Enhanced fluoride removal from aqueous solution by mixed oxides derived from Mg/Al/Fe hydrotalcite
Mg/Al/Fe复合氧化物吸附去除水体中氟化物的研究

In this study, Mg/Al/Fe hydrotalcites (MAF) with different iron content were prepared by hydrothermal method. Based on the characterization of XRD, there existed a suitable iron ratio and the layer structure would be destroyed with excessive iron. The morphology and property of the mixed oxides derived from MAF (CMAF) were characterized by SEM and BET. The adsorption of fluoride on CMAF was also investigated. In comparison with CMA (iron content was 0), CMAF exhibited a higher efficiency toward fluoride removal (the maximum adsorption capacity is 75.2 mg/g). Langmuir isotherm was found more suitable to describe the adsorption process. Moreover, the structure of CMAF shifted to layer structure after fluoride adsorption. The result indicates that fluoride has intercalated the layer structure of hydrotalcite, leading to higher efficiency of fluoride removal.