writer：Facui Yang, Shiqi Sun, Xiaoqi Chena, Yue Chang, Fei Zha, Ziqiang Lei
keywords：Palygorskite，Mg–Al layered double hydroxides， Adsorption， Heavy metal ions
source：期刊
Issue time：2016年

Highly effective clay adsorbents ofMg–Al layered double hydroxidesmodified palygorskite were prepared from the mixture of metal salts, urea and palygorskite by the in situ hydrothermal crystallization method. The obtained adsorbents were characterized by FT-IR, TG, XRD and SEM/EDS. The adsorption performances were evaluated for the removal of Pb2+, Cu2+ and Ni2+  in the aqueous solution. The adsorption capacities of the three metal cations at variable pH, contact times andmetal concentrations were determined by atomic adsorption spectrometry. The adsorption capacities of the three metal cations on Mg–Al layered double hydroxides modified palygorskite were higher than those of palygorskite and Mg–Al layered double hydroxides at the initial metal ion concentration of 100 mg/L and initial pH of 5.0. The experimental data showed a good compliance with the Langmuir isotherm and the pseudo-second-order kinetic model. Taking advantage of the combined benefits of palygorskite and Mg– Al layered double hydroxides, the as-prepared adsorbents exhibit selective and fast rating adsorption for Pb2+.