Abstract：Adsorption of heavy metal ions such as Cr⁶⁺on vermiculite, montmorillonite and bentonite was studied.With the static experimental method, the adsorption factors, rules, optimum adsorption condition and adsorption properties of the three kinds of clay minerals were obtained. The active group structure, morphology and chemical elements were examined by fourier transform infrared spectroscopy, scanning electron microscope, energy dispersive spectrometer and X-ray diffraction.The results indicate that the adsorption equilibriums are achieved in 60 minutes. The uptake of Cr⁶⁺ by the three kinds of clay minerals maintaines high efficiencies in the p H of 5. The adsorption of Cr⁶⁺ onto vermiculite, montmorillonite and bentonite could be well described by pseudo-second-order model. The theoretical maximum adsorption amount fitted by Langmuir isothermal are 19.959, 8.3963, 15.432 mg·g^-1. As the results of optimization test show, optimal condition for adsorption of Cr⁶⁺ on vermiculite, montmorillonite and bentonite are adsorbent concentration 1.0 g·L^-1, adsorbate concentration 300 mg·L^-1, p H5.0, reaction temperature 25 ℃, adsorption time 120 min. Among the three, vermiculite has the best adsorption effect on Cr⁶⁺.

Keywords: vermiculite; montmorillonite; bentonite; adsorption

通信作者简介：

朱健（1983—），男，博士，讲师，研究方向为土水重金属污染控制与修复。E-mail:zhujian198312@163.com；

王平（1964—），男，博士，教授，博士生导师，研究方向为土水污染控制与生物修复。E-mail: csfuwp@163.com。