采用静态批式法研究了不同 pH 值、Cs+浓度及固液比对膨润土吸附 Cs+的影响，同时，利用傅里叶红外光谱（FTIR）、扫描电镜（SEM）、X 射线能谱（EDS）和 X 射线衍射仪（XRD）分析了膨润土对 Cs+的吸附过程。研究结果表明：Cs+初始浓度在100～500 mg／L 变化时，膨润土对 Cs+的吸附效率由94．17％下降至47．09％，吸附量却从8．71 mg／g 上升至21．79 mg／g；膨润土对 Cs+的吸附效率与固液比存在正相关，当固液比在0．005～0．1变化时，膨润土对 Cs+的吸附效率由39．96％增加至97．22％，而吸附量由23．48 mg／g 降至2．86 mg／g；pH 值增大时膨润土对 Cs+的吸附性能加强，除了在 pH 值为7的时候略有下降，且吸附前溶液无论为酸性、中性还是碱性，吸附后溶液都呈中性。FTIR、SEM-EDS 和 XRD 分析结果表明，膨润土吸附Cs+的过程主要表现为离子交换反应和表面配位反应。%The adsorption of bentonite for Cs+ was studied by batch technique under ambient conditions.The different concentra-tions of Cs+ ,solid-to-liquid ratio and pH value on the sorption to bentonite was examined.The adsorption characteristics of Cs+by Bentonite were analyzed by FTIR,SEM,EDX and XRD.The results show that the adsorption percentage of bentonite to Cae-sium decreases from 94.17% to 47.09%,but the adsorptive capacity increases from 8.71 mg/g to 21.79 mg/g when the initial Cs+ concentration increases from 100 mg/L to 500 mg/L.The adsorptive capacity decreases from 23.48 mg/g to 2.86 mg/g and the adsorption percentage increases from 39.96% to 97.22% with the increasing of solid-to-liquid ratio from 0.005 to 0.1.The adsorptive capacity and adsorption percentage increase with the increasing of the pH value except for a little decrease at pH=7. By comparing the pH value before and after the adsorption of bentonite for cesium ion,the result shows that the pH value is neu-tral after the adsorption no matter the solution is acidic,neutral or alkaline before the adsorption of bentonite for Cs+ .Therefore, bentonite as backfill material can reduce the corrosion of packaging container of metal by the acid and alkali.The results on FTIR, SEM,EDX and XRD show that the adsoprtion mechanism of Cs+ with bentonite mainly can be ion exchange and surface combination.
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