土著菌群还原矿化修复铀污染地下水  

Bioreduction and biomineralization of indigenous bacteria for the remediation of uranium-contaminated groundwater

作　　者：王国华 刘颖[1] 王家莉 向金晶 刘迎九 赵发 刘金香[1,2] Guohua WANG;Ying LIU;Jiali WANG;Jinjing XIANG;Yingjiu LIU;Fa ZHAO;Jinxiang LIU(School of Civil Engineering,University of South China,Hengyang,Hunan 421001,China;Hunan Province Key Laboratory of Pollution Control and Resources Reuse Technology,University of South China,Hengyang,Hunan 421001,China;CNNC 272 Uranium Industry Co.,Ltd.,Hengyang,Hunan 421000,China)

机构地区：[1]南华大学土木工程学院,湖南衡阳421001 [2]南华大学污染控制与资源化技术湖南省高校重点实验室,湖南衡阳421001 [3]中核二七二铀业有限责任公司,湖南衡阳421000

出　　处：《过程工程学报》2023年第1期88-97,共10页The Chinese Journal of Process Engineering

基　　金：生物还原耦合生物矿化修复含铀地下水的机理及强化机制(编号:51904155);高效还原菌群构建及其修复酸性含铀地下水的协同机制研究(编号:2020JJ5492);湖南省大学生创新创业训练计划项目(编号:湘教通[2020]191号)。

摘　　要：本实验研究了β-甘油磷酸钠刺激下土著菌群对中性含铀模拟地下水的处理效果及机理。结果表明,β-甘油磷酸钠可同时激活生物还原和生物矿化菌群,其对铀的去除率达98%以上,微生物表面均匀沉积CaU(PO_(4))_(2)和Mg(UO_(2))_(2)(PO_(4))_(2)·10H2_(O)等鳞片状矿物。土著菌群还原矿化铀的机理为:反应前期生物还原和生物矿化同时参与了铀的固定,且以生物矿化作用为主,Dysgonomonas,Propionispora,Macellibacteroides,unclassified_Rhizobiaceae和unclassified_Rhodocyclacea可能参与了溶液中U(Ⅵ)的还原,Acinetobacter促进生物矿化的发生;随后在Methyloversatilis和unclassified_Enterobacteriaceae的作用下,部分矿化生成的U(Ⅵ)沉淀被微生物逐渐还原成U(Ⅳ)沉淀。本实验为今后微生物治理铀污染地下水的长效性能强化策略研究提供了新的理论支撑。In recent years,microbial technology for remediation of uranium-contaminated groundwater has attracted the attention of scholars,because of its advantages of low cost,self-reproduction,no ease to cause secondary contamination,and less disturbance to the environment.The mechanisms of microbial remediation include biosorption,bioaccumulation,bioreduction,and biomineralization.Among them,bioreduction and biomineralization were two promising methods that could be utilized in situ shortly.Previous studies had shown that adding organophosphate compound to uraniumcontaminated groundwater may give rise to remediation mechanisms such as bioreduction and biomineralization.To explore the coupling mechanisms of these two methods mediated by the indigenous microorganism,β-glycerol phosphate disodium salt was added in this study to stimulate the indigenous microorganism to treat neutral artificial uranium-containing groundwater.In the control group,glycerol was added to stimulate the bioreduction activity of the microbes only.The results showed that the removal rate of uranium in the experimental group was more than 98%,and the removal efficiency and effect were better than that of the control group under the same condition.After 21 days of the experiment,the scale-like precipitation on the cell surface could be observed via SEM.XRD analysis confirmed that the products were CaU(PO_(4))_(2)and Mg(UO_(2))_(2)(PO_(4))_(2)·10H2_(O),which possessed excellent resistance against reoxidation.XPS also indicated the presence of U(IV)and U(VI)in the products.Mechanism analysis showed thatβ-Glycerol phosphate disodium salt activated both bioreduction and biomineralization microbial community.Dysgonomonas,Propionispora,Macellibacteroides,unclassified_Rhizobiaceae and unclassified_Rhodocyclacea may be involved in the reduction of U(Ⅵ),NO3-,and SO42-,and Acinetobacter facilitated the process of biomineralization.while Methyloversatilis and unclassified_Enterobacteriaceae may take part in the reduction of U(Ⅵ)-phosphate minerals.In the

关 键 词：土著菌群 铀 生物还原 生物矿化 机理分析 

分 类 号：X172[环境科学与工程—环境科学] X523