(中國地質(zhì)大學(xué)材料科學(xué)與工程學(xué)院，北京100083)
摘 要: 以四川某地鋰云母礦石經(jīng)選礦預(yù)處理所得鋰云母精礦為原料，研究在硫酸介質(zhì)中鋰云母的分解反應(yīng)過程。結(jié)果表明：在硫酸濃度為4.2 mol/L、硫酸與鋰云母液固質(zhì)量比為3:1、溫度為433 K、轉(zhuǎn)速為30 r/min條件下反應(yīng)4 h，Li2O的溶出率達(dá)96%。反應(yīng)動力學(xué)實驗結(jié)果表明：鋰云母酸解反應(yīng)屬于固膜擴(kuò)散控制，分解過程符合液-固單顆粒反應(yīng)模型中的縮芯模型；反應(yīng)的表觀活化能為Ea為28.3 kJ/mol，阿倫尼烏斯常數(shù)k0為2.608，反應(yīng)級數(shù)n為0.998。
關(guān)鍵字: 鋰云母；分解反應(yīng)；動力學(xué)；硫酸介質(zhì)
（School of Materials Science and Technology, China University of Geosciences, Beijing 100083, China）
Abstract:The decomposition of lepidollite in sulfuric acid solution was studied and the lepidolite concentrate from Sichuan province was obtained by mineral separation pretreatment and its kinetics were studied. The results reveal that the dissolution rate of Li2O in the lepidolite sample reaches 96% when it was hydrothermal-treated at 433 K for 4 h, with the sulfuric acid concentration of 4.2 mol/L, the sulfuric acid lepidolite liquid to solid mass ratio of 3:1, and the stirring speed of 30 r/min, respectively. The kinetics research results indicate that the reaction of the lepidolite decomposition in sulfuric acid solution is controlled by solid membrane diffusion, and the decomposition conforms to the shrinking core model of the liquid-solid single particle reaction model, with the apparent activation energy (Ea) of 28.3 kJ/mol, the Arrhenius constant k0 of 2.608, and the reaction series n of 0.998.
Key words: lepidolite; decomposition reaction; kinetics; sulfuric acid solution
