文献类型：期刊文献

英文题名：Mechanistic investigation of U(VI) sequestration by zero-valent iron/activated carbon composites

作者：Wang, Min[1];Cheng, Wen[1];Wan, Tian[1];Hu, Baowei[2];Zhu, Yuling[2];Song, Xiaofei[3];Sun, Yubing[4]

机构：[1]Xian Univ Technol, State Key Lab Ecohydraul Northwest Arid Reg, Xian 710048, Shanxi, Peoples R China;[2]Shaoxing Univ, Sch Life Sci, Huancheng West Rd 508, Shaoxing 312000, Peoples R China;[3]South China Univ Technol, Sch Environm & Energy, Guangzhou 510006, Guangdong, Peoples R China;[4]North China Elect Power Univ, Coll Environm Sci & Engn, Beijing, Peoples R China

年份：2019

卷号：362

起止页码：99

外文期刊名：CHEMICAL ENGINEERING JOURNAL

收录：SCI-EXPANDED(收录号：WOS:000457863500011)、、EI(收录号：20190206364758)、Scopus(收录号：2-s2.0-85059671233)、WOS

基金：This work was supported by the National Nature Science Foundation of China (No. 51829211; 51709224; 21876115), National Natural Science Foundation-Outstanding Youth Foundation (No. 21822602) and China Postdoctoral Science Foundation (2018 M633548).

语种：英文

外文关键词：U(VI); ZVI; Activated carbon; EXAFS; Interaction mechanism

外文摘要：Mechanistic investigation of U(VI) removal on zero-valent iron/activated carbon (ZVI/AC) was elucidated by batch, X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge structure (XANES) and extended Xray absorption fine structure (EXAFS) techniques. Batch experiments showed that U(VI) removal on ZVI/AC was significantly higher than that of ZVI, whereas the reduction of U(VI) on ZVI was slightly higher than that of ZVI/AC under reaction time of 12 h. No influence of carbonate on U(VI) removal by ZVI/AC was observed at pH < 5.0, whereas U(VI) removal on ZVI at pH < 5.0 was significantly enhanced with increasing carbonate concentration due to the electrostatic attraction of positive charge of ZVI/AC and negative uranyl-carbonate complexes such as UO2CO3(aq)/UO2(CO3)(2)(2-) species. The ZVI/AC composites displayed the high adsorption capacity and good recycle performance. The high adsorption performance of AC and strong redox capacity of ZVI were responsible for U(VI) removal by XPS and XANES analysis. The corrosion products of ZVI/AC were transferred from magnetite into goethite with increasing reaction time by analysis of XRD pattern. According to EXAFS analysis, the bonding distance of U-U shell for ZVI was slightly shorter than that of ZVI/AC, indicating that redox and adsorption was mainly interaction mechanism of U(VI) on ZVI and ZVI/AC, respectively. These findings are crucial for the application of ZVI-based composites for U(VI) removal in actual environmental remediation.