Evaluating a multi-panel air cathode through electrochemical and biotic tests

WATER RESEARCH

卷:148

Article

Rossi, Ruggero¹  Jones, David¹  Myung, Jaewook²  Zikmund, Emily¹  Yang, Wulin¹  Gallego, Yolanda Alvarez³  Pant, Deepak³  Evans, Patrick J.⁴  Page, Martin A.⁵  Cropek, Donald M.⁵  Logan, Bruce E.¹ 

[1] Penn State Univ, Dept Civil & Environm Engn, University Pk, PA 16802 USA

[2] Southern Methodist Univ, Dept Civil & Environm Engn, Bhubaneswar 752050, Odisha, India

[3] Flemish Inst Technol Res VITO, Separat & Convers Technol, Boeretang 200, B-2400 Mol, Belgium

[4] CDM Smith, Bellevue, WA 98007 USA

[5] US Army, Corps Engineers, Engineer Res & Dev Ctr, Construct Engn Res Lab, Champaign, IL 61822 USA

关键词: MFC;    Scaling up;    Wastewater;    Chronopotentiometry;    Air cathode;   

DOI  :  10.1016/j.watres.2018.10.022

来源: Elsevier

【 摘 要 】

To scale up microbial fuel cells (MFCs), larger cathodes need to be developed that can use air directly, rather than dissolved oxygen, and have good electrochemical performance. A new type of cathode design was examined here that uses a window-pane approach with fifteen smaller cathodes welded to a single conductive metal sheet to maintain good electrical conductivity across the cathode with an increase in total area. Abiotic electrochemical tests were conducted to evaluate the impact of the cathode size (exposed areas of 7 cm(2), 33 cm(2), and 6200 cm(2)) on performance for all cathodes having the same active catalyst material. Increasing the size of the exposed area of the electrodes to the electrolyte from 7 cm(2) to 33 cm(2) (a single cathode panel) decreased the cathode potential by 5%, and a further increase in size to 6200 cm(2) using the multi-panel cathode reduced the electrode potential by 55% (at 0.6 A m(-2)), in a 50 mM phosphate buffer solution (PBS). In 85 L MFC tests with the largest cathode using wastewater as a fuel, the maximum power density based on polarization data was 0.083 +/- 0.006 W m(-2) using 22 brush anodes to fully cover the cathode, and 0.061 +/- 0.003 W m(-2) with 8 brush anodes (40% of cathode projected area) compared to 0.304 +/- 0.009 W m(-2) obtained in the 28 mL MFC. Recovering power from large MFCs will therefore be challenging, but several approaches identified in this study can be pursued to maintain performance when increasing the size of the electrodes. (C) 2018 Elsevier Ltd. All rights reserved.

【 授权许可】

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