Phase transition of bastnaesite concentrate in calcification process  

作　　者：Yu-Kun Huang Ting-An Zhang Zhi-He Dou Jiang Liu Fang-Fang Tang 

机构地区：[1]Key Laboratory of Ecological Metallurgy of Multi-Metal Intergrown Ores of Ministry of Education, School of Materials and Metallurgy, Northeastern University

出　　处：《Rare Metals》2016年第8期649-654,共6页稀有金属（英文版）

基　　金：financially supported by the National Basic Research Program of China (No. 2012CBA01205)

摘　　要：The phase transformation in calcification process was investigated by X-ray diffraction （XRD） and differential scanning calorimeter （DSC）, and the effect of calcification on the leaching rate of rare earth was analyzed. The results show that bastnaesite transforms into rare earth hydrate at the cal- cification temperature range of 225-300 ℃. However, this transition is verified to be an efficient reaction for the acti- vating bastnaesite when the temperature is higher than 200 ℃. The leaching rate of rare earth increases to 89.17 % for activating bastnaesite from 36.27 % for the bastnaesite, and it is the highest with calcification temperature of 250 ℃, which is consistent with the result of DSC analysis. The transition of rare earth oxyfluoride into RE（OH）3 is acceler- ated by the addition of NaOH according to the experiments of different calcification systems.The phase transformation in calcification process was investigated by X-ray diffraction （XRD） and differential scanning calorimeter （DSC）, and the effect of calcification on the leaching rate of rare earth was analyzed. The results show that bastnaesite transforms into rare earth hydrate at the cal- cification temperature range of 225-300 ℃. However, this transition is verified to be an efficient reaction for the acti- vating bastnaesite when the temperature is higher than 200 ℃. The leaching rate of rare earth increases to 89.17 % for activating bastnaesite from 36.27 % for the bastnaesite, and it is the highest with calcification temperature of 250 ℃, which is consistent with the result of DSC analysis. The transition of rare earth oxyfluoride into RE（OH）3 is acceler- ated by the addition of NaOH according to the experiments of different calcification systems.

关 键 词：BASTNAESITE Calcification transformation Solidfluoride reaction Mineral phase transition 

分 类 号：TF845[冶金工程—有色金属冶金]