硫酸镁浸出离子型稀土矿动力学研究  

Leaching Kinetics of Ionic Rare Earth Ore with Magnesium Sulfate

作　　者：黄金 杨幼明 邓扬悟 王林生[1] 王慧娟 黄紫彬 Huang Jin;Yang Youming;Deng Yangwu;Wang Linsheng;Wang Huijuan;Huang Zibin(National Engineering Research Center for Ionic Rare Earth,Jiang Xi Ionic Rare Earth Engineering Research Co.,Ltd.,Ganzhou 341000,China;Faculty of Metallurgy and Chemical Engineering,Jiangxi University of Science and Technology,Gartzhou 341000,China;Faculty of Resource and Environmental Engineering,Jiangxi University of Science and Technology,Ganzhou 341000,China)

机构地区：[1]江西离子型稀土工程技术研究有限公司国家离子型稀土资源高效开发利用工程技术研究中心,江西赣州341000 [2]江西理工大学冶金与化学工程学院,江西赣州341000 [3]江西理工大学资源与环境学院,江西赣州341000

出　　处：《稀有金属》2022年第2期265-272,共8页Chinese Journal of Rare Metals

基　　金：国家重点研发计划项目(2019YFC0605004);国家科技部“863”计划项目(2012AA061901);江西省重点研发计划项目(20181BBG78076)资助。

摘　　要：为提高硫酸镁作为浸矿剂浸出稀土时的稀土浸出效率,对其浸出动力学进行研究。采用搅拌浸出的方式进行动力学实验,明晰浸出过程动力学控制步骤,并结合Arrhenius方程求取反应的表观活化能及动力学方程,此外,考察了浸出温度、硫酸镁浓度、搅拌速度以及矿石粒径对稀土浸出过程的影响。结果表明:硫酸镁浸出离子型稀土矿动力学符合未反应收缩核模型,浸出过程受内扩散控制,稀土浸出反应的表观活化能为9.38 kJ·mol^(-1),其动力学方程可表示为:1-2/3θ-(1-θ)^(2/3)=0.428×r_(0)^(-0.546)×e^(-9380/RT)×t;浸矿过程中提高浸出温度、减小粒径都有助于提高稀土浸出率、加快浸出速度、缩短浸出时间,建议在温度较高的夏、秋季节进行矿山生产;搅拌速度对稀土浸出无明显影响;硫酸镁浓度对稀土浸出有阶段性影响,当硫酸镁浓度低于2%(质量分数)时,提高硫酸镁浓度可促进稀土浸出,但硫酸镁浓度超过3%后,硫酸镁浓度对浸出影响较小,合适的硫酸镁浓度可控制在2%~3%。Nowadays,the process of ammonium sulfate leaching and ammonium bicarbonate precipitation was widely used to extract rare earth from ionic rare earth ores.However,it would lead to serious ammonia nitrogen pollution problems.With the improvement of environmental protection requirements,new studies had been focused on the development of non-ammonium leaching agents.The rare earth leaching rate of magnesium sulfate had been shown similar to that of ammonium sulfate,but the leaching time was longer and the rare earth concentration of the leaching solution was lower.Magnesium sulfate was used as leaching agent to study the kinetics of leaching process,and the influences of ore particle size and leaching conditions on the leaching process were investigated,so as to provide some theoretical basis for taking measures to strengthen the leaching process and improve the leaching efficiency.A set of devices including three-necked bottle,water bath pot and agitator was designed for experiment.A total of 250 ml of a certain concentration of magnesium sulfate solution was put in the three-necked flask and heated to a desired leaching temperature.50 g of rare earth ore was placed into the three-necked flask,and then the agitator was set to stir at a certain speed.Samples were collected at the predetermined reaction time point,and the concentration of rare earth was determined by ethylene diamine tetraaceticacid(EDTA)titration.After that,the leaching rate was calculated.The kinetic model of magnesium sulfate leaching process was established,then the experimental data were substituted into the relevant kinetic equations to reveal the kinetic control steps of the leaching process,and the apparent activation energy and kinetic equations of the reaction were obtained by combining the Arrhenius equation.Moreover,the effects of leaching temperature,magnesium sulfate concentration,stirring speed and ore particle size on leaching kinetics were investigated by single factor experiment.The results of the dynamics experiment were as follows:

关 键 词：离子型稀土矿 动力学 硫酸镁 

分 类 号：TF845[冶金工程—有色金属冶金]