Abstract:

Iron oxyhydroxide (FeOOH) has good performance for adsorptionof heavy metal ions because of its high surface charge and large surface area. Three different methods were used to synthesize FeOOH. The identities of FeOOH were verified by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The surface area of the  nanoparticle was measured by a surface area analyzer, and thezeta potential of the  nanoparticle was obtained by a zeta potential analyzer. The XRD peaks of these three crystallites well matched with the standard β-FeOOH. TheTEM images showed that they  were nanoscaled, and the morphologies were rectangle, shuttle and spindle, respectively. The three kinds of β-FeOOH wereusedto conduct adsorption experiments to investigate their adsorption capacity of Cr (Ⅵ) in the simulated water. The result of the adsorption experiments showed that β-FeOOH which synthesized with organic macromolecules had high removal efficiency for Cr (Ⅵ) in comparison with other samples. Adsorption isotherm studies indicated that the adsorption capacities of β-FeOOH were 15.45 mg／g, 16.87 mg／gand18.48mg／g at 293K, 303K and 313K, respectively. An increase in the valuesof K_F　with the increasing temperature indicated that the adsorption was an endothermic process.

Key words: nano β-FeOOH; synthesis; Cr (Ⅵ); adsorption