251
|
Nimje VR, Chen CY, Chen HR, Chen CC, Huang YM, Tseng MJ, Cheng KC, Chang YF. Comparative bioelectricity production from various wastewaters in microbial fuel cells using mixed cultures and a pure strain of Shewanella oneidensis. BIORESOURCE TECHNOLOGY 2012; 104:315-323. [PMID: 22123299 DOI: 10.1016/j.biortech.2011.09.129] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2011] [Revised: 09/27/2011] [Accepted: 09/29/2011] [Indexed: 05/31/2023]
Abstract
Current and power density from four wastewaters, agriculture (AWW), domestic (DWW), paper (PWW), and food/dairy (FDWW), were comparatively evaluated in combination with three inocula: wastewater endogenous microbes (MFC1), Shewanella oneidensis MR-1 (MFC2), and wastewater endogenous microbes with MR-1 (MFC3) in single chamber microbial fuel cells (MFC). Using AWW (0.011 mA/cm(2); 0.0013 mW/cm(2)) and DWW (0.017 mA/cm(2); 0.0036 mW/cm(2)), MFC2 was the best candidate providing the maximum current, whereas AWW-MFC1 and DWW-MFC1 were unable to construct a well-established MFC. FDWW produced a maximum current from MFC3 (0.037 mA/cm(2); 0.015 mW/cm(2)), and confirmed the unsuitability of MFC2 at an alkaline pH. FDWW-MFC3 also performed best with the highest substrate degradation and coulombic efficiency. Mixed culture in MFC3 resulted in higher current generation under the influence of MR-1 (except in PWW), indicating the endogenous microbes were not solely responsible for the current but the outperformance was significantly attributed to the association of MR-1.
Collapse
Affiliation(s)
- Vanita Roshan Nimje
- Department of Life Science, National Chung Cheng University, 168 University Road, Minhsiung, Chiayi 621, Taiwan
| | | | | | | | | | | | | | | |
Collapse
|
252
|
Jeremiasse AW, Hamelers HV, Croese E, Buisman CJ. Acetate enhances startup of a H2-producing microbial biocathode. Biotechnol Bioeng 2011; 109:657-64. [DOI: 10.1002/bit.24338] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 09/25/2011] [Accepted: 10/06/2011] [Indexed: 11/11/2022]
|
253
|
Sun D, Call DF, Kiely PD, Wang A, Logan BE. Syntrophic interactions improve power production in formic acid fed MFCs operated with set anode potentials or fixed resistances. Biotechnol Bioeng 2011; 109:405-14. [DOI: 10.1002/bit.23348] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2011] [Revised: 09/29/2011] [Accepted: 09/30/2011] [Indexed: 11/09/2022]
|
254
|
The Performance of a Microbial Fuel Cell Depends Strongly on Anode Geometry: A Multidimensional Modeling Study. Bull Math Biol 2011; 74:834-57. [DOI: 10.1007/s11538-011-9690-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Accepted: 08/05/2011] [Indexed: 10/16/2022]
|
255
|
Patil SA, Harnisch F, Koch C, Hübschmann T, Fetzer I, Carmona-Martínez AA, Müller S, Schröder U. Electroactive mixed culture derived biofilms in microbial bioelectrochemical systems: the role of pH on biofilm formation, performance and composition. BIORESOURCE TECHNOLOGY 2011; 102:9683-9690. [PMID: 21855323 DOI: 10.1016/j.biortech.2011.07.087] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Revised: 07/21/2011] [Accepted: 07/22/2011] [Indexed: 05/31/2023]
Abstract
The pH-value played a crucial role for the development and current production of anodic microbial electroactive biofilms. It was demonstrated that only a narrow pH-window, ranging from pH 6 to 9, was suitable for growth and operation of biofilms derived from pH-neutral wastewater. Any stronger deviation from pH neutral conditions led to a substantial decrease in the biofilm performance. Thus, average current densities of 151, 821 and 730 μA cm(-2) were measured for anode biofilms grown and operated at pH 6, 7 and 9 respectively. The microbial diversity of the anode chamber community during the biofilm selection process was studied using the low cost method flow-cytometry. Thereby, it was demonstrated that the pH value as well as the microbial inocula had an impact on the resulting anode community structure. As shown by cyclic voltammetry the electron transfer thermodynamics of the biofilms was strongly depending on the solution's pH-value.
