摘要
锂辉石矿中含有丰富的Li、Al、Si元素,传统的湿法浸出工艺仅对Li进行回收,造成Al、Si元素的浪费.本文提出了一种高附加值的锂辉石矿碳热还原新工艺,氧化铁作为助剂,在高温条件下使矿石中的Li挥发并冷凝富集,Si与Fe结合形成Si-Fe合金,Al富存于熔渣中.通过进一步的高温熔分分离渣与合金,回收富氧化铝渣.结果表明,氧化铁能显著促进锂辉石矿的还原.最佳反应条件为,进料中铁/硅的质量比不低于2、反应温度为1823 K、反应时间为8 h时,Li的还原率为97.56%,Si-Fe合金的直接产出率为85.12%.此外,冷凝物中氧化锂的含量可达到29.5%,约为锂辉石矿的10倍,可作为富锂精矿再利用.此方法实现了锂辉石矿中Li、Al、Si元素的综合分离与回收.
Abstract
The carbothermal reduction process of spodumene ore effectively separates Al and Si components from spodumene ore while also extracting lithium(Li).The high value-added sputum heat reduction process of spodumene ore was proposed.Fe2O3 was used as an auxiliary agent.Si is combined with Fe to form Si-Fe alloy and Al is enriched in the slag.The experimental results showed that the addition of Fe2O3 could significantly promote the carbothermal reduction of spodumene ore,when the mass ratio of Fe/Si is not less than 2.Experiments confirmed that the optimal experimental conditions were 1823 K and heated for 8 h.During the reduction process,the reduction rate of Li was higher than 90%,and the direct yield of Si-Fe alloy was higher than 85%.In addition,the content of Li in dust could reach 29.5%,about 16 times that of the spodumene ore.
基金项目
Academician Free Exploration Fund of Yunnan Province,China(2021HA006)
NETL
NSTL
维普
万方数据