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以钠基膨润土为原料、壳聚糖为插层材料,制备了壳聚糖插层膨润土(CS-Bent),用于去除废水中的U(Ⅵ).考察了pH、吸附剂投加量、U(Ⅵ)初始含量和吸附时间对CS-Bent吸附U(Ⅵ)的影响.结果表明,当温度为25℃,pH为6,CS-Bent投加量为1.6 g/L时,吸附平衡时间为60 min,对U(Ⅵ)的最大吸附量可达59.52 mg/g.Langmuir等温吸附模型和准2级动力学模型均可较好地拟合其吸附过程.X-射线衍射分析表明壳聚糖已经成功插入膨润土层间,傅里叶变换红外光谱、扫描电镜分析表明CS-Bent成功吸附U(Ⅵ).以0.1 mol/L的HC1溶液作为解吸液,经过5次解吸后去除率仍有90％以上,表明CS-Bent可再生,具有较好的重复利用性.“,”Abstra ct:A chitosan intercalated bentonite was prepared with Na-bentonite as raw material and chitosan as intercalation agent.The synthesized CS-Bent composites were applied to adsorb U(Ⅵ) from aqueous solutions.The effects ofpH,adsorbent dosage,initial U(Ⅵ)ions content,temperature and adsorption time on adsorption of U(Ⅵ) was investigated by static adsorption experiments.The results show that the maximum adsorption capacity for U(Ⅵ) ions is 59.52 mg/L occurs at 25 ℃when the pH=6 and adsorbent dosage of 1.6 g/L while the adsorption reaches equilibrium within 60 min.The adsorption proces s fits well with the Langmuir isotherm model and pseudo-second-order kinetic model.The X-ray diffraction indicated chitosan has already intercalated bentonite,Fourier transformed infrared spectroscopy and scanning electron microscopy indicates that it had absorb U(Ⅵ) successfully.The used CS-Bent can be desorbed by 0.1 mol/L HCl (the fifth desorption rate is up to 90％),which indicates CS-Bent can be reusable.