Du Jing, Zhao Yanyan, Huang Tao, Li Hui, He Jia
School of Materials Engineering, Changshu Institute of Technology, Suzhou 215500, China.
Changsha Institute of Mining Research Co., Ltd., Changsha 410012, China.
Materials (Basel). 2025 Jun 5;18(11):2665. doi: 10.3390/ma18112665.
Excessive intake of fluorine (F) over time can lead to acute or chronic fluorosis. In this study, a novel Fe-Ce-based layered hydroxide composite (DD-LHC) was synthesized and applied in both batch and column modes to develop new adsorbent materials and to obtain efficient removal of fluorine (F) anions from wastewater. DD-LHC achieved better adsorption results and material stability compared to green rusts (GR, Fe-Fe hydroxide). The maximum adsorption capacity of DD-LHC for F was 44.68 mmol·g, obtained at an initial pH of 5 and initial concentration of 80 mM. The substitution of Ce for Fe in the intercalated layered structure of GR potentially changed the reaction pathways for F removal, which are typically dominant in the layered double hydroxides (LDHs) of Fe-Fe. The molecular structure of layered hydroxides combined with the three-dimensional (3D) metal frame of Fe-O-Ce was integrated into DD-LHC, resulting in nanoscale particle morphologies distinct from those of GR. The pseudo-first-order kinetic model effectively described the whole adsorption process of DD-LHC for F. DD-LHC exhibited notable selectivity for F across a wide pH range. The removal process of F by DD-LHC was dominated by Ce-F coordination bonds, with additional influences from auxiliary pathways to different extents.
长期过量摄入氟（F）会导致急性或慢性氟中毒。在本研究中，合成了一种新型的铁铈基层状氢氧化物复合材料（DD-LHC），并以批次和柱模式应用，以开发新型吸附材料并从废水中有效去除氟（F）阴离子。与绿锈（GR，铁 - 铁氢氧化物）相比，DD-LHC取得了更好的吸附效果和材料稳定性。DD-LHC对F的最大吸附容量为44.68 mmol·g，在初始pH为5和初始浓度为80 mM时获得。在GR的插层层状结构中用Ce取代Fe可能改变了F去除的反应途径，这在铁 - 铁层状双氢氧化物（LDH）中通常占主导地位。层状氢氧化物的分子结构与Fe-O-Ce的三维（3D）金属框架相结合，整合到DD-LHC中，产生了与GR不同的纳米级颗粒形态。伪一级动力学模型有效地描述了DD-LHC对F的整个吸附过程。DD-LHC在很宽的pH范围内对F表现出显著的选择性。DD-LHC对F的去除过程以Ce-F配位键为主，不同程度地受到辅助途径的额外影响。
