离子型稀土柱浸过程铵与稀土的分布及传质行为研究  

Distribution and Mass Transfer Behavior of Ammonium and Rare Earth During Column Leaching of Ionic Rare Earth

作　　者：肖信锦 黄金 王慧娟 邓扬悟 王林生[1] Xiao Xinjin;Huang Jin;Wang Huijuan;Deng Yangwu;Wang Linsheng(National Engineering Research Center for lonic Rare Earth/Jiangxi lonic Rare Earth Engineering Research Co.,Ltd.,Ganzhou 341000,China;School of Resources and Environmental Engineering,Jiangxi University of Science and Technology,Ganzhou 341000,China)

机构地区：[1]国家离子型稀土资源高效开发利用工程技术研究中心/江西离子型稀土工程技术研究有限公司,江西赣州341000 [2]江西理工大学资源与环境工程学院,江西赣州341000

出　　处：《中国稀土学报》2024年第2期275-283,I0003,共10页Journal of the Chinese Society of Rare Earths

基　　金：国家重点研发计划项目(2021YFC2902201);江西省科技创新平台组建项目(20194AFD45003);江西省重点研发计划项目(20212BBG73015)资助。

摘　　要：(NH_(4))_(2)SO_(4)柱浸过程中铵与稀土在矿土内的分布行为研究能为浸矿剂硫酸铵用量估算提供理论参考。试验以定南某矿区某离子型稀土矿土为研究对象,采用室内柱浸和等比例分割取样分析方法,对(NH_(4))_(2)SO_(4)柱浸离子型稀土各阶段柱内矿土中铵与稀土的分布及传质行为进行了研究。结果发现,离子型稀土柱浸过程中的传质行为最终表现为铵与稀土离子在滞留水层和黏土颗粒表面双电层间的离子交换及滞留水层和流动水层间的物质传递过程,在柱浸过程中矿土内会形成一条“稀土浸出带”随浸出液向下渗透逐渐完成柱内矿土的浸取。离子型稀土黏土颗粒表面双电子层的扩散层可能存在空缺亚层,在柱浸过程中会对铵与稀土离子进行吸附,这也是黏土颗粒对稀土离子具有反吸附行为的原因。根据硫(NH_(4))_(2)SO_(4)柱浸过程中铵与稀土的分布规律及传质行为特征,推导出一种较为简便的估算离子型稀土浸取时(NH_(4))_(2)SO_(4)最低用量的方法,通过理论最低用量浸矿和电解质淋洗相结合的方式,可以获得较高的稀土浸出率,稀土产品品质与(NH_(4))_(2)SO_(4)单独浸矿基本一致,希望可以为赣南地区离子型稀土矿区早日复产和绿色开采提供理论参考。The distribution behavior of ammonium and rare earth during ammonium sulfate column leaching can provide a theoretical reference for the estimation of ammonium sulfate dosage.Ammonium sulfate column leaching of ionic rare earth in a mining area in Dingnan,Jiangxiprovince,was carried out,and the distribution and mass transfer behavior of ammonium and rare earth at each stage were investigated by using indoor column leaching and equiproportional split sampling and analysis methods.The results indicate that the mass transfer behavior of column leaching finally exhibits as a process of ion exchange between ammonium and rare earth ions in the stagnant water layer and the bilayer on the surface of clay particles,and mass transfer between the stagnant water layer and the flowing water layer.During the column leaching process,a"rare earth leaching zone"would be formed in the mineral soil,which will gradually complete the leaching of the mineral soil in the column with the downward penetration of the leaching solution.There may exist a vacant sublayer in the diffusion layer of the double electron layer on the surface of ionic rare earth clay particles,which adsorbs ammonium and rare earth ions during column leaching.This is the reason why the clay particles have an antisorption behavior for rare earth ions.Based on the distribution and mass transfer behavior of ammonium and rare earth a simpler method of estimating the minimum dosage of ammonium sulfate was deduced.A high rare earth leaching rate can be obtained by combining the theoretical minimum dosage of leaching agent and electrolyte drenching,and the quality of rare earth products is consistent with that by ammonium sulfate leaching alone,which is hoped to provide theoretical reference for the early resumption of production and green mining of ionic rare earth mines in Gannan area.

关 键 词：离子型稀土 浸出 传质行为 

分 类 号：X53[环境科学与工程—环境工程]