Competition for electrons between reductive dechlorination and denitrification  

作　　者：Lifeng Cao Weihua Sun Yuting Zhang Shimin Feng Jinyun Dong Yongming Zhang Bruce E. Rittmann 

机构地区：[1]Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai 200234, China [2]Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, AZ 85287-5701, USA

出　　处：《Frontiers of Environmental Science & Engineering》2017年第6期129-138,共10页环境科学与工程前沿（英文）

基　　金：Acknowledgements The authors acknowledge the financial support of the ability construction project of local Colleges and Universities in Shanghai （No. 16070503000）, Special Fund of State Key Joint Laboratory of Environment Simulation and Pollution Control （No. 16K10ESPCT）, Shanghai Gaofeng ＆ Gaoyuan Project for University Academic Program Development, and the United States National Science Foundation （No. O651794）.

摘　　要：It is common that 2,4,6-trichlorophenol （TCP） coexists with nitrate or nitrite in industrial wastewaters. In this work, simultaneous reductive dechlorination of TCP and denitrification of nitrate or nitrite competed for electron donor, which led to their mutual inhibition. All inhibitions could be relieved to a certain degree by augmenting an organic electron donor, but the impact of the added electron donor was strongest for TCP. For simultaneous reduction ofTCP together with nitrate, TCP＇s removal rate value increased 75% and 150%, respectively, when added glucose was increased from 0.4 mmol· L^-1 to 0.5 mmol· L^-1 and to 0.76 mmol· L^-1 For comparison, the removal rate for nitrate increased by only 25% and 114% for the same added glucose. The relationship between their initial biodegradation rates versus their initial concentrations could be represented well with the Monod model, which quantified their half-maximum-rate concentration （Ks value）, and Ks values for TCP, nitrate, and nitrite were larger with simultaneous reduction than independent reduction. The increases in Ks are further evidence that competition for the electron donor led to mutual inhibition. For bioremediation of wastewater containing TCP and oxidized nitrogen, both reduction reactions should proceed more rapidly if the oxidized nitrogen is nitrite instead of nitrate and if readily biodegradable electron acceptor is augmented.It is common that 2,4,6-trichlorophenol （TCP） coexists with nitrate or nitrite in industrial wastewaters. In this work, simultaneous reductive dechlorination of TCP and denitrification of nitrate or nitrite competed for electron donor, which led to their mutual inhibition. All inhibitions could be relieved to a certain degree by augmenting an organic electron donor, but the impact of the added electron donor was strongest for TCP. For simultaneous reduction ofTCP together with nitrate, TCP＇s removal rate value increased 75% and 150%, respectively, when added glucose was increased from 0.4 mmol· L^-1 to 0.5 mmol· L^-1 and to 0.76 mmol· L^-1 For comparison, the removal rate for nitrate increased by only 25% and 114% for the same added glucose. The relationship between their initial biodegradation rates versus their initial concentrations could be represented well with the Monod model, which quantified their half-maximum-rate concentration （Ks value）, and Ks values for TCP, nitrate, and nitrite were larger with simultaneous reduction than independent reduction. The increases in Ks are further evidence that competition for the electron donor led to mutual inhibition. For bioremediation of wastewater containing TCP and oxidized nitrogen, both reduction reactions should proceed more rapidly if the oxidized nitrogen is nitrite instead of nitrate and if readily biodegradable electron acceptor is augmented.

关 键 词：Competition for electrons Denitrification Reductive dechlorination Bioremediation Nitrate 2 4 6-trichlorophenol 

分 类 号：T0[一般工业技术]