Migration behavior, separation and recycling of rare earth during thermal decomposition of Zhijin phosphorus ore

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

作者机构：College of Resource and Environmental Engineering Guizhou University Guiyang 550025 China Guizhou Institute of Metallurgical aud Chemical Engineering Guiyang 550002 China School of Chemistry and Chemical Engineering Guizhou University Guiyang 550025 China 

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

年 卷 期：2018年第36卷第11期

页      面：1205-1211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：Project 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 phosphorus ore Rare earth Thermal decomposition Migration behavior Separation 

摘      要：Zhijin phosphorus ore is a moderate and low-grade phosphorus rare-earth ore contained in mines. The separation and extraction of associated rare earth are important research topics. In this study, the migration behavior of rare earth during the thermal decomposition of Zhijin phosphorus ore and the separation and extraction of rare earth in phosphorus slag are discussed systematically. During the thermal decomposition process of phosphorus ore, almost all of the associated rare earth enters into the phosphorus slag phase but does not enter into the ferrophosphorus or gas phases. Amorphous calcium metasilicate and calcium fluosilicate are major components of phosphorus slag, and rare earth mainly exists as a calsil solid solution. Hydrochloric acid was used for acidolysis of the phosphorous slag. Under the following conditions, 96% of the rare earth in the phosphorous slag can be dissolved in the acidolysis solution： acid excess coefficient of 1.5, reaction time of 50 min and reaction temperature of 50℃. The rare earth in the acidolysis solution was separated and recycled using oxalic acid as a precipitator and NaOH as a pH modifier. At pH of 1.7, rare-earth-enriched matter with rare-earth content of 2.1 wt% was obtained, and the recovery of the rare earth was 88%.