Characterization and preparation of a novel silicon-zirconium composite by a co-precipitation approach

A novel silicon-zirconium (Si-Zr) composite adsorbent was prepared via co-precipitation approach. The surface morphology and chemical structure of the prepared Si-Zr composites were characterized by SEM, FTIR and XRD. The influence of synthesis conditions on the performance of defluorination was observed and evaluated. The results show that with 600℃ of calcination temperature, the Si-Zr composites exhibits blooming porous structure and large specific surface, which benefits the absorption of aqueous fluoride. Zirconium and silicon in the material are combined as Si—O—Zr composite oxides. Additionally, the prepared composites can bond stably with fluoride anion and are resistive in desorption. The comprehensive experiments reveal that calcination temperature and time, ratio of raw material (ZrOCl₂∶Na₂SiO₃) dominate the application performance of the Si-Zr composites.