不同基质碳源下人工湿地微生物燃料电池的电化学性能及微生物群落结构

Electrochemical properties and microbial community structure of constructed wetland microbial fuel cell under different matrix carbon source

通过设计一种下流式人工湿地微生物燃料电池(CW-MFC)系统,研究了以葡萄糖(S.G.)和乙酸钠(S.S.)为基质碳源时系统的电化学性能及其微生物群落结构,揭示了该系统在不同基质碳源下的产电特性。结果表明,S.S.发电电压可达483 mV,最大功率密度为48.14 mW·m^(-2),优于S.G.(42.61 mW·m^(-2))。S.S.对水体COD的去除率比S.G.(70.1%)高出5%。电化学性能表征结果表明,S.S.比S.G.具有更快的电子转移能力,S.S.的电荷转移电阻(45.2Ω)小于S.G.(197Ω)。与S.G.相比,在S.S.中发现Clostridium_sensu_stricto_1(梭状芽胞杆菌)和Pseudomonas(假单胞菌)丰度的降低,Acinetobacter(不动杆菌)、Acetobacteroides(类醋酸杆菌)、Lactococcus(乳球菌)和Geobacter(地杆菌)丰度的升高。此外,结合FAPROTAX预测结果可知,与发电有关细菌的相对丰度在S.S.中高于S.G.。以上研究结果证明了乙酸钠可作为CW-MFC基质碳源的潜力,同时本研究设计的下流式CWMFC系统有助于为后续污染水体的治理提供参考。

For revealing the electricity generation and other characteristics of downflow constructed wetland microbial fuel cell(CW-MFC),it is needed to identify the electricity generation voltage,output power density,electrochemical performance,microbial community structure and FAPROTAX prediction result of downflow CW-MFC.In this study,the electrochemical properties and microbial community structure of downflow CWMFC under the matrix carbon source of glucose(S.G.)and sodium acetate(S.S.)were compared.The results indicates that the electricity generation voltage of S.S.could reach 483 mV,and the maximum power density was 48.14 mW·m^(-2),which was higher than S.G.(42.61 mW·m^(-2)).The COD removal rate of S.S.was 5%higher than that of S.G.(70.1%).Electrochemical performance indicates that the S.S.had a faster electron transferability compared with S.G.The charge transfer resistance of S.S.(45.2Ω)was lower than that of S.G.(197Ω).Compared with S.G.based CW-MFC,a decreased abundance of Clostridium_sensu_stricto_1 and Pseudomonas,and accompanied by an increase of Acinetobacter,Acetobacteroides,Lactococcus and Geobacter occurred in the S.S.based CW-MFC.The relative abundance of bacteria associated with electricity generation in S.S.was higher than that in S.G.,which was found by the results of FAPROTAX prediction.The potential of sodium acetate as matrix carbon source for CW-MFC was confirmed.At the same time,this study can provide a reference for the follow-up research on the electricity generation and polluted water treatment by this designed downflow CW-MFC system.