羟基氧化铁分离法回收钕铁硼废料的实验研究
Recovery of Rare Earth from Spent NdFeB Magnets by Iron Oxyhydroxide Separation Method
阳启华 1吴金玲 1王日 1张文娟2
作者信息
- 1. 中稀(凉山)稀土有限公司,四川凉山 615000
- 2. 北京科技大学冶金与生态工程学院,北京 100083
- 折叠
摘要
钕铁硼废料是重要的稀土二次资源,其回收的技术难点在于稀土元素与主要杂质铁的有效分离.本研究采用羟基氧化铁分离法回收钕铁硼废料,通过控制浸出过程的双氧水浓度、浸出温度、底液HCl浓度、H2O2流量、终点pH值、液固比等条件,实现了稀土的选择性浸出.在工艺条件:H2O2浓度 333.00 g·L-1,浸出温度 75 ℃,底液 HCl 浓度0.71 mol·L-1,H2O2流量 29.40×10-3 g·min-1,终点pH值3.0～3.5,液固比4.56 mL/g,得到稀土氧化物(REO)浸出率99.26％,镨钕氧化物浸出率99.52％,Co浸出率90.53％,酸浸液浸出选择性s(Fe2O3,REO)＜0.01％.酸浸渣沉淀过滤性好,XRD和SEM分析表明,酸浸渣的主要物相为品型羟基氧化铁.
Abstract
Spent NdFeB magnets are important secondary rare earth resource.Its recycling remains a challenge due to the keytechnical difficulties of separating rare earth elements(REEs)from the major impurity Fe.In the present study,the iron oxyhydroxide separation method for recycling spent NdFeB magnets was studied.And a highly selective leaching of REEs can be obtained by controlling H2O2 concentration,leaching temperature,base HC1 concentration,H2O2 flow rate,final pH value,US ratio etc.The results indicate that the proper con-ditions are 333.00 g·L-1 of H2O2 concentration,75 ℃ of leaching temperature,0.71 mol·L-1 of the base HC1 concentration,29.40×10-3 g·min-1 of H2O2 flow rate,3.0-3.5 of final pH value,4.56 mUg at US ratio.The cor-responding leaching rate of rare earth oxide(REO)is 99.26％,Pr-Nd oxide is 99.52％,cobalt is 90.53％,and s(Fe2O3,REO)in the leaching solution is less than 0.01％.The leaching residue is easy to precipitate and filter,since its main phase is crystalline iron oxyhydroxide(FeOOH)based on the XRD and SEM results.
关键词
钕铁硼废料/羟基氧化铁分离法/浸出率/浸出选择性Key words
spent NdFeB magnets/iron oxyhydroxide separation method/leaching rate/leaching selectivity引用本文复制引用
基金项目
中央高校基本科研业务费项目(FRF-TP-19-036A2)
中国博士后科学基金(2018T110045)
出版年
2024
NETL
NSTL
万方数据