文献类型：期刊文献

英文题名：Mechanism insights into enhanced Cr(VI) removal using nanoscale zerovalent iron supported on the pillared bentonite by macroscopic and spectroscopic studies

作者：Li, Yimin[1];Li, Jianfa[1];Zhang, Yuling[1]

机构：[1]Shaoxing Univ, Coll Chem & Chem Engn, Shaoxing 312000, Zhejiang, Peoples R China

年份：2012

卷号：227

起止页码：211

外文期刊名：JOURNAL OF HAZARDOUS MATERIALS

收录：SCI-EXPANDED(收录号：WOS:000306627000027)、、EI(收录号：20122615180207)、Scopus(收录号：2-s2.0-84862664829)、WOS

基金：This work was supported by the National Natural Science Foundation of China (20977063, 21177088). The authors acknowledge Dr. Guodong Sheng (Institute of Plasma Physics, Chinese Academy of Science) for the XAFS determination and analysis. The authors also gratefully acknowledge Prof. Yuying Huang and Dr. Xing Gao (SSRF, China) for helpful technical assistance on XAFS experiments.

语种：英文

外文关键词：Pillared bentonite; Nanoscale zerovalent iron; Removal; Hexavalent chromium; X-ray absorption fine structure (XAFS)

外文摘要：NZVI was supported on a pillared bentonite (Al-bent) to enhance the reactivity of NZV1 and prevent its aggregation. The performance and mechanisms of the combined NZVI/Al-bent on removing hexavalent chromium (Cr(VI)) was investigated by batch and XAFS experiments. The batch investigations indicated that Cr(VI) could be almost completely removed by NZVI/Al-bent after 120 min. The efficiency was not only much higher than that by NZVI (63.0%), but also superior to the sum of NZVI reduction and Al-bent adsorption (12.4%). Besides, NZVI/Al-bent exhibited good stability and reusability, and Al-bent could reduce the amount of iron ions released into the solution. XANES results provided evidence that NZVI/Al-bent could reduce Cr(VI) entirely into Cr(III), while NZV1 reduced Cr(VI) partly into Cr(III) with a trace of Cr(VI) adsorbed on the corrosion products. The structure of Cr(VI)-treated NZVI/Al-bent determined with EXAFS revealed the formation of Cr-Al/Si bond, suggesting that some insoluble Cr(III) species might be transferred to the surface of Al-bent, therefore the precipitates on iron surface could be greatly reduced. The results demonstrated that Al-bent plays a significant role in enhanced reactivity and stability of NZVI, and may shed new light on design and fabrication of supported NZVI for environmental remediation. (C) 2012 Elsevier B.V. All rights reserved.