无还原剂时脉石在Na_2CO_3-NaCl低温熔盐体系中的反应行为研究  

Reaction Behavior of Gangue in Na_2CO_3-NaCl Molten Salt System without Reductant

作　　者：叶龙刚[1] 唐朝波[1] 陈永明[1] 杨声海[1] 唐谟堂[1] 刘勇强[1] 

机构地区：[1]中南大学冶金与环境学院,湖南长沙410083

出　　处：《矿冶工程》2014年第2期73-76,共4页Mining and Metallurgical Engineering

基　　金：国家自然科学基金资助(51104128;51234009);十二五国家科技支撑计划项目(2012BAC12802)

摘　　要：在热力学理论计算的基础上，用XRD分析和TG-DSC热分析技术研究了在无还原剂存在时Si02、CaCO3、Al2O3在Na2CO3-NaCl低温熔盐体系中的反应行为。研究结果表明，Al2O3与熔盐在700℃以上时全部生成了铝酸钠；二氧化硅在900℃时全部生成了可溶性的Na2SiO3，900℃以下则反应缓慢；CaCO3在500-900℃基本不分解，但会与Na2CO3结合成高温下不稳定的Na2Ca（CO3）2。实验结果与热力学计算结果相符合。Behaviors of gangue SiO2, CaCO3 and Al2O3 in Na2CO3-NaCl molten salt system without reductant were investigated using XRD and TG-DSC analysis methods based on thermodynamic calculations. The results showed that sodium aluminate was generated by a complete reaction between A1203 and the molten salt at 700 ℃. SiO2 reacted with Na2CO3 to form soluble NaESiO3 at 900℃, but the reaction rate was slow at a temperature below 900 ℃. CaCO3 hardly decomposed at 500-900 ℃, but combined with Na2CO3 to form Na2Ca（ CO3 ）2 which is unstable at high temperature. The experimental results are consistent with the thermodynamic calculations.

关 键 词：低温熔盐熔炼 脉石 热力学分析 

分 类 号：TF801[冶金工程—有色金属冶金]