镧离子和铵离子在高岭石表面的吸附机理研究  

Adsorption Mechanism of Lanthanum and Ammonium Ions on Kaolinite

作　　者：邹志强[1,2] 黄李金鸿 李新冬 肖文刚[2] 钱艳涛 黄万抚 ZOU Zhiqiang;HUANG Lijinhong;LI Xindong;XIAO Wengang;QIAN Yantao;HUANG Wanfu(School of Resources and Environmental Engineering,Jiangxi University of Science and Technology,Ganzhou 341000,Jiangxi,China;Ganzhou Rare Earth Mining Co Ltd,Ganzhou 341000,Jiangxi,China;School of Architecture and Design,Jiangxi University of Science and Technology,Ganzhou 341000,Jiangxi,China;School of Civil and Surveying&Mapping Engineering,Jiangxi University of Science and Technology,Ganzhou 341000,Jiangxi,China)

机构地区：[1]江西理工大学资源与环境工程学院,江西赣州341000 [2]赣州稀土矿业有限公司,江西赣州341000 [3]江西理工大学建筑与设计学院,江西赣州341000 [4]江西理工大学土木与测绘工程学院,江西赣州341000

出　　处：《矿冶工程》2023年第4期52-56,60,共6页Mining and Metallurgical Engineering

基　　金：国家自然科学基金(41662004);赣州市“苏区之光”人才支持项目;赣南离子型稀土资源基地典型固废循环利用集成示范项目(2020YFCL1909100)。

摘　　要：基于密度泛函理论的平面波赝势第一性原理计算,研究了La^(3+)和NH_(4)^(+)在高岭石(001)面和(00⁃1)面的吸附机理。结果表明,La^(3+)主要通过静电作用吸附在高岭石表面,NH_(4)^(+)除静电作用外,还存在氢键作用,比La^(3+)有更多的电子转移到高岭石表面上。离子在高岭石(001)面的吸附能绝对值从大到小排序为:La^(3+)>NH_(4)^(+)>H_(2)O;离子在高岭石(00⁃1)面的吸附能绝对值从大到小排序为:NH_(4)^(+)>La^(3+)>H_(2)O。La^(3+)更容易吸附在(001)面上,而NH_(4)^(+)更容易吸附在(00⁃1)面上。采用硫酸铵作浸出剂时,浸出剂浓度需要提高到一定值才能使吸附在高岭石(001)面上的La^(3+)等稀土离子被有效地交换下来。The adsorption mechanism of La^(3+)and NH_(4)^(+)ions on(001)and(00⁃1)planes of kaolinite has been studied based on the first⁃principle calculation of plane⁃wave pseudopotentials of density functional theory.The results show that La^(3+)ions are mainly adsorbed on kaolinite surface through electrostatic interaction,while NH_(4)^(+)ions are adsorbed thereon through both electrostatic interaction and hydrogen bonding,with more electrons transferred onto kaolinite surface than La^(3+).The absolute values of adsorption energy for ions on(001)plane of kaolinite are in the following descending order:La^(3+)>NH_(4)^(+)>H_(2)O,while on(00⁃1)plane in the following descending order:NH_(4)^(+)>La 3+>H_(2)O.It is found that La^(3+)ions are prone to be adsorbed on(001)plane,while NH_(4)^(+)ions are prone to be adsorbed on(00⁃1)plane.When ammonium sulfate is used as a leaching agent,rare earth ions like La^(3+)adsorbed on the(001)plane can only be effectively displaced with the leaching agent at a certain concentration.

关 键 词：离子型稀土矿 稀土 原地浸矿 镧离子 铵离子 高岭石 吸附 密度泛函理论 

分 类 号：O641[理学—物理化学]