Tetrachloroethane(TeCA)removal through sequential graphite-mixed metal oxide electrodes in a bioelectrochemical reactor  

作　　者：Marco Zeppilli Hafsa Yaqoubi Edoardo Dell’Armi Agnese Lai Mustapha Belfaquir Laura Lorini Marco Petrangeli Papini 

机构地区：[1]Department of Chemistry,University of Rome Sapienza,Piazzale Aldo Moro 5,Rome,00185,Italy [2]Department of Chemistry,Ibn Tofail University,Laboratory of Advanced Material and Process Engineering,Campus Universitaire,BP.242,Kenitra,Morocco

出　　处：《Environmental Science and Ecotechnology》2024年第1期59-67,共9页环境科学与生态技术（英文）

基　　金：This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 826244-ELECTRA”.Prof.Mauro Majone is acknowledged for his fruitful support during the experimental activity.

摘　　要：Electro-bioremediation offers a promising approach for eliminating persistent pollutants from groundwater since allows the stimulation of biological dechlorinating activity,utilizing renewable electricity for process operation and avoiding the injection of chemicals into aquifers.In this study,a two-chamber microbial electrolysis cell has been utilized to achieve both reductive and oxidative degradation of tetrachloroethane(TeCA).By polarizing the graphite granules cathodic chamber at650 mV vs the standard hydrogen electrode and employing a mixed metal oxide(MMO)counter electrode for oxygen production,the reductive and oxidative environment necessary for TeCA removal has been established.Continuous experiments were conducted using two feeding solutions:an optimized mineral medium for dechlorinating microorganisms,and synthetic groundwater containing sulphate and nitrate anions to investigate potential side reactions.The bioelectrochemical process efficiently reduced TeCA to a mixture of trans-dichloroethylene,vinyl chloride,and ethylene,which were subsequently oxidized in the anodic chamber with removal efficiencies of 37±2%,100±4%,and 100±5%,respectively.The introduction of synthetic groundwater with nitrate and sulphate stimulated reductions in these ions in the cathodic chamber,leading to a 17%decrease in the reductive dechlorination rate and the appearance of other chlorinated by-products,including cis-dichloroethylene and 1,2-dichloroethane(1,2-DCA),in the cathode effluent.Notably,despite the lower reductive dechlorination rate during synthetic groundwater operation,aerobic dechlorinating microorganisms within the anodic chamber completely removed VC and 1,2-DCA.This study represents the first demonstration of a sequential reductive and oxidative bioelectrochemical process for TeCA mineralization in a synthetic solution simulating contaminated groundwater.

关 键 词：Chlorinated aliphatic hydrocarbons Microbial electrolysis cells Oxidative dechlorination Reductive dechlorination Sulphate reduction Nitrate reduction 

分 类 号：X703[环境科学与工程—环境工程]