propionicum‐based microbial fuel cells (MFCs). Electricity was generated in the salt‐bridge MFCs with cysteine and resazurin in the anode chamber as mediators, and K3Fe(CN)6 as the cathode electron acceptor. Power generation was 21.78 mW/m2 with an internal resistance of 9809 Ω. Cyclic voltammograms indicated the main mechanism of power production was the electron transfer facilitated by mediators in the system. In the salt‐bridge MFC system, 0.694 mM acrylic acid was produced together with electricity generation. 相似文献
16.
Shao-Xiang Teng Zhong-Hua Tong Wen-Wei Li Shu-Guang Wang Guo-Ping Sheng Xian-Yang Shi Xian-Wei Liu Han-Qing Yu 《Applied microbiology and biotechnology》2010,87(6):2365-2372
Fermentative hydrogen production, as a process for clean energy recovery from organic wastewater, is limited by its low hydrogen
yield due to incomplete conversion of substrates, with most of the fermentation products being volatile fatty acids (VFAs).
Thus, further recovery of the energy from VFAs is expected. In this work, microbial fuel cell (MFC) was applied to recover
energy in the form of electricity from mixed VFAs of acetate, propionate, and butyrate. Response surface methodology was adopted
to investigate the relative contribution and possible interactions of the three components of VFAs. A stable electricity generation
was demonstrated in MFCs after the enrichment of electrochemically active bacteria. Analysis showed that power density was
more sensitive to the composition of mixed VFAs than coulombic efficiency. The electricity generation could mainly be attributed
to the portion of acetate and propionate. However, the two components showed an antagonistic effect when propionate exceeded
19%, causing a decrease in coulombic efficiency. Butyrate was found to exert a negative impact on both power density and coulombic
efficiency. Denaturing gradient gel electrophoresis profiles revealed the enrichment of electrochemically active bacteria
from the inoculum sludge. Proteobacteria (Beta-, Delta-) and Bacteroidetes were predominant in all VFA-fed MFCs. Shifts in
bacterial community structures were observed when different compositions of VFA mixtures were used as the electron donor.
The overall electron recovery efficiency may be increased from 15.7% to 27.4% if fermentative hydrogen production and MFC
processes are integrated. 相似文献
17.
The purpose of this study was to determine the effect of enrichment procedure on the performance and microbial diversity of
an air-cathode microbial fuel cell (MFC) which was explored for simultaneous azo dye decolorization and electricity generation.
Two different enrichment procedures in which glucose and Congo red were added into the MFCs sequentially (EP1) or simultaneously
(EP2) were tested by operating parallel MFCs independently for more than 6 months. The power density, electrode potential,
Congo red decolorization, biofilm morphology, and bacterial diversity of the MFCs under the two enrichment procedures were
compared and investigated. The results showed that the enrichment procedures have a negligible effect on the dye decolorization,
but significantly affected the electricity generation. More than 90% decolorization at dye concentration of 300 mg/L was achieved
within 170 h for the two tested enrichment procedures. However, the MFC with EP2 achieved a maximum power density of 192 mW/m2, which was 75% higher than that of the MFC with EP1 (110 mW/m2). The depressed surfaces of the bacteria in the MFC with EP1 indicated the allergic response caused by the subsequent addition
of Congo red. 16S rRNA sequencing analysis demonstrated a phylogenetic diversity in the communities of the anode biofilm and
showed clear differences between the anode-attached populations in the MFCs with a different enrichment procedure. This study
suggests that the enrichment procedure is important for the MFC explored for simultaneous dye decolorization and electricity
generation. 相似文献
18.
Increased sustainable electricity generation in up-flow air-cathode microbial fuel cells 总被引:1,自引:0,他引:1
Sustainable electricity was generated from glucose in up-flow air-cathode microbial fuel cells (MFCs) with carbon cloth cathode and carbon granular anode. Plastic sieves rather than membrane were used to separate the anode and cathode. Based on 1g/l glucose as substrate, a maximum volumetric power density of 25+/-4 W/m(3) (89 A/m(3)) was obtained for the MFC with a sieve area of 30 cm(2) and 49+/-3 W/m(3) (215 A/m(3)) for the MFC with a sieve area of 60 cm(2). The increased power density with larger sieve area was mainly due to the decrease of internal resistance according to the electrochemistry impedance spectroscopy analysis. Increasing the sieve area from 30 cm(2) to 60 cm(2) resulted in a decrease of overall internal resistance from 41 ohm to 27.5 ohm and a decrease of ohmic resistance from 24.3 ohm to 14 ohm. While increasing operational recirculation ratio (RR) decreased internal resistance and increased power output at low substrate concentration, the effect of RR on cell performance was negligible at higher substrate concentration. 相似文献
19.
Hamid Rismani-Yazdi Ann D. Christy Sarah M. CarverZhongtang Yu Burk A. DehorityOlli H. Tuovinen 《Bioresource technology》2011,102(1):278-283
External resistance affects the performance of microbial fuel cells (MFCs) by controlling the flow of electrons from the anode to the cathode. The purpose of this study was to determine the effect of external resistance on bacterial diversity and metabolism in MFCs. Four external resistances (20, 249, 480, and 1000 Ω) were tested by operating parallel MFCs independently at constant circuit loads for 10 weeks. A maximum power density of 66 mW m−2 was achieved by the 20 Ω MFCs, while the MFCs with 249, 480, and 1000 Ω external resistances produced 57.5, 27, and 47 mW m−2, respectively. Denaturing gradient gel electrophoresis analysis of partial 16S rRNA genes showed clear differences between the planktonic and anode-attached populations at various external resistances. Concentrations of short chain fatty acids were higher in MFCs with larger circuit loads, suggesting that fermentative metabolism dominated over anaerobic respiration using the anode as the final electron acceptor. 相似文献
20.
An iTRAQ characterisation of the role of TolC during electron transfer from Shewanella oneidensis MR‐1 下载免费PDF全文
Stephen Jaffe Grzegorz Pasternak Trong Khoa Pham Pablo Ledezma Simon T. E. Hall Ioannis A. Ieropoulos Phillip C. Wright 《Proteomics》2016,16(21):2764-2775
Anodophilic bacteria have the ability to generate electricity in microbial fuel cells (MFCs) by extracellular electron transfer to the anode. We investigated the anode‐specific responses of Shewanella oneidensis MR‐1, an exoelectroactive Gammaproteobacterium, using for the first time iTRAQ and 2D‐LC MS/MS driven membrane proteomics to compare protein abundances in S. oneidensis when generating power in MFCs, and growing in a continuous culture. The regulated dataset produced was enriched in membrane proteins. Proteins shown to be more abundant in anaerobic electroactive anodic cells included efflux pump TolC and an uncharacterised tetratricopeptide repeat (TPR) protein, whilst the TonB2 system and associated uncharacterised proteins such as TtpC2 and DUF3450 were more abundant in microaerobic planktonic cells. In order to validate the iTRAQ data, the functional role for TolC was examined using a δTolC knockout mutant of S. oneidensis. Possible roles for the uncharacterised proteins were identified using comparative bioinformatics. We demonstrate that employing an insoluble extracellular electron acceptor requires multiple proteins involved in cell surface properties. All MS and processed data are available via ProteomeXchange with identifier PXD004090. 相似文献