铁还原菌Escherichia sp.F1耦合工业铁粉对模拟地下水中三氯乙烯的降解  

Degradation of trichloroethylene in simulated groundwater by the ironreducing bacterium Escherichia sp.F1 coupled with industrial iron powder

作　　者：牛韩宇 吴志能 王姣 马小东 NIU Hanyu;WU Zhineng;WANG Jiao;MA Xiaodong(School of Energy and Environmental Engineering Hebei University of Technology,Tianjin 300401,China)

机构地区：[1]河北工业大学能源与环境工程学院,天津300401

出　　处：《环境工程学报》2025年第2期426-436,共11页Chinese Journal of Environmental Engineering

基　　金：国家重点研发计划项目(2020YFC1808603);河北省省级科技计划资助项目(22374206D,21374204D);国家自然科学基金青年科学基金项目(22106037);河北省自然科学基金青年科学基金项目(B2024202024)。

摘　　要：三氯乙烯(trichloroethylene,TCE)是地下水中检出较多的一种有机污染物。针对工业铁粉表面覆盖的氧化物钝化层阻碍其还原组分释放,导致对地下水中TCE还原净化效果差的问题,构建“铁还原菌-工业铁粉”耦合净化技术,以提升对模拟地下水中TCE的降解效果。从氯代烃污染土壤中富集分离新型铁还原菌,采用单因素实验探究铁还原菌耦合工业铁粉对TCE的最优降解条件,在最优降解条件下阐明耦合降解机制。结果表明,分离得到的铁还原菌Escherichia sp.F1具有高效的Fe(Ⅲ)还原能力,可还原生成质量浓度达(270.90±6.86)mg·L^(-1)的Fe(Ⅱ),且在15 d内表现出持续的铁还原能力。在最优降解条件下(pH 7,铁还原菌接种量:10%v:v,工业铁粉投加量:5 g·L^(-1),葡萄糖浓度:80 mmol·L^(-1)),反应20 d后,耦合材料对模拟地下水中TCE的降解率可达41.59%。进一步通过对耦合降解体系材料的扫描电镜、X射线能谱和X射线光电子能谱分析发现,铁还原菌F1的加入加剧了工业铁粉表面的腐蚀和钝化层被破坏,促进了其反应位点及内部还原活性组分的暴露,提升了对模拟地下水中TCE的降解效果。本研究为TCE污染地下水治理提供了一种新的方法。Trichloroethylene(TCE)is a common organic pollutant detected in groundwater.The oxide passivation layer covering the surface of industrial iron powder prevents the release of its reducing components,resulting in poor reduction and purification of TCE in groundwater.To address this issue,an"iron-reducing bacterium-industrial iron powder"coupling remediation technology was developed to improve the degradation effect of TCE in simulated groundwater.A new iron-reducing bacterium was enriched and isolated from soil contaminated with chlorinated hydrocarbon.Single-factor experiments were used to explore the optimal degradation conditions of TCE by iron-reducing bacterium coupled with industrial iron powder,and the coupled degradation mechanism was elucidated under optimal degradation conditions.The results showed that the isolated iron-reducing bacterium Escherichia sp.F1 had high Fe(Ⅲ)reduction ability which could produce Fe(Ⅱ)with a mass concentration of(270.90±6.86)mg·L^(-1),and showed sustained iron-reducing capacity within 15 days.Under optimal degradation conditions(pH 7,bacterium inoculum:10%v:v,dosage of industrial iron powder:5 g·L^(-1),glucose concentration:80 mmol·L^(-1)),the degradation rate of TCE in simulated groundwater by the coupled material could reach 41.59%in 20 days.Further analysis of the materials in the coupled degradation system using scanning electron microscopy,X-ray energy spectroscopy,and X-ray photoelectron spectroscopy demonstrated that the addition of Escherichia sp.F1 intensified the surface corrosion and destroyed the passivation layer of industrial iron powder.As a result,the reaction sites and internal reducing active components of industrial iron powder were exposed,and the degradation effect of TCE in simulated groundwater was improved.This study provides a new method for the remediation of TCE-contaminated groundwater.

关 键 词：模拟地下水 三氯乙烯 铁还原菌 工业铁粉 降解 

分 类 号：X523[环境科学与工程—环境工程]