4-氯硝基苯的电辅助微生物转化机制  

Electric-assisted microbial transformation process and mechanism of 4-chloronitrobenzene

作　　者：曹占平[1] 李岚[1] 武鑫霞 李欣航 CAO Zhan-ping;LI Lan;WU Xin-xia;LI Xin-hang(School of Environmental Science and Engineering,Tiangong University,Tianjin 300387,China)

机构地区：[1]天津工业大学环境科学与工程学院,天津300387

出　　处：《天津工业大学学报》2020年第3期48-53,共6页Journal of Tiangong University

基　　金：国家自然科学基金资助项目(51078265)。

摘　　要：针对微生物还原降解4-氯硝基苯(4-CNB)缺乏电子供体及过程缓慢的问题,将电辅助引入微生物还原降解过程,构建电辅助微生物系统(EMS);利用电辅助阴极提供低的还原电位、供电子来提升微生物的还原能力,并对4-CNB在EMS中的转化过程进行分析。结果表明:电辅助微生物体系对4-CNB降解速率常数是电催化体系(ECS)和厌氧微生物体系(MS)降解速常数之和的1.18倍。4-CNB在EMS中的还原降解分两步:首先,4-CNB中的硝基在阴极被微生物还原,生成4-氯苯胺(4-CAN)(-0.09 V.vs.SHE);而后4-CAN再还原脱氯生成苯胺(AN)(-0.42 V.vs.SHE),AN在阳极被微生物氧化降解。In view of the problem of lacking electron donor and slow process in microbial reductive degradation of 4-chloronitrobenzene(4-CNB),an electric assistance was adopted into the microbial reductive degradation process to form an electric-assisted microbial system(EMS).The electrically assisted cathode was used to provide a lower reduction potential and to provide electron to enhance the reduction capacity of microbial.And the conversion process of 4-CNB in EMS was analyzed.The results showed that the 4-CNB degradation rate constant of the EMS was 1.18 times as much as the sum of the degradation constants of the electric-catalytic system(ECS)and the microbial system(MS).The reduction of 4-CNB in EMS is divided into two steps:First,the nitro group of 4-CNB is reduced by microorganisms at the cathode to form 4-chloroaniline(4-CAN)(-0.09 V.vs.SHE),and then 4-CAN is reductively dechlorinated to form aniline(AN)(-0.42 V.vs.SHE),and AN is oxidatively degraded by microorganisms at the anode.

关 键 词：电辅助微生物系统(EMS) 4-CNB 分步还原降解 电子传递 

分 类 号：TQ151.5[化学工程—电化学工业] X703[环境科学与工程—环境工程]