王鹏瑞^1,2， 杨 丹¹， 张 雪¹， 李 静¹， 闫良国¹

（1. 济南大学 水利与环境学院， 山东 济南 250022；2. 济南市市中区环境监测站， 山东 济南 250001）

DOI:10.13732/j.issn.1008-5548.2021.03.008

收稿日期： 2020-12-27，修回日期：2021-02-22，在线出版时间：2021-04-07 11:27。

基金项目：国家自然科学基金项目，编号：21577048。

第一作者简介：王鹏瑞(1990—)，男，硕士研究生，研究方向为环境监测与水污染治理技术。E-mail：502276827@qq.com。

通信作者简介：闫良国(1971—)，男，博士，教授，博士生导师，研究方向为环境功能材料。E-mail：chm_yanlg@ujn.edu.cn。

摘要：为寻找高效吸附水中六价铬(Cr(Ⅵ))的水滑石功能材料，以水热法制备钙铝(CaAl-LDH)和铁铝水滑石(FeAlLDH) 2种吸附剂，通过X射线衍射仪、红外光谱仪、扫描电镜和比表面积测定仪研究其结构和性质，采用批次平衡实验比较研究其对水中Cr(Ⅵ)的吸附性能。结果表明:CaAl-LDH和FeAl-LDH具有水滑石的特征衍射峰和介孔结构，呈六边形片状，比表面积分别为8.746、159.5 m²/g; 2种材料对Cr(Ⅵ)的吸附速率较快，在30 min达到平衡，且吸附过程不受溶液pH值的影响，溶液中存在的常见阴离子对Cr(Ⅵ)影响较小;吸附动力学和等温线数据分别符合拟二级动力学方程和Langmuir等温线模型，CaAl-LDH和FeAl-LDH对Cr(Ⅵ)的最大吸附量分别为34.92、51.31 g/kg。

关键词：钙铝水滑石；铁铝水滑石；六价铬；吸附；水热法

Abstract：To obtain layered double hydroxide( LDH) based functional materials for efficient removal hexavalent chromium( Cr( Ⅵ)) from water,CaAl-LDH and FeAl-LDH were prepared by the hydrothermal method. The structure and property were investigated by X-ray diffraction pattern( XRD),Fourier transform infrared spectroscopy,scanning electron microscopy and specific surface area measurement. Batch equilibrium experiments were used to evaluate the adsorption performance of the as-prepared CaAl-LDH and FeAl-LDH for aqueous Cr( Ⅵ). The experimental results show that CaAl-LDH and FeAl-LDH have typical XRD peaks of LDH,mesoporous structure and hexagonal laminar shape. The specific surface areas are 8. 746 and 159. 5 m²/g. The adsorption processes of Cr( Ⅵ) by CaAl-LDH and FeAl-LDH are fast and reache equilibrium within 30 min,andare not affected by the initial solution pH value and the common coexisting anions. The kinetic and isothermal data follow the pseudo-second-order kinetic equation and the Langmuir model,respectively. The maximum adsorption capacities of CaAl-LDH and FeAl-LDH for aqueous Cr( Ⅵ) are 34. 92 and 51. 31 g/kg.

Keywords：CaAl-LDH; FeAl-LDH; hexavalent chromium; adsorption; hydrothermal method

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