Improving phosphate buffer-free cathode performance of microbial fuel cell based on biological nitrification.
Improving phosphate buffer-free cathode performance of microbial fuel cell based on biological nitrification.
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DOI：
10.1016/j.bios.2009.05.015
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发表时间：
2009-08
影响因子：
12.6
通讯作者：
S. You;N. Ren;Q. Zhao;P. Kiely;Jing‐Yuan Wang;Fenglin Yang;L. Fu;Luo Peng
中科院分区：
文献类型：
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作者：
S. You;N. Ren;Q. Zhao;P. Kiely;Jing‐Yuan Wang;Fenglin Yang;L. Fu;Luo Peng
为了减少目前微生物燃料电池（MFC）中使用的磷酸盐缓冲液的量，我们研究了在没有磷酸盐缓冲液的情况下阴极生物硝化的作用。在阴极室中加入硝化混合菌群（NMC）和提高阴极液中铵离子浓度，使槽电压从0.3V提高到0.567V（外电阻为100Ω），阴极液pH从8.8降低到7.05。大部分铵被氧化为亚硝酸盐，如硝酸盐氮（NO3−-N）的增加所示。在阴极液中添加94.2mgN/l的NH 4+时，MFC的最大输出功率为2.1±0.14mW（10.94±0.73W/m3）。这与提供有缓冲或非缓冲溶液的MFC相比是有利的。无缓冲液的NMC接种阴极室显示出最小的极化电阻，表明硝化导致改善的阴极性能。无磷酸盐缓冲剂的阴极和电池的性能的改善与生物硝化正相关，其中我们建议由铵氧化产生的额外质子促进阴极处的氧的电化学还原。
To reduce the amount of phosphate buffer currently used in Microbial Fuel Cell's (MFC's), we investigated the role of biological nitrification at the cathode in the absence of phosphate buffer. The addition of a nitrifying mixed consortia (NMC) to the cathode compartment and increasing ammonium concentration in the catholyte resulted in an increase of cell voltage from 0.3V to 0.567V (external resistance of 100Ω) and a decrease of catholyte pH from 8.8 to 7.05. A large fraction of ammonium was oxidized to nitrite, as indicated by an increase of nitrate-nitrogen (NO3−–N). An MFC inoculated with an NMC and supplied with 94.2mgN/l ammonium to the catholyte could generate a maximum power of 2.1±0.14mW (10.94±0.73W/m3). This compared favorably to an MFC supplied with either buffered or non-buffered solution. The buffer-free NMC inoculated cathodic chamber showed the smallest polarization resistance, suggesting that nitrification resulted in improved cathode performance. The improved performances of the phosphate buffer-free cathode and cell are positively related to biological nitrification, in which we suggest additional protons produced from ammonium oxidation facilitated electrochemical reduction of oxygen at cathode.