拜耳法赤泥中钪、钇浸出行为及动力学研究
Leaching Behavior and Kinetics of Scandium and Yttrium from Bayer Red Mud
黄魁 1丁艳 2唐启桁 2李汝桂 2单馨可 2卢远桓 2卢思妍2
作者信息
- 1. 广西大学 资源环境与材料学院,广西 南宁 530004;广西高校环境保护重点实验室,广西 南宁 530004
- 2. 广西大学 资源环境与材料学院,广西 南宁 530004
- 折叠
摘要
采用两步酸浸法浸出赤泥中的钪和钇,用磷酸对赤泥进行一段酸浸,实现脱碱和脱硅并富集稀土金属钪、钇;用硫酸对磷酸浸出渣进行二段酸浸,考察了硫酸浓度、液固比、反应温度、反应时间对钪、钇浸出过程的影响,并进行了浸出动力学分析.结果表明,赤泥经磷酸浸出后,脱碱和脱硅效果较好,K、Na、Si浸出率分别为 75.62%、87.82%、80.25%;在硫酸浓度 2.5 mol/L、液固比7∶1、反应温度 70℃、反应时间 45 min条件下进行二段硫酸浸出,Sc、Y平均浸出率分别为 74.49%、80.02%.Sc和Y的硫酸浸出过程均符合多相液固区域反应模型,受扩散控制,表观反应活化能分别为 18.50 kJ/mol和 16.74 kJ/mol.
Abstract
A two-step acid leaching process was used to leach scandium and yttrium from red mud.Phosphoric acid was used in the first stage of leaching to achieve dealkalization,desilication and enrichment of rare earth elements(scandium and yttrium).Then,the leaching residue was leached with sulfuric acid in the second stage.The effects of sulfuric acid concentration,liquid-solid ratio,reaction temperature and reaction time on the leaching process of scandium and yttrium were investigated,and the leaching kinetics was also analyzed.It is found that leaching of red mud with phosphoric acid can bring better dealkalization and desilication effect,showing the leaching rates of K,Na and Si at 75.62%,87.82%and 80.25%,respectively.Then,in the second stage of leaching process with sulfuric acid concentration of 2.5 mol/L and liquid-solid ratio of 7∶1,reaction runs at 70 ℃ for 45 min,leading to the average leaching rates of Sc and Y up to 74.49%and 80.02%,respectively.It is shown that the leaching processes of Sc and Y with sulfuric acid follow the liquid-solid reaction model,which is controlled by diffusion,and the apparent reaction activation energies are calculated to be 18.50 kJ/mol and 16.74 kJ/mol,respectively.
关键词
拜耳法赤泥/酸浸/钪/钇/动力学/磷酸浸出/硫酸浸出Key words
Bayer red mud/acid leaching/scandium/yttrium/kinetics/phosphoric acid leaching/sulfuric acid leaching引用本文复制引用
基金项目
国家自然科学基金(21767003)
国家级大学生创新创业训练计划支持项目(202210593083)
出版年
2024
NETL
NSTL
万方数据