文献类型：期刊文献

英文题名：Enhanced sequestration of Cr(VI) by nanoscale zero-valent iron supported on layered double hydroxide by batch and XAFS study

作者：Sheng, Guodong[1,2];Hu, Jun[4];Li, Hui[1];Li, Jiaxing[2];Huang, Yuying[3]

机构：[1]Shaoxing Univ, Coll Med Sci, Coll Chem & Chem Engn, Hangzhou 312000, Zhejiang, Peoples R China;[2]Chinese Acad Sci, Inst Plasma Phys, POB 1126, Hefei 230031, Peoples R China;[3]Chinese Acad Sci, Shanghai Inst Appl Phys, SSRF, Shanghai 201204, Peoples R China;[4]Dongguan Univ Technol, Sch Elect Engn, Guangzhou 523808, Guangdong, Peoples R China

年份：2016

卷号：148

起止页码：227

外文期刊名：CHEMOSPHERE

收录：SCI-EXPANDED(收录号：WOS:000371099700027)、、EI(收录号：20161102103431)、Scopus(收录号：2-s2.0-84960397044)、WOS

基金：Financial supports from the National Natural Science Foundation of China (21207092, 21577093), Natural Science Foundation of Zhejiang Province (LY15B070001) is acknowledged.

语种：英文

外文关键词：Nanoscale zero-valent iron Cr(VI); Layered double hydroxides; Synergistic effect; X-ray absorption fine structure (XAFS) spectra

外文摘要：Herein, the reduction of nanoscale zero-valent iron (NZVI) and adsorption of layered double hydroxides (LDH) to sequester Cr(VI) were well combined by the immobilization of NZVI onto LDH surface (NZVI/LDH). The characterization results revealed that LDH decreased NZVI aggregation and thus increased Cr(VI) sequestration. The batch results indicated that Cr(VI) sequestration by NZVI/LDH was higher than that of NZVI, and superior to the sum of reduction and adsorption. The LDH with good anion exchange property allowed the adsorption of Cr(VI), facilitating interfacial reaction by increasing the local concentration of Cr(VI) in the NZVI vicinity. X-ray absorption near edge structure (XANES) results indicated that Cr(VI) was almost completely reduced to Cr(III) by NZVI/LDH, but Cr(VI) was partly reduced to Cr(III) by NZVI with a trace of Cr(VI) adsorbed on corrosion products. The coordination environment of Cr from extended X-ray absorption fine structure (EXAFS) analysis revealed that LDH could be a good scavenger for the insoluble products produced during reaction. So, the insoluble products on NZVI could be reduced, and its reactivity could be maintained. These results demonstrated that NZVI/LDH exhibits multiple functionalities relevant to the remediation of Cr(VI)-contaminated sites. (C) 2016 Elsevier Ltd. All rights reserved.