从抛光废料中回收稀土  

Recovery of Rare Earths from Polishing Waste

作　　者：张宇 Zhang Yu(Lianyungang Gaopin Renewable Resources Co.,Ltd,Lianyungang,Jiangsu,China)

机构地区：[1]连云港高品再生资源有限公司,江苏连云港222302

出　　处：《矿产综合利用》2023年第5期32-35,46,共5页Multipurpose Utilization of Mineral Resources

摘　　要：这是一篇冶金工程领域的论文。以稀土抛光粉废料为原料,通过正交实验设计,首先进行废料与硫酸铵和硫酸氢铵混合物的焙烧实验,使稀土氧化物转化为硫酸盐。实验考查3个因素,每个因素取3个水平,选用正交表L_(9)(3^(4)),安排了9个实验,统计分析实验结果:焙烧温度取480℃,焙烧时间取3 h,质量比取1.8∶1。然后在酸浸液中加入0.2%的硫脲作还原剂,研究用稀硫酸从焙烧固相中浸出稀土的工艺条件。实验考查4个因素,每个因素取4个水平,选用正交表L_(16)(4^(5)),安排了16个实验,统计分析实验结果:酸浸温度取90℃,硫酸浓度取0.5 mol/L,浸出时间取4 h,稀硫酸与焙烧固相的液固比(质量)取4:1,稀土的浸出率可达97.8%~98.0%。This is an essay in the field of metallurgical engineering.Using rare earth polishing powder waste as raw material,an orthogonal experimental design was used to convert rare earth oxides into sulfates by first conducting roasting experiments of the waste with a mixture of ammonium sulfate and ammonium bisulfate.The orthogonal experiment with 3 factors and 3 levels was carried out by using the orthogonal table L_(9)(3^(4))and statistically analyzed the test results:the roasting temperature was 480℃,the roasting time was 3 h,and the mass ratio was 1.8:1.In the second step,0.2%thiourea was added to the acid leaching solution as reducing agent,and the technological conditions of leaching rare earth from the calcined solid phase with dilute sulfuric acid were studied.The orthogonal experiment with 4 factors and 4 levels was carried out by using the orthogonal table L_(16)(4^(5)).The experimental result shows that on the condition of lixiviating temperature being 90℃,sulfuric acid thickness being 0.5 mol/L,lixiviating time being 4 h,liquid-to-solid quality ratio being 4∶1,the extraction rate of rare earths will reach 97.8%~98.0%in mass fraction.

关 键 词：冶金工程 焙烧 稀土抛光粉废料 稀土浸出率 正交实验设计 

分 类 号：TD985[矿业工程—选矿] TF803.2[冶金工程—有色金属冶金]