One-step separation and recovery of rare earth and iron from NdFeB slurry via phosphoric acid leaching

作     者：Ling He Qipeng Xu Wensheng Li Qizheng Dong Weimin Sun Ling He;Qipeng Xu;Wensheng Li;Qizheng Dong;Weimin Sun

作者机构：State Key Laboratory of Advanced Processing and Recycling of Nonferrous MetalsLanzhou University of TechnologyLanzhou 730050China School of Materials Science and EngineeringLanzhou University of TechnologyLanzhou 730050China 

出 版 物：《Journal of Rare Earths》 (稀土学报（英文版）)

年 卷 期：2022年第40卷第2期

页      面：338-344,I0006页

核心收录：

学科分类：080602[工学-钢铁冶金] 080603[工学-有色金属冶金] 0709[理学-地质学] 0819[工学-矿业工程] 08[工学] 0806[工学-冶金工程] 0708[理学-地球物理学] 0703[理学-化学] 

基　　金：Project supported by the Key Research and Development of Gansu Province,China(17JR7GA014) the National Natural Science Foundation of China(52075234) 

主　　题：NdFeB slurry Phosphoric acid leaching Iron Rare earth elements Oxalic acid 

摘      要：The recovery of rare earth elements(REEs)from NdFeB slurry by traditional hydrometallurgy has been limited becuase a large number of REEs are lost during separation together with *** this paper,a simple and sustainable method is proposed to efficiently separate and recover REEs and iron from NdFeB *** were recovered by one-step selective precipitation in phosphoric acid,and the dissolved iron was recovered by oxalic *** acid leaching results show that under the conditions of 4 mol/L phosphoric acid,80℃,L/S of 30:1 and 90 min,the leaching efficiencies of Fe and REEs reach 98.76%and1.09%,*** the rest of REEs remained in the leaching residue in the form of REEPO_(4)·nH_(2)O *** mixed rare earth oxide(rare earth oxalate roasted at 800℃)and FeC_(2)O_(4)·2 H_(2)O are obtained by oxalic acid precipitation with purities of 99.49%and 97.17%from the REEPO4·nH_(2)O dissolving solution and the phosphoric acid leaching ***,the phosphoric acid is regenerated while recovering iron,and it can be reused in the phosphoric acid leaching step after removing the impurity C_(2)O_(4)^(2-).In summary,this work provides an efficient and environmentally friendly method for recovering REEs and iron from NdFeB slurry waste.