文摘
CeO2-ZrO2 nanocages were prepared by Kirkendall effect, and their fluoride removal performance was investigated in batch studies. The obtained CeO2-ZrO2 adsorbent presented a good adsorption capacity in the pH range of 3.0-7.0, and the optimum pH range was 3.5-4.5. The adsorption isotherm could be better described by the Langmuir model than the Freundlich model. The Langmuir maximum capacity of the CeO2-ZrO2 adsorbent was calculated to be 175 mg/g at pH 4.0, which was much higher than that of other adsorbents reported previously. The effect of co-existing anions, such as sulfate, chloride, arsenate, and bicarbonate, on fluoride adsorption was systematically studied. Furthermore, the as-prepared adsorbent showed an excellent fluoride removal properties in real underground water. The adsorption mechanism was investigated by zeta potential measurement, Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS) analysis. Anion exchange and electrostatic interaction play key roles in fluoride removal.