Collapse
Affiliation(s)
- Sunil A Patil
- Institute of Environmental and Sustainable Chemistry, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
| | | | | | | | | | | | | | | |
Collapse
|
256
|
Liu G, Yates MD, Cheng S, Call DF, Sun D, Logan BE. Examination of microbial fuel cell start-up times with domestic wastewater and additional amendments. BIORESOURCE TECHNOLOGY 2011; 102:7301-7306. [PMID: 21601444 DOI: 10.1016/j.biortech.2011.04.087] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2011] [Revised: 04/21/2011] [Accepted: 04/27/2011] [Indexed: 05/27/2023]
Abstract
Rapid startup of microbial fuel cells (MFCs) and other bioreactors is desirable when treating wastewaters. The startup time with unamended wastewater (118 h) was similar to that obtained by adding acetate or fumarate (110-115 h), and less than that with glucose (181 h) or Fe(III) (353 h). Initial current production took longer when phosphate buffer was added, with startup times increasing with concentration from 149 h (25 mM) to 251 h (50 mM) and 526 h (100 mM). Microbial communities that developed in the reactors contained Betaproteobacteria, Acetoanaerobium noterae, and Chlorobium sp. Anode biomass densities ranged from 200 to 600 μg/cm(2) for all amendments except Fe(Ш) (1650 μg/cm(2)). Wastewater produced 91 mW/m(2), with the other MFCs producing 50 mW/m(2) (fumarate) to 103mW/m(2) (Fe(III)) when amendments were removed. These experiments show that wastewater alone is sufficient to acclimate the reactor without the need for additional chemical amendments.
Collapse
Affiliation(s)
- Guangli Liu
- School of Environmental Science & Engineering, Sun Yat-sen University, Guangzhou, PR China
| | | | | | | | | | | |
Collapse
|
257
|
Ziv-El M, Delgado AG, Yao Y, Kang DW, Nelson KG, Halden RU, Krajmalnik-Brown R. Development and characterization of DehaloR^2, a novel anaerobic microbial consortium performing rapid dechlorination of TCE to ethene. Appl Microbiol Biotechnol 2011; 92:1063-71. [PMID: 21667274 DOI: 10.1007/s00253-011-3388-y] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Revised: 05/12/2011] [Accepted: 05/14/2011] [Indexed: 01/05/2023]
Abstract
A novel anaerobic consortium, named DehaloR^2, that performs rapid and complete reductive dechlorination of trichloroethene (TCE) to ethene is described. DehaloR^2 was developed from estuarine sediment from the Back River of the Chesapeake Bay and has been stably maintained in the laboratory for over 2 years. Initial sediment microcosms showed incomplete reduction of TCE to DCE with a ratio of trans- to cis- isomers of 1.67. However, complete reduction to ethene was achieved within 10 days after transfer of the consortium to sediment-free media and was accompanied by a shift to cis-DCE as the prevailing intermediate metabolite. The microbial community shifted from dominance of the Proteobacterial phylum in the sediment to Firmicutes and Chloroflexi in DehaloR^2, containing the genera Acetobacterium, Clostridium, and the dechlorinators Dehalococcoides. Also present were Spirochaetes, possible acetogens, and Geobacter which encompass previously described dechlorinators. Rates of TCE to ethene reductive dechlorination reached 2.83 mM Cl- d(-1) in batch bottles with a Dehalococcoides sp. density of 1.54E+11 gene copies per liter, comparing favorably to other enrichment cultures described in the literature and identifying DehaloR^2 as a promising consortium for use in bioremediation of chlorinated ethene-impacted environments.
