摘要
通过傅立叶变换红外光谱(FTIR)、X射线衍射(XRD)、扫描电子显微镜(SEM)等测试手段对膨润土的物相组成、微观形貌特征等进行了表征。采用静态批式法研究了膨润土对溶液中63 Ni(Ⅱ)的去除效果,考察了吸附时间、pH以及共存阳离子等因素对其吸附性能的影响。膨润土对63 Ni(Ⅱ)吸附符合拟二级动力学方程且受到pH和离子强度影响较大。在低pH时,离子交换和外层络合是主要机理;随着pH增大发生去质子化反应,内层络合或者表面沉淀是主要机理。此外,共存电解质阳离子及腐植酸均对吸附影响显著。
In this work, the bentonite was characterized by Fourier transform infrared （FTIR） spectroscopy, X-ray powder diffraction（XRD）, scanning electron microscope （SEM）. The sorption of radionuclide 6aNi（ Ⅱ ） on bentonite was investigated by batch tech- nique under ambient conditions. The effect of contact time, pH and coexistent electrolyte cations on 63Ni（ Ⅱ ） sorption to bentonite was examined. The results demonstrate that the kinetic adsorption data is well described by the pseudo-second-order model and the sorption of 63Ni（ Ⅱ ） is strongly dependent on pH and ionic strength at low pH values. The sorption of 63 Ni（ Ⅱ ） is dominated by outer-sphere surface complexation or ion exchange at low pH, whereas inner-sphere surface complexation is the main sorption mechanism at high pH. In addition, the removal of 6aNi（ Ⅱ ） to bentonite is also strongly affected by FA and cations.
出处
《核化学与放射化学》
CAS
CSCD
北大核心
2012年第6期352-357,共6页
Journal of Nuclear and Radiochemistry
基金
国家自然科学基金资助项目(20971033
21107115)
