Recovery of neodymium,dysprosium,and cobalt from NdFeB magnet leachate using an unsymmetrical dialkylphosphinic acid extractant,INET-3  

作　　者：Zhengyu Liu a Jiaming Wu a Xinyu Liu Wen Wanga Ziwei Li Ruijing Xu Yue Ding Junlian Wang 

机构地区：[1]School of Civil and Resource Engineering.University of Science and Technology Beijing,Beijing 100083,China [2]Shijiazhuang Vocational College of Technology&Information,Shijiazhuang 050091,China

出　　处：《Journal of Rare Earths》2020年第10期1114-1118,I0004,共6页稀土学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (51974026)。

摘　　要：Rare earths (REs) and Co are critical strategic resources.Their recovery is crucial for ensuring that their supplies are adequate and for reducing environmental pollution.End-of-life NdFeB magnets are important secondary RE sources.The separation of Dy,Nd,and Co from NdFeB leachate using a relatively new extractant (2,3-dimethylbutyl)(2,4,4’-trimethylpentyl)phosphinic acid (INET-3),was investigated in this study.The separation parameters,such as equilibrium pH,phase ratio,INET-3 concentration,and number of counter-current extraction stages,were optimised.The results show that INET-3 can separate Dy,Nd,and Co efficiently.For the preferential extraction of Dy from synthetic iron-free NdFeB leachate,the optimum equilibrium pH is 2.60.Under this condition,separation of Dy from the leachate requires four counter-current extraction stages at A/O (volume ratio of aqueous to organic)=1:2.This is demonstrated by a simulated four-stage counter-current extraction process.At equilibrium pH=2.52and A/O=1:2,98%of Dy is recovered with 95%purity.As to the subsequent separation of Nd from the leachate,nearly 100%is recovered with 99%purity through a simulated three-stage counter-current extraction process at equilibrium pH=5.33 and A/O=1:1.Approximately 95%of Co remains in the raffinate with 99.98%purity.

关 键 词：NdFeB RECOVERY INET-3 Extraction Separation Rare earths 

分 类 号：TF845[冶金工程—有色金属冶金] TF816