Collapse
Affiliation(s)
- Michal Ziv-El
- Swette Center for Environmental Biotechnology, Biodesign Institute at Arizona State University, PO Box 875001, Tempe, AZ 85287-5001, USA
| | | | | | | | | | | | | |
Collapse
|
258
|
Gong Y, Radachowsky SE, Wolf M, Nielsen ME, Girguis PR, Reimers CE. Benthic microbial fuel cell as direct power source for an acoustic modem and seawater oxygen/temperature sensor system. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:5047-5053. [PMID: 21545151 DOI: 10.1021/es104383q] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Supported by the natural potential difference between anoxic sediment and oxic seawater, benthic microbial fuel cells (BMFCs) promise to be ideal power sources for certain low-power marine sensors and communication devices. In this study a chambered BMFC with a 0.25 m(2) footprint was used to power an acoustic modem interfaced with an oceanographic sensor that measures dissolved oxygen and temperature. The experiment was conducted in Yaquina Bay, Oregon over 50 days. Several improvements were made in the BMFC design and power management system based on lessons learned from earlier prototypes. The energy was harvested by a dynamic gain charge pump circuit that maintains a desired point on the BMFC's power curve and stores the energy in a 200 F supercapacitor. The system also used an ultralow power microcontroller and quartz clock to read the oxygen/temperature sensor hourly, store data with a time stamp, and perform daily polarizations. Data records were transmitted to the surface by the acoustic modem every 1-5 days after receiving an acoustic prompt from a surface hydrophone. After jump-starting energy production with supplemental macroalgae placed in the BMFC's anode chamber, the average power density of the BMFC adjusted to 44 mW/m(2) of seafloor area which is better than past demonstrations at this site. The highest power density was 158 mW/m(2), and the useful energy produced and stored was ≥ 1.7 times the energy required to operate the system.
Collapse
Affiliation(s)
- Yanming Gong
- College of Oceanic & Atmospheric Sciences, Hatfield Marine Science Center, Oregon State University, Newport, Oregon 97365, USA
| | | | | | | | | | | |
Collapse
|
259
|
Cercado-Quezada B, Delia ML, Bergel A. Electrochemical micro-structuring of graphite felt electrodes for accelerated formation of electroactive biofilms on microbial anodes. Electrochem commun 2011. [DOI: 10.1016/j.elecom.2011.02.015] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|
260
|
Borole AP, Hamilton CY, Vishnivetskaya TA. Enhancement in current density and energy conversion efficiency of 3-dimensional MFC anodes using pre-enriched consortium and continuous supply of electron donors. BIORESOURCE TECHNOLOGY 2011; 102:5098-5104. [PMID: 21334884 DOI: 10.1016/j.biortech.2011.01.045] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 01/11/2011] [Accepted: 01/15/2011] [Indexed: 05/30/2023]
Abstract
Using a pre-enriched microbial consortium as the inoculum and continuous supply of carbon source, improvement in performance of a three-dimensional, flow-through MFC anode utilizing ferricyanide cathode was investigated. The power density increased from 170 W/m(3) (1800 mW/m(2)) to 580 W/m(3) (6130 mW/m(2)), when the carbon loading increased from 2.5 g/l-day to 50 g/l-day. The coulombic efficiency (CE) decreased from 90% to 23% with increasing carbon loading. The CEs are among the highest reported for glucose and lactate as the substrate with the maximum current density reaching 15.1A/m(2). This suggests establishment of a very high performance exoelectrogenic microbial consortium at the anode. A maximum energy conversion efficiency of 54% was observed at a loading of 2.5 g/l-day. Biological characterization of the consortium showed presence of Burkholderiales and Rhodocyclales as the dominant members. Imaging of the biofilms revealed thinner biofilms compared to the inoculum MFC, but a 1.9-fold higher power density.
Collapse
Affiliation(s)
- Abhijeet P Borole
- BioSciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6226, USA
| | | | | |
Collapse
|
261
|
Choi S, Lee HS, Yang Y, Parameswaran P, Torres CI, Rittmann BE, Chae J. A μL-scale micromachined microbial fuel cell having high power density. LAB ON A CHIP 2011; 11:1110-1117. [PMID: 21311808 DOI: 10.1039/c0lc00494d] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We report a MEMS (Micro-Electro-Mechanical Systems)-based microbial fuel cell (MFC) that produces a high power density. The MFC features 4.5-μL anode/cathode chambers defined by 20-μm-thick photo-definable polydimethylsiloxane (PDMS) films. The MFC uses a Geobacter-enriched mixed bacterial culture, anode-respiring bacteria (ARB) that produces a conductive biofilm matrix. The MEMS MFC generated a maximum current density of 16,000 μA cm(-3) (33 μA cm(-2)) and power density of 2300 μW cm(-3) (4.7 μW cm(-2)), both of which are substantially greater than achieved by previous MEMS MFCs. The coulombic efficiency of the MEMS MFC was at least 31%, by far the highest value among reported MEMS MFCs. The performance improvements came from using highly efficient ARB, minimizing the impact of oxygen intrusion to the anode chamber, having a large specific surface area that led to low internal resistance.
