Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, 219 Ningliu Road, Nanjing 210044, China.
Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, 219 Ningliu Road, Nanjing 210044, China.
J Hazard Mater. 2020 Apr 15;388:121734. doi: 10.1016/j.jhazmat.2019.121734. Epub 2019 Nov 21.
Three core/shell/shell MgAl-LDH composites using FeO microspheres as the core, a SiO matrix as the inner layer and a MgAl-LDH layer as the outer shell have been synthesized for the removal and recovery of phosphate and fluoride from water by a magnetic separation technique. The synthetic mesoporous MgAl-LDH composites show good magnetic separability, well-defined pore distributions, and have specific surface areas of 73 m g, 168 m g, and 137 m g for FeO@SiO@LDH350, FeO@SiO@mLDH350, and FeO@mSiO@mLDH350, respectively. The adsorption isotherms of both phosphate and fluoride on these MgAl-LDH composites can be well fitted with the Langmuir model. The maximum adsorption capacities of 57.07 mg g and 28.51 mg g were obtained on FeO@mSiO@mLDH350 for phosphate and fluoride, respectively, much higher than those of other LDH-type materials. The adsorbed phosphate and fluoride could be successfully recovered by NaNO-NaOH solution, and the regenerated MgAl-LDH composites could be reused for phosphate and fluoride removal. Owing to their high adsorption capacities of both phosphate and fluoride, easy magnetic separation from solution, and good reusability, the mesoporous MgAl-LDH composites are expected to have potential applications in removal or recovery of fluoride or phosphate from water.
采用 FeO 微球作为核、SiO2 作为内层、MgAl-LDH 作为外壳，制备了三种核壳壳型 MgAl-LDH 复合材料，用于水体系中磷酸盐和氟化物的去除和回收。合成的介孔 MgAl-LDH 复合材料具有良好的磁分离性能、明确的孔分布和分别为 73、168 和 137 m²/g 的比表面积，对于 FeO@SiO@LDH350、FeO@SiO@mLDH350 和 FeO@mSiO@mLDH350。磷酸盐和氟化物在这些 MgAl-LDH 复合材料上的吸附等温线均能很好地符合 Langmuir 模型。在 FeO@mSiO@mLDH350 上，对磷酸盐和氟化物的最大吸附容量分别为 57.07 和 28.51 mg/g，远高于其他 LDH 型材料。吸附的磷酸盐和氟化物可以用 NaNO-NaOH 溶液成功回收，再生的 MgAl-LDH 复合材料可以重复用于去除磷酸盐和氟化物。由于其对磷酸盐和氟化物具有较高的吸附容量、易于从溶液中磁分离以及良好的可重复使用性，介孔 MgAl-LDH 复合材料有望在水中去除或回收氟化物或磷酸盐方面具有潜在应用。
