High rate membrane-less microbial electrolysis cell for continuous hydrogen production. Int J Hydrogen Energ

Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, QC H2P 2R2, Canada
International Journal of Hydrogen Energy (Impact Factor: 3.31). 01/2009; 34(2):672-677. DOI: 10.1016/j.ijhydene.2008.11.003

ABSTRACT This study demonstrates hydrogen production in a membrane-less continuous flow microbial electrolysis cell (MEC) with a gas-phase cathode. The MEC used a carbon felt anode and a gas diffusion cathode with a Pt loading of 0.5 mg cm−2. No proton exchange membrane (PEM) was used in the setup. Instead, the electrodes were separated by a J-cloth. The absence of a PEM as well as a short distance maintained between the electrodes (0.3 mm) resulted in a low internal resistance of 19 Ω. Due to an improved design, the volumetric hydrogen production rate reached 6.3 LSTP d−1. In spite of the PEM absence, methane concentration in the gas collection chamber was below 2.1% and the presence of hydrogen in the anodic chamber was never observed.

1 Follower
60 Reads
  • Source
    • "The electrons flow to the cathode through an external wire and combine with protons to form H 2 . The additional energy needed is supplied by an external power supply (Tartakovsky et al. 2009). Although the performance of MECs has improved significantly in recent years, their tests have been limited to the laboratory. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The use of commercial electrodes as cathodes in a single-chamber microbial electrolysis cell has been investigated. The cell was operated in sequencing batch mode and the performance of the electrodes was compared with carbon cloth containing 0.5 mg Pt cm(-2). Overall H2 recovery [Formula: see text] was 66.7 ± 1.4, 58.7 ± 1.1 and 55.5 ± 1.5 % for Pt/CC, Ni and Ti mesh electrodes, respectively. Columbic efficiencies of the three cathodes were in the same range (74.8 ± 1.5, 77.6 ± 1.7 and 75.7 ± 1.2 % for Pt/CC, Ni and Ti mesh electrodes, respectively). A similar performance for the three cathodes under near-neutral pH and ambient temperature was obtained. The commercial electrodes are much cheaper than carbon cloth containing Pt. Low cost and good performance of these electrodes suggest they are suitable cathode materials for large scale application.
    Biotechnology Letters 06/2014; 36(10). DOI:10.1007/s10529-014-1565-7 · 1.59 Impact Factor
  • Source
    • "Alternatively, it was recently discovered that this thermodynamic barrier may be overcome by means of a small input of electrical energy (Liu et al., 2005b; Rozendal and Buisman, 2005; Rozendal et al., 2006b) in what has been called a microbial electrolysis cell (MEC). More recent developments in bioelectrochemical systems (BESs) suggest that MECs may represent a promising technology for combining wastewater treatment and energy recovery (Ditzig et al., 2007; Logan et al., 2008; Rozendal et al., 2008a,b; Tartakovsky et al., 2009; Pinto et al., 2011) by using the wastewater stream as a free electron supply. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Globally, large amounts of electrical energy are spent every year for domestic wastewater (dWW) treatment. In the future, energy prices are expected to rise as the demand for energy resources increases and fossil fuel reserves become depleted. By using appropriate technologies, the potential chemical energy contained in the organic compounds present in dWWs might help to improve the energy and economic balance of dWW treatment plants. Bioelectrochemical Systems (BESs) in general and microbial electrolysis cells (MECs) in particular represent an emerging technology capable of harvesting part of this energy. This study offers an overview of the potential of using MEC technology in dWW treatment plants (dWWTPs) to reduce the energy bill. It begins with a brief account of the basics of BESs, followed by an examination of how MECs can be integrated in dWW treatment plants (dWWTPs), identifying scaling-up bottlenecks and estimating potential energy savings. A simplified analysis showed that the use of MEC technology may help to reduce up to ~20% the energy consumption in a conventional dWWTP. The study concludes with a discussion of the future perspectives of MEC technology for dWW treatment. The growing rates of municipal water and wastewater treatment markets in Europe offer excellent business prospects and it is expected that the first generation of MECs could be ready within 1-4 years. However, before MEC technology may achieve practical implementation in dWWTPs, it needs not only to overcome important techno-economic challenges, but also to compete with other energy-producing technologies.
    Frontiers in Energy Research 06/2014; 2(19). DOI:10.3389/fenrg.2014.00019
  • Source
    • "Oxygen is considered to be the most useful electron acceptor for practical applications of MFCs due to its abundance and high redox potential (Freguia et al. 2008). Two-chamber MFCs contain a membrane which result in pH gradients that can affect performance, and the catholyte needs to be aerated, which requires a high energy input (Clauwaert and Verstraete 2009; Tartakovsky et al. 2009). The use of single chamber, air-cathode designs avoids the need for a membrane or catholyte aeration, and avoids development of large pH changes. "
    [Show abstract] [Hide abstract]
    ABSTRACT: A large percentage of organic fuel consumed in a microbial fuel cell (MFC) is lost as a result of oxygen transfer through the cathode. In order to understand how this oxygen transfer affects the microbial community structure, reactors were operated in duplicate using three configurations: closed circuit (CC; with current generation), open circuit (OC; no current generation), and sealed off cathodes (SO; no current, with a solid plate placed across the cathode). Most (98 %) of the chemical oxygen demand (COD) was removed during power production in the CC reactor (maximum of 640 ± 10 mW/m(2)), with a low percent of substrate converted to current (coulombic efficiency of 26.5 ± 2.1 %). Sealing the cathode reduced COD removal to 7 %, but with an open cathode, there was nearly as much COD removal by the OC reactor (94.5 %) as the CC reactor. Oxygen transfer into the reactor substantially affected the composition of the microbial communities. Based on analysis of the biofilms using 16S rRNA gene pyrosequencing, microbes most similar to Geobacter were predominant on the anodes in the CC MFC (72 % of sequences), but the most abundant bacteria were Azoarcus (42 to 47 %) in the OC reactor, and Dechloromonas (17 %) in the SO reactor. Hydrogenotrophic methanogens were most predominant, with sequences most similar to Methanobacterium in the CC and SO reactor, and Methanocorpusculum in the OC reactors. These results show that oxygen leakage through the cathode substantially alters the bacterial anode communities, and that hydrogenotrophic methanogens predominate despite high concentrations of acetate. The predominant methanogens in the CC reactor most closely resembled those in the SO reactor, demonstrating that oxygen leakage alters methanogenic as well as general bacterial communities.
    Applied Microbiology and Biotechnology 06/2013; 97(22). DOI:10.1007/s00253-013-5025-4 · 3.34 Impact Factor
Show more


60 Reads
Available from