Collapse
Affiliation(s)
- Seokheun Choi
- School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona, USA.
| | | | | | | | | | | | | |
Collapse
|
262
|
Ren Z, Yan H, Wang W, Mench MM, Regan JM. Characterization of microbial fuel cells at microbially and electrochemically meaningful time scales. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:2435-2441. [PMID: 21329346 DOI: 10.1021/es103115a] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The variable biocatalyst density in a microbial fuel cell (MFC) anode biofilm is a unique feature of MFCs relative to other electrochemical systems, yet performance characterizations of MFCs typically involve analyses at electrochemically relevant time scales that are insufficient to account for these variable biocatalyst effects. This study investigated the electrochemical performance and the development of anode biofilm architecture under different external loadings, with duplicate acetate-fed single-chamber MFCs stabilized at each resistance for microbially relevant time scales. Power density curves from these steady-state reactors generally showed comparable profiles despite the fact that anode biofilm architectures and communities varied considerably, showing that steady-state biofilm differences had little influence on electrochemical performance until the steady-state external loading was much larger than the reactor internal resistance. Filamentous bacteria were dominant on the anodes under high external resistances (1000 and 5000 Ω), while more diverse rod-shaped cells formed dense biofilms under lower resistances (10, 50, and 265 Ω). Anode charge transfer resistance decreased with decreasing fixed external resistances, but was consistently 2 orders of magnitude higher than the resistance at the cathode. Cell counting showed an inverse exponential correlation between cell numbers and external resistances. This direct link of MFC anode biofilm evolution with external resistance and electricity production offers several operational strategies for system optimization.
Collapse
Affiliation(s)
- Zhiyong Ren
- Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States.
| | | | | | | | | |
Collapse
|
263
|
Millo D, Harnisch F, Patil SA, Ly HK, Schröder U, Hildebrandt P. Spektroelektrochemische In-situ-Untersuchung von elektrokatalytischen mikrobiellen Biofilmen mit oberflächenverstärkter Resonanz-Raman-Spektroskopie. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201006046] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
264
|
Millo D, Harnisch F, Patil SA, Ly HK, Schröder U, Hildebrandt P. In situ spectroelectrochemical investigation of electrocatalytic microbial biofilms by surface-enhanced resonance Raman spectroscopy. Angew Chem Int Ed Engl 2011; 50:2625-7. [PMID: 21370352 DOI: 10.1002/anie.201006046] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Revised: 11/29/2010] [Indexed: 11/10/2022]
Affiliation(s)
- Diego Millo
- Institut für Chemie, Sekr. PC14, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany.
| | | | | | | | | | | |
Collapse
|
265
|
Pinto RP, Srinivasan B, Guiot SR, Tartakovsky B. The effect of real-time external resistance optimization on microbial fuel cell performance. WATER RESEARCH 2011; 45:1571-8. [PMID: 21167550 DOI: 10.1016/j.watres.2010.11.033] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Revised: 11/21/2010] [Accepted: 11/22/2010] [Indexed: 05/15/2023]
Abstract
This work evaluates the impact of the external resistance (electrical load) on the long-term performance of a microbial fuel cell (MFC) and demonstrates the real-time optimization of the external resistance. For this purpose, acetate-fed MFCs were operated at external resistances, which were above, below, or equal to the internal resistance of a corresponding MFC. A perturbation/observation algorithm was used for the real-time optimal selection of the external resistance. MFC operation at the optimal external resistance resulted in increased power output, improved Coulombic efficiency, and low methane production. Furthermore, the efficiency of the perturbation/observation algorithm for maximizing long-term MFC performance was confirmed by operating an MFC fed with synthetic wastewater for over 40 days. In this test an average Coulombic efficiency of 29% was achieved.
