Cathodic biofouling control by microbial separators in air-breathing microbial fuel cells  

作　　者：Chao Li Kexin Yi Shaogang Hu Wulin Yang 

机构地区：[1]College of Environmental Science and Engineering,Peking University,No.5 Yiheyuan Road,Haidian District,Beijing,100871,China

出　　处：《Environmental Science and Ecotechnology》2023年第3期35-43,共9页环境科学与生态技术（英文）

基　　金：supported by the National Nature Science Foundation of China(Grant No.52100021);the China Postdoctoral Science Foundation(Grants No.2022M720004 and No.2022M710208)。

摘　　要：Microbial fuel cells(MFCs)incorporating air-breathing cathodes have emerged as a promising ecofriendly wastewater treatment technology capable of operating on an energy-free basis.However,the inevitable biofouling of these devices rapidly decreases cathodic catalytic activity and also reduces the stability of MFCs during long-term operation.The present work developed a novel microbial separator for use in air-breathing MFCs that protects cathodic catalytic activity.In these modified devices,microbes preferentially grow on the microbial separator rather than the cathodic surface such that biofouling is prevented.Trials showed that this concept provided low charge transfer and mass diffusion resistance values during the cathodic oxygen reduction reaction of 4.6±1.3 and 17.3±6.8 U,respectively,after prolonged operation.The maximum power density was found to be stable at 1.06±0.07 W m2 throughout a long-term test and the chemical oxygen demand removal efficiency was increased to 92%compared with a value of 83%for MFCs exhibiting serious biofouling.In addition,a cathode combined with a microbial separator demonstrated less cross-cathode diffusion of oxygen to the anolyte.This effect indirectly induced the growth of electroactive bacteria and produced higher currents in air-breathing MFCs.Most importantly,the present microbial separator concept enhances both the lifespan and economics of air-breathing MFCs by removing the need to replace or regenerate the cathode during longterm operation.These results indicate that the installation of a microbial separator is an effective means of stabilizing power generation and ensuring the cost-effective performance of air-breathing MFCs intended for future industrial applications.

关 键 词：Air-breathing MFC Microbial separator Niche-selective superiority Biofouling elimination Stability and sustainability 

分 类 号：X701[环境科学与工程—环境工程]