物理化学学报2021，Vol.37Issue(10)：104-112,9.DOI:10.3866/PKU.WHXB201911009
由单层薄水铝石制备的活性氧化铝处理水中氟离子
Defluoridation of Water Using Active Alumina Derived from Single-Layer Boehmite
摘要
Abstract
The preparation of high-efficiency and low-cost adsorbents for the defluoridation of drinking water remains a huge challenge.In this study,single-layer and multi-layer boehmite were first synthesized via an organic-free method,and active alumina used for fluoride removal from water was obtained from the boehmite.The advantage of a single layer is that more aluminum is exposed to the surface,which can provide more adsorption sites for fluoride.The active alumina adsorbent derived from single-layer boehmite exhibits a high specific surface area and excellent adsorption capacity.The high surface area ensures a high adsorption capacity,and the organic-free synthesis method lowers the preparation cost.The as-prepared adsorbent was characterized by X-ray powder diffraction (XRD),scanning electron microscopy (SEM),high-resolution transmission electron microscopy (HRTEM),Fourier-transform infrared spectroscopy (FTIR) and nitrogen adsorption-desorption analysis.The single-layer structure of boehmite was determined from the simulated XRD diffraction pattern of single-layer boehmite.The disappearance of the (020) diffraction peak of boehmite illustrates that the dimensions in the b direction are extremely small,and according to the XRD simulation results,the single-layer structure of boehmite could be determined.Single-layer boehmite with a surface area of 789.4 m2·g-1 was formed first.The active alumina obtained from the boehmite had a surface area of 678.4 m2·g-1,and the pore volume was 3.20 cm3·g-1.The fluoride adsorption of the active alumina was systematically studied as a function of the adsorbent dosage,contact time,concentration,co-existing anions,and pH.The fluoride adsorption capacity of the active alumina obtained from the single-layer boehmite reached up to 67.6 mg·g-1,which is higher than those of most alumina adsorbents reported in the literature.The adsorption capacities of the active alumina are related to the specific surface area and the number of hydroxyl groups on the surface.Dosages of 0.6,1.0,and 2.6 g·L-1 of active alumina were able to lower the 10,20,and 50 mg·L-1 fluoride solutions,respectively,below the maximum permissible limit of fluoride in drinking water in China (1.0 mg·L-1),suggesting that the active alumina synthesized in this work is a promising adsorbent for defluoridation of drinking water.In addition,the fluoride adsorption is applicable in a wide pH range from 4 to 9 and is mainly interfered by SO42-and PO43-.Further investigation suggested that the fluoride adsorption of the active alumina follows the pseudo second-order model and Langmuir isotherm model.关键词
除氟/活性氧化铝/单层/大比表面积/吸附/高吸附量/无有机物Key words
Defluoridation/Active alumina/Single layer/High surface area/Adsorption/High adsorption capacity/Organic-free分类
化学化工引用本文复制引用
孙建川,宋家庆,王旭辉,陈帅奇,廖艳清,郜阿旺,胡雨昊,杨涛,徐向宇,王颖霞..由单层薄水铝石制备的活性氧化铝处理水中氟离子[J].物理化学学报,2021,37(10):104-112,9.基金项目
The project was supported by the Shanghai Key Laboratory of Green Chemistry and Chemical Processes,East China Normal University,China (H2016107).华东师范大学上海绿色化学与化学过程重点实验室(H2016107)资助项目 （H2016107）