Collapse
Affiliation(s)
- R P Pinto
- Biotechnology Research Institute, National Research Council, 6100 Royalmount Ave., Montréal, Que., Canada
| | | | | | | |
Collapse
|
266
|
Gene expression and deletion analysis of mechanisms for electron transfer from electrodes to Geobacter sulfurreducens. Bioelectrochemistry 2011; 80:142-50. [DOI: 10.1016/j.bioelechem.2010.07.005] [Citation(s) in RCA: 162] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Revised: 07/06/2010] [Accepted: 07/15/2010] [Indexed: 11/23/2022]
|
267
|
Lovley DR, Ueki T, Zhang T, Malvankar NS, Shrestha PM, Flanagan KA, Aklujkar M, Butler JE, Giloteaux L, Rotaru AE, Holmes DE, Franks AE, Orellana R, Risso C, Nevin KP. Geobacter: the microbe electric's physiology, ecology, and practical applications. Adv Microb Physiol 2011; 59:1-100. [PMID: 22114840 DOI: 10.1016/b978-0-12-387661-4.00004-5] [Citation(s) in RCA: 384] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Geobacter species specialize in making electrical contacts with extracellular electron acceptors and other organisms. This permits Geobacter species to fill important niches in a diversity of anaerobic environments. Geobacter species appear to be the primary agents for coupling the oxidation of organic compounds to the reduction of insoluble Fe(III) and Mn(IV) oxides in many soils and sediments, a process of global biogeochemical significance. Some Geobacter species can anaerobically oxidize aromatic hydrocarbons and play an important role in aromatic hydrocarbon removal from contaminated aquifers. The ability of Geobacter species to reductively precipitate uranium and related contaminants has led to the development of bioremediation strategies for contaminated environments. Geobacter species produce higher current densities than any other known organism in microbial fuel cells and are common colonizers of electrodes harvesting electricity from organic wastes and aquatic sediments. Direct interspecies electron exchange between Geobacter species and syntrophic partners appears to be an important process in anaerobic wastewater digesters. Functional and comparative genomic studies have begun to reveal important aspects of Geobacter physiology and regulation, but much remains unexplored. Quantifying key gene transcripts and proteins of subsurface Geobacter communities has proven to be a powerful approach to diagnose the in situ physiological status of Geobacter species during groundwater bioremediation. The growth and activity of Geobacter species in the subsurface and their biogeochemical impact under different environmental conditions can be predicted with a systems biology approach in which genome-scale metabolic models are coupled with appropriate physical/chemical models. The proficiency of Geobacter species in transferring electrons to insoluble minerals, electrodes, and possibly other microorganisms can be attributed to their unique "microbial nanowires," pili that conduct electrons along their length with metallic-like conductivity. Surprisingly, the abundant c-type cytochromes of Geobacter species do not contribute to this long-range electron transport, but cytochromes are important for making the terminal electrical connections with Fe(III) oxides and electrodes and also function as capacitors, storing charge to permit continued respiration when extracellular electron acceptors are temporarily unavailable. The high conductivity of Geobacter pili and biofilms and the ability of biofilms to function as supercapacitors are novel properties that might contribute to the field of bioelectronics. The study of Geobacter species has revealed a remarkable number of microbial physiological properties that had not previously been described in any microorganism. Further investigation of these environmentally relevant and physiologically unique organisms is warranted.
Collapse
Affiliation(s)
- Derek R Lovley
- Department of Microbiology and Environmental Biotechnology Center, University of Massachusetts, Amherst, Massachusetts, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
268
|
Rosenbaum M, Aulenta F, Villano M, Angenent LT. Cathodes as electron donors for microbial metabolism: which extracellular electron transfer mechanisms are involved? BIORESOURCE TECHNOLOGY 2011; 102:324-33. [PMID: 20688515 DOI: 10.1016/j.biortech.2010.07.008] [Citation(s) in RCA: 283] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Revised: 06/29/2010] [Accepted: 07/02/2010] [Indexed: 05/20/2023]
Abstract
This review illuminates extracellular electron transfer mechanisms that may be involved in microbial bioelectrochemical systems with biocathodes. Microbially-catalyzed cathodes are evolving for new bioprocessing applications for waste(water) treatment, carbon dioxide fixation, chemical product formation, or bioremediation. Extracellular electron transfer processes in biological anodes, were the electrode serves as electron acceptor, have been widely studied. However, for biological cathodes the question remains: what are the biochemical mechanisms for the extracellular electron transfer from a cathode (electron donor) to a microorganism? This question was approached by not only analysing the literature on biocathodes, but also by investigating known extracellular microbial oxidation reactions in environmental processes. Here, it is predicted that in direct electron transfer reactions, c-type cytochromes often together with hydrogenases play a critical role and that, in mediated electron transfer reactions, natural redox mediators, such as PQQ, will be involved in the bioelectrochemical reaction. These mechanisms are very similar to processes at the bioanode, but the components operate at different redox potentials. The biocatalyzed cathode reactions, thereby, are not necessarily energy conserving for the microorganism.
