Electricity generation using membrane and salt bridge microbial fuel cells
Electricity generation using membrane and salt bridge microbial fuel cells
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DOI：
10.1016/j.watres.2005.02.002
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发表时间：
2005-05-01
期刊：
影响因子：
12.8
通讯作者：
Logan, BE
中科院分区：
文献类型：
--
作者：
Min, BK;Cheng, SA;Logan, BE
微生物燃料电池（MFC）可以直接从溶解的有机物的氧化中产生电力，但是MFC的优化将需要我们更多地了解可以增加功率输出的因素，例如可以影响系统内阻的质子交换系统的类型。使用纯培养物（Geolithmetallireducens）或混合培养物（废水接种物）比较了含有质子交换膜的MFC中的功率输出。两种接种物的功率输出基本相同，G.金属还原菌和38 +/- 1 mW/m2的废水接种物。我们还研究了在MFC的功率输出与盐桥，而不是膜系统。通过盐桥MFC（接种G.金属还原物）为2.2mW/m2。低功率输出直接归因于基于使用阻抗谱的测量的盐桥系统的内阻（19920 +/-50 Ω）比膜系统的内阻（1286 +/-1 Ω）高。在这两个系统中，观察到从阴极室到阳极室的氧扩散是发电的一个因素。使用氮气鼓泡、L-半胱氨酸（化学氧清除剂）或悬浮细胞（生物氧清除剂）来限制气体扩散到阳极室中的影响。例如，与没有气体喷射的情况下获得的库仑效率（19%）相比，氮气喷射增加了总体库仑效率（47%或55%）。这些结果表明，增加MFC中的功率密度将需要降低系统的内阻，并且需要控制溶解氧流入阳极室的方法以增加总体库仑效率。(c)2005爱思唯尔有限公司保留所有权利。
Microbial fuel cells (MFCs) can be used to directly generate electricity from the oxidation of dissolved organic matter, but optimization of MFCs will require that we know more about the factors that can increase power output such as the type of proton exchange system which can affect the system internal resistance. Power output in a MFC containing a proton exchange membrane was compared using a pure culture (Geobacter metallireducens) or a mixed culture (wastewater inoculum). Power output with either inoculum was essentially the same, with 40 +/- 1 mW/m(2) for G. metallireducens and 38 +/- 1 mW/m(2) for the wastewater inoculum. We also examined power output in a MFC with a salt bridge instead of a membrane system. Power output by the salt bridge MFC (inoculated with G. metallireducens) was 2.2 mW/m(2). The low power output was directly attributed to the higher internal resistance of the salt bridge system (19920 +/- 50 Omega) compared to that of the membrane system (1286 +/- 1 Omega) based on measurements using impedance spectroscopy. In both systems, it was observed that oxygen diffusion from the cathode chamber into the anode chamber was a factor in power generation. Nitrogen gas sparging, L-cysteine (a chemical oxygen scavenger), or suspended cells (biological oxygen scavenger) were used to limit the effects of gas diffusion into the anode chamber. Nitrogen gas sparging, for example, increased overall Coulombic efficiency (47% or 55%) compared to that obtained without gas sparging (19%). These results show that increasing power densities in MFCs will require reducing the internal resistance of the system, and that methods are needed to control the dissolved oxygen flux into the anode chamber in order to increase overall Coulombic efficiency. (c) 2005 Elsevier Ltd. All rights reserved.