Solvothermal synthesis of nano‐CeO 2 aggregates and its application as a high‐efficient arsenic adsorbent

Aggregates of cerium dioxide nanoparticles (nano‐CeO 2 ) were successfully prepared via a facile solvothermal process in this study. The crystallographic information and morphological information of nano‐CeO 2 were systematically studied by X‐ray diffraction (XRD), transmission electron microscopy (TEM), laser particle size analyzer (LA) and specific surface area and pore size analyzer during the solvothermal process. Among all the obtained samples, the 18‐h solvothermal‐prepared nano‐CeO 2 aggregates show the best crystallinity and the largest specific surface area of 110.92 m 2 ·g −1 . Owing to the high activity derived from the high specific surface area of the aggregates, the application as arsenic (As) adsorption was also studied. The adsorption efficiency of arsenic by nano‐CeO 2 aggregates was established as the function of adsorbent dose, then pH value and at last adsorption time. The results indicate that the nano‐CeO 2 aggregates show a high efficiency in removing arsenic from low As concentration solution, from which the nano‐CeO 2 adsorbent could be easily separated. In addition, the adsorption kinetics is best fitted to pseudo‐second‐order model ( R 2 = 0.99999).