Collapse
Affiliation(s)
- Miriam Rosenbaum
- Department of Biological and Environmental Engineering, Cornell University, 214 Riley-Robb Hall, Ithaca, NY 14853, USA.
| | | | | | | |
Collapse
|
269
|
Parameswaran P, Torres CI, Lee HS, Rittmann BE, Krajmalnik-Brown R. Hydrogen consumption in microbial electrochemical systems (MXCs): the role of homo-acetogenic bacteria. BIORESOURCE TECHNOLOGY 2011; 102:263-271. [PMID: 20430615 DOI: 10.1016/j.biortech.2010.03.133] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Revised: 03/23/2010] [Accepted: 03/29/2010] [Indexed: 05/29/2023]
Abstract
Homo-acetogens in the anode of a microbial electrolysis cell (MEC) fed with H(2) as sole electron donor allowed current densities similar to acetate-fed biofilm anodes (∼10 A/m(2)). Evidence for homo-acetogens included accumulation of acetate at high concentrations (up to 18 mM) in the anode compartment; detection of formate, a known intermediate during reductive acetogenesis by the acetyl-CoA pathway; and detection of formyl tetrahydrofolate synthetase (FTHFS) genes by quantitative real-time PCR. Current production and acetate accumulation increased in parallel in batch and continuous mode, while both values decreased simultaneously at short hydraulic retention times (1h) in the anode compartment, which limited suspended homo-acetogens. Acetate produced by homo-acetogens accounted for about 88% of the current density of 10A/m(2), but the current density was sustained at 4A/m(2) at short hydraulic retention time because of a robust partnership of homo-acetogens and anode respiring bacteria (ARB) in the biofilm anode.
Collapse
Affiliation(s)
- Prathap Parameswaran
- Center for Environmental Biotechnology, The Biodesign Institute at Arizona State University, PO Box 875701, Tempe, AZ 85287-5701, USA.
| | | | | | | | | |
Collapse
|
270
|
Marcus AK, Torres CI, Rittmann BE. Analysis of a microbial electrochemical cell using the proton condition in biofilm (PCBIOFILM) model. BIORESOURCE TECHNOLOGY 2011; 102:253-262. [PMID: 20395137 DOI: 10.1016/j.biortech.2010.03.100] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Revised: 03/18/2010] [Accepted: 03/20/2010] [Indexed: 05/29/2023]
Abstract
Common to all microbial electrochemical cells (MXCs) are the anode-respiring bacteria (ARB), which transfer electrons to an anode and release protons that must transport out of the biofilm. Here, we develop a novel modeling platform, Proton Condition in BIOFILM (PCBIOFILM), with a structure geared towards mechanistically explaining: (1) how the ARB half reaction produces enough acid to inhibit the ARB by low pH; (2) how the diffusion of alkalinity carriers (phosphates and carbonates) control the pH gradients in the biofilm anode; (3) how increasing alkalinity attenuates pH gradients and increases current; and (4) why carbonates enable higher current density than phosphates. Analysis of literature data using PCBIOFILM supports the hypothesis that alkalinity limits the maximum current density for MXCs. An alkalinity criterion for eliminating low-pH limitation - 12 mgCaCO(3)/mg BOD--implies that a practical MXC can achieve a maximum current density with an effluent quality comparable to anaerobic digestion.
