Lu Yao, Liu Lijie, Zhang Xiaoqian, Zhao Tianyu, Jin Yi, Zhang Yongqing, Huang Shaobin
School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, China.
State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China.
Bioresour Technol. 2023 Nov;387:129690. doi: 10.1016/j.biortech.2023.129690. Epub 2023 Aug 17.
The electrochemical performances and denitrification efficiency of microbial fuel cells (MFCs) are often limited by chemical oxygen demand/nitrogen (COD/N) of wastewater. To overcome this limitation, single-chamber air cathode MFCs with varying COD/N (16/1, 8/1, and 4/1) were established to investigate their electrochemical performances, denitrification efficiency, and bacterial communities. The optimal COD/N for maximizing electricity generation and denitrification efficiency was 8/1, as supported by the greatest corrected coulomb efficiency (13.6%) and electron transfer rate (2.36 C/h for electricity generation, 39.77 C/h for denitrification). As COD/N decreased, the electrochemically active genus Geobacter was replaced by the denitrifying genera Un._f_Burkholderiaceae, Dechlorosoma, and Petrimonas. These results indicated that the efficiency of electricity generation and denitrification was not solely determined by the abundance of electrochemically active and denitrifying bacteria. The presence of a faster electron transfer pathway, possibly direct interspecies electron transfer, enhanced simultaneous electricity generation and denitrification in MFCs with COD/N of 8/1.
微生物燃料电池（MFCs）的电化学性能和反硝化效率常常受到废水化学需氧量/氮（COD/N）的限制。为克服这一限制，建立了具有不同COD/N（16/1、8/1和4/1）的单室空气阴极MFCs，以研究其电化学性能、反硝化效率和细菌群落。使发电和反硝化效率最大化的最佳COD/N为8/1，这得到了最大校正库仑效率（13.6%）和电子转移速率（发电为2.36 C/h，反硝化为39.77 C/h）的支持。随着COD/N的降低，具有电化学活性的地杆菌属被反硝化菌属Un._f_Burkholderiaceae、脱氯菌属和Petrimonas所取代。这些结果表明，发电和反硝化效率并非仅由具有电化学活性和反硝化细菌的丰度决定。在COD/N为8/1的MFCs中，存在更快的电子转移途径，可能是直接种间电子转移，增强了同步发电和反硝化。
