Behavior and mechanism of Cd(II) adsorption on loess-modified clay liner
Behavior and mechanism of Cd(II) adsorption on loess-modified clay liner
复制标题
DOI：
10.1080/19443994.2012.669153
复制
发表时间：
2012-02
影响因子：
1.1
通讯作者：
Qinglei Yang;Jinli Zhang;Qing Yang;Yong-qiang Yu;Gang Yang
中科院分区：
文献类型：
--
作者：
Qinglei Yang;Jinli Zhang;Qing Yang;Yong-qiang Yu;Gang Yang
摘要镉是一种常见于垃圾渗滤液中的有毒重金属，已引起严重的公共卫生问题。因此，有必要寻找一种经济有效的方法来处理含镉垃圾渗滤液。黄土改性粘土被证明是有效的去除镉（II）的垃圾渗滤液。黄土改性粘土对Cd（II）的吸附容量为7.08mg/g。影响吸附Cd（II）的因素包括黄土比例、泥浆浓度、初始溶液pH、温度和作用时间。吸附等温线和动力学数据分别符合Langmuir模型和准二级动力学模型。热力学行为表明，吸附过程是自发的吸热过程，随着时间的延长，体系无序度增加。Cd（II）在黄土改性粘土上的吸附过程包括与粘土矿物的化学反应和表面络合作用。化学沉淀被认为是主要的方法。
Abstract Cadmium is a toxic heavy metal which is common in landfill leachate and it has caused serious public health problems. It is necessary to find a cost effective method to deal with landfill leachate containing Cd(II). The loess-modified clay is proved to be effective to remove Cd(II) removal from landfill leachate. The adsorption capacity of loess-modified clay towards Cd(II) has been determined to be about 7.08 mg/g. Factors affecting the adsorption of Cd(II) include loess proportion, slurry concentration, initial solution pH, temperature and event duration. The adsorption isotherms and kinetic data are well fit with the Langmuir model and pseudo-second order kinetics model, respectively. The thermodynamic behavior reveals that the adsorption process is spontaneous and endothermic and the system disorder increases with time. The adsorption of Cd(II) on loess-modified clay involves chemical reaction and surface complexation with clay minerals. Chemical precipitation is considered as the dominant me...