Effect of calcination temperature on Mg-Al bimetallic oxides as sorbents for the removal of F~- in aqueous solutions

摘要

Bimetallic oxides were synthesized from hydrotalcite using increasing calcination temperatures (873, 1073,1273 K). These bimetallic oxides were fully characterized and the sorption density of F~- was investigated. X-ray diffraction patterns for the produced bimetallic oxides showed that MgO was the primary phase within the range of investigated calcination temperatures, but MgO crystallinity increased with calcination temperature and an additional MgAl_2O_4 phase was formed. In the process of F sorption, the bimetallic oxides were primarily transformed into hydrotalcite with intercalation of F~- The Higher calcination temperature increased the MgAl_2O_4 phase, which did not contribute to the immobilization of F~-. These findings show that optimizing the calcination temperature can be used to maximize the sorption density of this material for F~ removal.