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.
作者
邹志强
黄李金鸿
李新冬
肖文刚
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)
出处
《矿冶工程》
CAS
北大核心
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)。
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
ion⁃adsorbed REE deposit
rare earth
in⁃situ leaching
lanthanum ions
ammonium ions
kaolinite
adsorption
density functional theory
