Separation and recovery of associated rare earths from the Zhijin phosphorite using hydrochloric acid

作     者：Dengpan Nie An Xue Mingyang Zhu Yu Zhang Jianxin Cao 

作者机构：College of Resource and Environmental Engineering Guizhou University School of Chemical Engineering Guizhou Minzu University Guizhou Institute of Metallurgical and Chemical Engineering School of Chemistry and Chemical Engineering Guizhou University 

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

年 卷 期：2019年第37卷第4期

页      面：443-450页

核心收录：

学科分类：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：supported by Key Industrial Engineering Project of Guizhou Province(3041) High-level Talent Project of Guizhou Province(TZJF-2011-54) Guizhou Science and Technology Support Plan Project(2892) 

主　　题：Zhijin phosphorite mine Rare earths Leaching Separation Recovery 

摘      要：The separation and extraction of associated rare earths from the Zhijin phosphorite mine is of great interest. Based on previous studies, the hydrolysis of phosphate ore using hydrochloric acid was systematically studied through extensive testing. Experiments were conducted to separate and recover the rare earths from the hydrolysis solution. Kinetic studies on the acidolysis of phosphorite using hydrochloric acid show that the use of hydrochloric acid in the acidolysis of phosphorite is mainly controlled by a chemical reaction and is also a diffusion-controlled reaction. When 210 L of HCL per 100 kg of phosphorite was used at 30 ℃ for 360 min, 96.1% of the P_2 O_5 and 95.0% of the rare earths are leached from the phosphorite. After defluorination and purification, the pH of the phosphate-acid solution is adjusted to 2.1 using sodium hydroxide, and a rare earth concentrate with rare earth content of 1.76 wt%is obtained; i.e., 90.1% of the rare earths are recovered. The rare earth content is increased to more than5 wt% through multiple enrichment processes, with a total yield of 59.5%.