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

作　　者：阳启华 吴金玲 王日 张文娟[2] Yang Qihua;Wu Jinling;Wang Ri;Zhang Wenjuan(Liangshan Rare Earth Co.,Ltd.,China Rare Earth Group Co.,Ltd.,Liangshan 615000,China;School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[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

出　　处：《中国稀土学报》2024年第5期955-961,I0004,共8页Journal of the Chinese Society of Rare Earths

基　　金：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)资助。

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、H_(2)O_(2)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:H_(2)O_(2)浓度333.00 g·L^(-1),浸出温度75℃,底液HCl浓度0.71 mol·L^(-1),H_(2)O_(2)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(Fe_(2)O_(3),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晶型羟基氧化铁。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 H_(2)O_(2) concentration,leaching temperature,base HCl concentration,H_(2)O_(2) flow rate,final pH value,L/S ratio etc.The results indicate that the proper conditions are 333.00 g·L^(-1)of H_(2)O_(2) concentration,75℃of leaching temperature,0.71 mol·L^(-1)of the base HCl concentration,29.40×10^(-3) g·min^(-1)of H_(2)O_(2) flow rate,3.0-3.5 of final pH value,4.56 mL/g at L/S ratio.The corresponding leaching rate of rare earth oxide(REO)is 99.26%,Pr-Nd oxide is 99.52%,cobalt is 90.53%,and s(Fe_(2)O_(3),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 

分 类 号：TF845.6[冶金工程—有色金属冶金]