Collapse
Affiliation(s)
- Andrew K Marcus
- Center for Environmental Biotechnology, The Biodesign Institute at Arizona State University, PO Box 875701, Tempe, AZ 85287-5701, USA.
| | | | | |
Collapse
|
271
|
Rismani-Yazdi H, Christy AD, Carver SM, Yu Z, Dehority BA, Tuovinen OH. Effect of external resistance on bacterial diversity and metabolism in cellulose-fed microbial fuel cells. BIORESOURCE TECHNOLOGY 2011; 102:278-283. [PMID: 20627719 DOI: 10.1016/j.biortech.2010.05.012] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2010] [Revised: 05/01/2010] [Accepted: 05/04/2010] [Indexed: 05/29/2023]
Abstract
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.
Collapse
Affiliation(s)
- Hamid Rismani-Yazdi
- Department of Food, Agricultural and Biological Engineering, Ohio State University, 590 Woody Hayes Drive, Columbus, OH 43210, USA
| | | | | | | | | | | |
Collapse
|
272
|
Kiely PD, Cusick R, Call DF, Selembo PA, Regan JM, Logan BE. Anode microbial communities produced by changing from microbial fuel cell to microbial electrolysis cell operation using two different wastewaters. BIORESOURCE TECHNOLOGY 2011; 102:388-394. [PMID: 20554197 DOI: 10.1016/j.biortech.2010.05.019] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2010] [Revised: 05/04/2010] [Accepted: 05/06/2010] [Indexed: 05/29/2023]
Abstract
Conditions in microbial fuel cells (MFCs) differ from those in microbial electrolysis cells (MECs) due to the intrusion of oxygen through the cathode and the release of H(2) gas into solution. Based on 16S rRNA gene clone libraries, anode communities in reactors fed acetic acid decreased in species richness and diversity, and increased in numbers of Geobacter sulfurreducens, when reactors were shifted from MFCs to MECs. With a complex source of organic matter (potato wastewater), the proportion of Geobacteraceae remained constant when MFCs were converted into MECs, but the percentage of clones belonging to G. sulfurreducens decreased and the percentage of G. metallireducens clones increased. A dairy manure wastewater-fed MFC produced little power, and had more diverse microbial communities, but did not generate current in an MEC. These results show changes in Geobacter species in response to the MEC environment and that higher species diversity is not correlated with current.
Collapse
Affiliation(s)
- Patrick D Kiely
- Department of Civil and Environmental Engineering, H(2)E Center, 131 Sackett Building, The Pennsylvannia State University, University Park, PA 16802, USA
| | | | | | | | | | | |
Collapse
|
273
|
Influence of external resistance on electrogenesis, methanogenesis, and anode prokaryotic communities in microbial fuel cells. Appl Environ Microbiol 2010; 77:564-71. [PMID: 21075886 DOI: 10.1128/aem.01392-10] [Citation(s) in RCA: 176] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The external resistance (R(ext)) of microbial fuel cells (MFCs) regulates both the anode availability as an electron acceptor and the electron flux through the circuit. We evaluated the effects of R(ext) on MFCs using acetate or glucose. The average current densities (I) ranged from 40.5 mA/m(2) (9,800 Ω) to 284.5 mA/m(2) (150 Ω) for acetate-fed MFCs (acetate-fed reactors [ARs]), with a corresponding anode potential (E(an)) range of -188 to -4 mV (versus a standard hydrogen electrode [SHE]). For glucose-fed MFCs (glucose-fed reactors [GRs]), I ranged from 40.0 mA/m(2) (9,800 Ω) to 273.0 mA/m(2) (150 Ω), with a corresponding E(an) range of -189 to -7 mV. ARs produced higher Coulombic efficiencies and energy efficiencies than GRs over all tested R(ext) levels because of electron and potential losses from glucose fermentation. Biogas production accounted for 14 to 18% of electron flux in GRs but only 0 to 6% of that in ARs. GRs produced similar levels of methane, regardless of the R(ext). However, total methane production in ARs increased as R(ext) increased, suggesting that E(an) might influence the competition for substrates between exoelectrogens and methanogens in ARs. An increase of R(ext) to 9,800 Ω significantly changed the anode bacterial communities for both ARs and GRs, while operating at 970 Ω and 150 Ω had little effect. Deltaproteobacteria and Bacteroidetes were the major groups found in anode communities in ARs and GRs. Betaproteobacteria and Gammaproteobacteria were found only in ARs. Bacilli were abundant only in GRs. The anode-methanogenic communities were dominated by Methanosaetaceae, with significantly lower numbers of Methanomicrobiales. These results show that R(ext) affects not only the E(an) and current generation but also the anode biofilm community and methanogenesis.
