One-step synthesis of mesoporous two-line ferrihydrite for effective elimination of arsenic contaminants from natural water

摘要

Mesoporous two-line (2-lines) ferrihydrite is successfully synthesized by a facile one-step method. The ferrihydrite is characterized by X-ray diffraction (XRD), Raman spectrum, N2 adsorption, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The 2-lines ferrihydrite with mesoporous structure possesses excellent adsorption performance for arsenic (As(iii)) contamination. Experimental results show that As(iii) contamination can be effectively removed within 2 h by this 2-lines ferrihydrite, which is attributed to the special mesoporous structure and large surface area (133 m2 g-1). The As(iii) loading capacity of our obtained mesoporous 2-lines ferrihydrite is up to 128 mg(As) g-1(Fe). In addition, As(iii) can be easily desorbed from 2-lines ferrihydrite by simple heat treatment in alkali solution. After reusage for 10 times, it still presents good adsorption performance, indicating the excellent stability of the 2-lines ferrihydrite. Furthermore, the mesoporous 2-lines ferrihydrite is also effective for As(iii) removal when some natural water constituents are present. Therefore, the high adsorption capability of the mesoporous 2-lines ferrihydrite makes it a potentially attractive adsorbent for the removal of As(iii) contamination from natural water.