Ultra-rapid fluoride removal by magnetic calcium-doped layered yttrium hydroxides at environmental-relevant concentrations

• Published in: Chemical engineering science Vol. 280; p. 119035
• Main Authors: Liang, Ying, Chen, Fengjie, Yu, Ting, Yan, Yubo, Zhou, Zhen, Liang, Yong, Wang, Yawei
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 05.10.2023
• Subjects: Adsorption; Fluoride contamination; Ion exchange interactions and Electrostatic; Magnetic γ-Fe2O3/Ca-Y LRHs; Ultra-rapid and efficient removal; Ion exchange interactions and Electrostatic; Magnetic γ-Fe2O3/Ca-Y LRHs; Ultra-rapid and efficient removal; Adsorption; Fluoride contamination
• ISSN: 0009-2509; 1873-4405
• DOI: 10.1016/j.ces.2023.119035

•Magnetic γ-Fe2O3/Ca-Y LRHs were successfully synthesized.•Electrostatic and ion exchange interactions are involved in the F- removal process.•OH–, H2O and Cl- in interlayer spaces were the main ligands to be replaced by F-.•γ-Fe2O3/4Ca-Y LRHs has ability to remove F- in a real aquatic environment. Currently, there is still a lack of strategies for rapid removal of fluoride at environmental-relevant concentrations. In this study, in which several magnetic calcium doped layered yttrium hydroxides (γ-Fe2O3/Ca-Y LRHs) modified with γ-Fe2O3 were synthesized and used for fluoride removal. The magnetic and adsorption properties analysis indicated γ-Fe2O3/4Ca-Y LRHs demonstrated performance of magnetism and adsorption ability. According to the pseudo-second-order and Langmuir models, the equilibrium time and maximum monolayer adsorption capacity of γ-Fe2O3/4Ca-Y LRHs was 2 min and 43.98 ± 2.34 mg/g, respectively. The adsorption and desorption studies revealed electrostatic and ion exchange interactions are involved in the defluorination mechanism, and chloride and oxygenated groups in interlayer spaces were the main ligands for fluoride exchanged. The potential applications on surface water demonstrate that the ability of γ-Fe2O3/4Ca-Y LRHs to remove fluoride at environmental-relevant concentrations. These findings are expected to facilitate the process of rapid removal of fluoride contamination in the aqueous environment.