Collapse
|
274
|
Wagner RC, Call DF, Logan BE. Optimal set anode potentials vary in bioelectrochemical systems. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:6036-41. [PMID: 20704197 DOI: 10.1021/es101013e] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
In bioelectrochemical systems (BESs), the anode potential can be set to a fixed voltage using a potentiostat, but there is no accepted method for defining an optimal potential. Microbes can theoretically gain more energy by reducing a terminal electron acceptor with a more positive potential, for example oxygen compared to nitrate. Therefore, more positive anode potentials should allow microbes to gain more energy per electron transferred than a lower potential, but this can only occur if the microbe has metabolic pathways capable of capturing the available energy. Our review of the literature shows that there is a general trend of improved performance using more positive potentials, but there are several notable cases where biofilm growth and current generation improved or only occurred at more negative potentials. This suggests that even with diverse microbial communities, it is primarily the potential of the terminal respiratory proteins used by certain exoelectrogenic bacteria, and to a lesser extent the anode potential, that determines the optimal growth conditions in the reactor. Our analysis suggests that additional bioelectrochemical investigations of both pure and mixed cultures, over a wide range of potentials, are needed to better understand how to set and evaluate optimal anode potentials for improving BES performance.
Collapse
Affiliation(s)
- Rachel C Wagner
- Department of Civil and Environmental Engineering, 212 Sackett Building, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | | | | |
Collapse
|
275
|
Liu H, Newton G, Nakamura R, Hashimoto K, Nakanishi S. Electrochemical Characterization of a Single Electricity-Producing Bacterial Cell of Shewanella by Using Optical Tweezers. Angew Chem Int Ed Engl 2010; 49:6596-9. [DOI: 10.1002/anie.201000315] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
276
|
Liu H, Newton G, Nakamura R, Hashimoto K, Nakanishi S. Electrochemical Characterization of a Single Electricity-Producing Bacterial Cell of Shewanella by Using Optical Tweezers. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201000315] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
277
|
Katuri KP, Scott K. Electricity generation from the treatment of wastewater with a hybrid up-flow microbial fuel cell. Biotechnol Bioeng 2010; 107:52-8. [DOI: 10.1002/bit.22778] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
278
|
Wei J, Liang P, Cao X, Huang X. A new insight into potential regulation on growth and power generation of Geobacter sulfurreducens in microbial fuel cells based on energy viewpoint. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:3187-3191. [PMID: 20345152 DOI: 10.1021/es903758m] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The anode potential in microbial fuel cells (MFCs) defines the possible metabolic energy gain (PMEG) for the bacteria growth. This study focused on the mechanism behind anode potential controlling microbial growth and power generation in MFCs from an energy perspective. Four sets of MFCs were operated with varied conditions: three with different applied anode potential (-160, 0, and 400 mV vs standard hydrogen electrode (SHE)) and one with an external resistor (500 Omega). A model strain Geobacter sulfurreducens was used here. The evolution of biomass was measured and its quantitative relationship with PMEG was analyzed. Linear voltammetry and cyclic voltammetry were also carried out. Results indicated a notable gain in biomass and power density when anode potential increased from -160 to 0 mV. However, no gain in biomass and power generation was detected when anode potential further increased to 400 mV. At anode potential of 0 mV and below, G. sulfurreducens extracted a significant portion of PMEG for growth, while utilization of PMEG significantly decreased at 400 mV. Furthermore, the anode potential has a minor influence on individual G. sulfurreducens cell activity, and the maximum power density of MFC proportionate to biomass.
Collapse
Affiliation(s)
- Jincheng Wei
- State Key Joint Laboratory of Environment Simulation and Pollution Control Department of Environmental Science and Engineering Tsinghua University, Beijing, 100084, P.R. China
| | | | | | | |
Collapse
|
279
|
Torres CI, Marcus AK, Lee HS, Parameswaran P, Krajmalnik-Brown R, Rittmann BE. A kinetic perspective on extracellular electron transfer by anode-respiring bacteria. FEMS Microbiol Rev 2010; 34:3-17. [DOI: 10.1111/j.1574-6976.2009.00191.x] [Citation(s) in RCA: 446] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
|