摘要
粉煤灰既是一种大宗固体废弃物,也是一种含有多种稀散金属元素的重要二次资源。本文提出细磨预处理—钠化焙烧—盐酸酸浸流程综合提取稀散金属元素的工艺路线,并对工艺参数进行系统优化。研究结果表明:粉煤灰经15 min细磨预处理,在碳酸钠添加量为粉煤灰质量的37.5%、于850℃焙烧2 h后,采用3 mol/L盐酸于温度为80℃、液固比为10 mL/g条件下浸出90 min,Li、Ga、V的浸出率分别达到89.98%、86.74%和83.27%;碳酸钠在高温焙烧过程中促使粉煤灰中难溶的玻璃微珠、莫来石及石英等矿物相转化为可溶性的霞石和偏硅酸钠,实现了粉煤灰中稀散金属的释放。
The comprehensive extraction of rare metal elements from fly ash was explored,which served as both a significant solid waste and a valuable secondary resource containing various trace metals.A novel process comprising fine grinding pretreatment,sodium roasting,and hydrochloric acid leaching was introduced,and the optimization of its parameters was investigated.The results show that after a 15 min fine grinding step,the amount of sodium carbonate is 37.5%of the raw material mass.After roasting at 850℃for 2 h,the subsequent leaching with 3 mol/L hydrochloric acid at 80℃with a liquid-to-solid ratio of 10 mL/g for 90 min,leads to leaching efficiencies of 89.98%,86.74%,and 83.27%for Li,Ga and V,respectively.The sodium carbonate facilitates the transformation of insoluble mineral phases,such as glass microspheres,mullite and quartz into soluble feldspathoid and sodium metasilicate during the roasting process,thereby releasing the trace metals from the fly ash.
作者
尉子夜
朱德庆
潘建
杨聪聪
郭正启
李思唯
YU Ziye;ZHU Deqing;PAN Jian;YANG Congcong;GUO Zhengqi;LI Siwei(School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China)
出处
《中南大学学报(自然科学版)》
北大核心
2025年第8期3126-3138,共13页
Journal of Central South University:Science and Technology
基金
国家重点研发计划项目(2023YFC3903904)。
关键词
粉煤灰
焙烧活化
酸浸
综合提取
稀散金属
fly ash
roasting activation
acid leaching
comprehensive extraction
rare metals
