一水硬铝石型铝土矿在KOH亚熔盐介质中的溶出行为  

Leaching Behavior of Diaspore Bauxite in KOH Sub-molten Salt

作　　者：马青霞[1,2] 张亦飞[1] 曹绍涛[1] 张懿[1] 

机构地区：[1]中国科学院过程工程研究所绿色过程与工程重点实验室,湿法冶金清洁生产技术国家工程实验室,北京100190 [2]中国科学院大学,北京100049

出　　处：《过程工程学报》2013年第3期391-396,共6页The Chinese Journal of Process Engineering

基　　金：国家自然科学基金资助项目(编号:21276258);国家高技术研究发展计划(863)基金资助项目(编号:2011AA060701)

摘　　要：采用KOH亚熔盐介质溶出中低品位一水硬铝石型铝土矿,考察了反应温度、碱矿比、初始KOH溶液浓度、反应时间及添加CaO对溶出后赤泥化学成分和物相的影响.结果表明,在反应温度220℃、碱矿质量比1.5、初始KOH溶液浓度50%(ω)、反应时间1h的条件下,Al2O3回收率可达81.4%,赤泥的铝硅质量比降至1.06,赤泥中硅主要以KAlSiO4形式存在.溶出过程中添加CaO不能提高Al2O3溶出率.进一步回收溶出后赤泥中的K2O和Al2O3,终赤泥中K2O含量降至0.61%,Al2O3含量降至8.09%,Al2O3总回收率可达90.7%.The leaching behavior of diaspore bauxite in KOH sub-molten was investigated. The effects of reaction temperature, mass ratio of alkali to ore, initial KOH solution concentration, reaction time and CaO addition were examined. The results indicate that the recovery rate of Al2O3 can reach 81.4% and mass ratio of Al2O3 to SiO2 of the red mud decreases to 1.06 under the optimum conditions of reaction temperature at 220℃, mass ratio of alkali to ore at 1.5, initial KOH solution concentration of 50%（w） and reaction time for lh. The XRD analysis shows that Si exists in the form of KA1SiO4 in the red mud. Further study implies that CaO addition is not beneficial to the leaching process. A further step for extraction of K2O and Al2O3 in the red mud achieves good results with 0.61% of K2O, 8.09% of Al2O3 in the final red mud and 90.7% of Al2O3 overall leaching rate.

关 键 词：一水硬铝石 亚熔盐法 KOH 溶出 AL2O3 K2O 

分 类 号：TQ133.1[化学工程—无机化工]