Dissolution characteristics of sericite in chalcopyrite bioleaching and its effect on copper extraction  

作　　者：Ying-bo Dong Hao Li Hai Lin Yuan Zhang 

机构地区：[1]School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China

出　　处：《International Journal of Minerals,Metallurgy and Materials》2017年第4期369-376,共8页矿物冶金与材料学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(No.51204011);the Science and Technology Project for the Guidance Teacher of Beijing Excellent Doctoral Dissertation(No.20121000803)

摘　　要：The effects of sericite particle size, rotation speed, and leaching temperature on sericite dissolution and copper extraction in a chalcopyrite bioleaching system were examined. Finer particles, appropriate temperature and rotation speed for Acidithiobacillus ferrooxidans resulted in a higher Al3+dissolution concentration. The Al3+dissolution concentration reached its highest concentration of 38.66 mg/L after 48-d leaching when the sericite particle size, temperature, and rotation speed were −43 μm, 30°C, and 160 r/min, respectively. Meanwhile, the sericite particle size, rotation speed, and temperature can affect copper extraction. The copper extraction rate is higher when the sericite particle size is finer. An appropriately high temperature is favorable for copper leaching. The dissolution of sericite fitted the shrinking core model, 1–(2/3)α–(1–α)2/3= k1t, which indicates that internal diffusion is the decision step controlling the overall reaction rate in the leaching process. Scanning electron microscopy analysis showed small precipitates covered on the surface of sericite after leaching, which increased the diffusion resistance of the leaching solution and dissolved ions. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg.The effects of sericite particle size,rotation speed,and leaching temperature on sericite dissolution and copper extraction in a chalcopyrite bioleaching system were examined. Finer particles,appropriate temperature and rotation speed for Acidithiobacillus ferrooxidans resulted in a higher Al^(3+) dissolution concentration. The Al^(3+) dissolution concentration reached its highest concentration of 38.66 mg/L after 48-d leaching when the sericite particle size,temperature,and rotation speed were-43 μm,30°C,and 160 r/min,respectively. Meanwhile,the sericite particle size,rotation speed,and temperature can affect copper extraction. The copper extraction rate is higher when the sericite particle size is finer. An appropriately high temperature is favorable for copper leaching. The dissolution of sericite fitted the shrinking core model,1 –(2/3)a –(1 – a)^(2/3) = k_1 t,which indicates that internal diffusion is the decision step controlling the overall reaction rate in the leaching process. Scanning electron microscopy analysis showed small precipitates covered on the surface of sericite after leaching,which increased the diffusion resistance of the leaching solution and dissolved ions.

关 键 词：Aluminum BIOLEACHING COPPER Dissolution EXTRACTION Leaching Rotation Scanning electron microscopy SHRINKAGE 

分 类 号：TF18[冶金工程—冶金物理化学] TF811