Selective leaching of calcium from mechanically activated mixed rare earth concentrate  

作　　者：Jiang Liu Bingxue Chen Yuanqi Feng Yijun Cao Yukun Huang Yuan Shi Meng Li 

机构地区：[1]Zhongyuan Critical Metals Laboratory,School of Chemical Engineering,Zhengzhou University,Zhengzhou,450001,China [2]State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals,Lanzhou University of Technology,Lanzhou,730050,China

出　　处：《Journal of Rare Earths》2024年第6期1149-1156,I0006,共9页稀土学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(52004252);Natural Science Foundation ofHenan Province(222300420548);Strategic Research and Consulting Project of Chinese Academy of Engineering(2022-XBZD-07)。

摘　　要：The loss of rare earths(REs)takes place during the pre-decalcification process of mixed rare earth concentrate.In an effort to reduce such RE loss,a novel idea to improve the leaching selectivity of Ca to REs by applying selective mechanical activation was proposed.First,regarding the key minerals affecting the leaching selectivity of Ca to REs,the differences in the mechanical activation behaviors of CaF_(2) and REFCO_(3) were studied,and we find that the lattice strain of CaF_(2) increases from 0.21%to 0.42%,whereas that of REFCO_(3) increases from 0.31%to 0.40%.Notably,CaF_(2) demonstrates a larger lattice strain than REFCO_(3),indicating greater mechanical activation energy storage and higher leaching activity.Next,the HCl leaching process was studied.A significant leaching selectivity of Ca to REs,from 21.6 to 35.1,is achieved through mechanical activation.The Ca leaching rate reaches 80.7%when the RE loss is 2.3%in the activated sample.This study provides an novel approach for achieving selective extraction of specific components via mechanical activation pretreatment.

关 键 词：Mixed rare earth concentrate Pre-decalcification Selective mechanical activation Selective leaching 

分 类 号：TF845[冶金工程—有色金属冶金]