文献类型：期刊文献

英文题名：Leaching kinetics and mechanism of alunite from alunite tailings in highly concentrated KOH solution

作者：Luo, Meng-Jie[1];Liu, Cheng-Lin[1];Xue, Jin[1];Li, Ping[1];Yu, Jian-Guo[1]

机构：[1]East China Univ Sci & Technol, Coll Chem Engn, Natl Engn Res Ctr Integrated Utilizat Salt Lake R, State Key Lab Chem Engn, Shanghai 200237, Peoples R China

年份：2017

卷号：174

起止页码：10

外文期刊名：HYDROMETALLURGY

收录：;EI(收录号：20173904214851);WOS:【SCI-EXPANDED(收录号:WOS:000416195200002)】；

基金：The authors wish to acknowledge National Nature Science Foundation of China (Grant 21376085, 21276080) and the Fundamental Research Funds for the Central Universities (Grant 22A201514058, 222201717008) for the financial support.

语种：英文

外文关键词：Alunite leaching; Alunite tailing; KOH; Dissolution mechanism; Leaching kinetics

摘要：Alunite tailings, a secondary resource from copper metallurgy industry in China, are considered a potential resource for both the production of alumina and potash fertilizer, since alunite tailings contain abundant alunite with associated impurities of kaolinite, dickite and quartz. In this work, the direct leaching of alunite from alunite tailings in the highly concentrated KOH solution is proposed. Under appropriate leaching conditions, such as temperature below 90 degrees C and KOH concentration above 13.5 mol.L-1, most of alunite is dissolved while kaolinite, dickite and quartz are still remained in the residue. Mastersizer, X-ray diffraction, infrared radiation spectrometer, Raman spectrometer and scanning electron microscopy/energy-dispersive spectroscopy are used to characterize alunite tailings samples before and after leaching. The leaching kinetics of alunite from alunite tailings in the concentrated KOH solution is described using a shrinking core model controlled by the surface chemical reaction. The key kinetics parameters, such as the activated energy and the reaction order, are determined based on the leaching experimental data. The dissolution mechanism of alunite from alunite tailings in the concentrated KOH solution is considered, and is used to account for the reaction order.