摘要
在电子中介体蒽醌-2-磺酸钠(AQS)存在条件下,探讨了革兰氏阳性兼性厌氧菌(Cellulomonas sp)与单质铁(ZVI)协同作用处理水中U(Ⅵ)的效果和相应机理.实验结果表明:在厌氧环境下,单质铁与纤维单胞菌去除U(Ⅵ)存在明显的协同作用.AQS存在条件下,在24 h内、p H为7、温度为30℃时,ZVI与纤维单胞菌协同作用,U(Ⅵ)去除率为97.6%;在ZVI对照中,U(Ⅵ)去除率仅为11.7%.在无细胞对照组中未观察到U(Ⅵ)减少.Cu2+、Ca2+等离子的共存对U(Ⅵ)去除有明显的抑制作用,与其他离子相比,Mn2+、Cr6+的抑制作用较小.SEM-EDS分析表明,纤维单胞菌去除U(Ⅵ)后表面形态发生了改变,菌体表面形成了较多不规则突起且菌体表面覆盖有铀沉淀物.XPS结果表明:铀与纤维单胞菌相互作用后以U(Ⅳ)和U(Ⅵ)的混合物存在.通过XPS的峰面积计算,纤维单胞菌还原U(Ⅵ)后,U(Ⅳ)和U(Ⅵ)的含量分别为61.9%和38.1%,且溶液中的铀大部分是稳定的UO2.
In this study,the synergistic effect and its corresponding mechanism of gram-positive facultative anaerobic bacteria（Cellulomonas sp） and zero-valent iron（ZVI） has on thetreatment of U（Ⅵ） in aqueous solution was studied in the presence of an electronic intermediate sodium arsenide-2-sulfonate（AQS）.Experiments show that under anaerobic conditions,there is a significant synergistic effect of ZVI and Cellulomonas sp in the reduction of U（Ⅵ）.Using AQS as an electron shuttle vector,Cellulomonas sp utilizes electron donors to efficiently reduce U（Ⅵ）.Within 24 hours,when the p H was 7 and temperature was 30 ℃,ZVI and Cellulomonas sp come into synergistic reaction,and the U（Ⅵ） removal rate was up to 97.6%,while in the ZVI control group,the U（Ⅵ） removal rate was only 11.7%.No U（Ⅵ）reduction was observed in the cell-free control group.The coexistence of Cu^（2＋） and Ca^（2＋） ions has obvious inhibitory effect on U（Ⅵ） reduction.Compared with other ions,the inhibition effect of Mn^（2＋） and Cr^（6＋） is much smaller.Scanning electron icroscopy（SEM） and energy dispersive pectrometer（EDS） results showed that,after the Cellulomonas sp reduced the U（Ⅵ）,the surface of Cellulomonas sp has changed,namely,there were many irregular protrusions formed on the surface of the bacteria and covered with uranium deposits.And the uranium element was deposited in the cells of the Cellulomonas sp.XPS results showed that after the interaction of uranium and Cellulomonas SP,they exist as a mixture of U（Ⅵ） and U（Ⅳ）.Through the calculation of the peak area of XPS,the contents of U（Ⅳ） and U（Ⅵ）were 61.9% and 38.1% respectively after the interaction.And most of the uranium in the solution is stable UO2.
作者
周佳权
谢水波
荣丽杉
杨金辉
刘迎九
ZHOU Jiaquan 1,XIE Shuibo 1,2 ,RONG Lishan 1,YANG Jinhui 1,LIU Yingjiu 1(1.Hunan Provincial Key Laboratory of Pollution Control and Resources Technology,University of SouthChina,Hengyang,Hunan 421001,China;2.Key Discipline Laboratory for National Defense of Biotechnologyin Uranium Mining and Hydrometallurgy,University of South China,Hengyang,Hunan 421001,Chin)
出处
《南华大学学报（自然科学版）》
2018年第4期1-7,共7页
Journal of University of South China：Science and Technology
基金
国家自然科学基金项目(11475080)
湖南省高校实验创新平台开放基金项目(16K075)
南华大学研究生科研创新项目(2017XCX14)
