摘要
用批量平衡法研究了pH值、离子强度、反应时间和温度对Cd(Ⅱ)在伊利石上吸附的影响。并用Lagrange准二级动力学方程、Langmuir等温线方程、Freundlich等温线方程以及D-R等温线方程对实验数据进行拟合。结果表明:pH值和离子强度对Cd(Ⅱ)在伊利石上的吸附均有明显的影响,低pH值下Cd(Ⅱ)在伊利石上的吸附主要是通过外层络合和离子交换;而在高pH值下Cd(Ⅱ)的吸附主要是通过内层络合作用进行;Cd(Ⅱ)在伊利石上的吸附动力学符合Lagrange准二级动力学方程;热力学符合Langmuir等温线方程;升高温度有利于Cd(Ⅱ)在伊利石上的吸附。
The sorption of Cd( Ⅱ) on illite was studied as a function of pH, ionic strength, time and temperature under ambient conditions using batch technique. The results indicate that sorption of Cd( Ⅱ ) on illite is strongly dependent on pH values and ionic strength. At low pH, the sorption is dominated by outer-sphere surface complexation and ion exchange on illite surfaces, whereas inner-sphere surface complexation is the main sorption mechanism at high pH. The adsorption of Cd(Ⅱ ) on illite is found to follow pseudo-second-order kinetic model well. Sorption of Cd( Ⅱ ) increase with increasing temperature and fit the Langmuir isotherm well.
出处
《核化学与放射化学》
CAS
CSCD
北大核心
2012年第6期358-363,共6页
Journal of Nuclear and Radiochemistry
基金
国家自然科学基金资助项目(20967006
21107115)