摘要
硫酸盐焙烧-水浸法处理锂云母精矿后,水浸液中含有大量钙、镁、钾、钠等杂质元素。本文以湖南某锂云母冶炼企业的水浸液为研究对象,采用化学沉淀法进行除杂试验,考察了碳酸钠直接除杂、使用氧化钙或氢氧化钠调节pH后添加碳酸钠两种方式,并进一步探究了氧化钙用量、碳酸钠用量、反应时间、反应温度及除杂试剂添加方式对除杂效果的影响,得到以下主要结论。采用碳酸钠直接去除杂质时,在碳酸钠理论用量倍数为2的条件下,钙离子含量脱除至21.4 mg/L,镁离子含量脱除至43.3 mg/L,锂损失率为6.6%;采用调节pH后添加碳酸钠去除杂质时,首先调节浸出液pH值至11.63,常温下连续搅拌1 h后液固分离,然后向调节pH后液添加理论量1.5倍20%碳酸钠溶液,90℃下搅拌1 h后,液固分离,钙离子脱除至12.8 mg/L,镁离子浓度降低至0.1 mg/L以下,锂损失率为2.1%。本文提出的分步过滤、调pH后再用碳酸钠除杂的方式处理锂云母水浸液,具有杂质去除效果好、锂损失率低且成本低的优势,为同类企业提锂工艺优化提供了参考和借鉴。
After the treatment of lepidolite concentrate by sulfate roasting-water leaching method,the water leaching solution contains a large amount of impurity elements such as calcium,magnesium,potassium and sodium.This study focuses on the leachate from a lithium mica smelting enterprise in Hunan Province,employing a chemical precipitation method for impurity removal.It examines two approaches:directly removing impurities with sodium carbonate and adding sodium carbonate after adjusting the pH with calcium oxide or sodium hydroxide.The effects of calcium oxide dosage,sodium carbonate dosage,reaction time,reaction temperature,and the method of adding removal agents on the impurity removal efficiency were investigated,leading to the following main conclusions.When impurities were removed directly using sodium carbonate at twice of the theoretical dosage,the calcium ion content was reduced to 21.4 mg/L,the magnesium ion content was reduced to 43.3 mg/L,and the lithium loss rate was 6.6%.When removing impurities by adding sodium carbonate after adjusting the pH,the pH of the leachate was primarily adjusted to 11.63,followed by continuous stirring at room temperature for 1 hour before solid-liquid separation.Then,20%sodium carbonate solution with dosage of 1.5 times of theoretical amount was added to the pH-adjusted liquid,and after stirring at 90℃for 1 hour and performing solid-liquid separation,the calcium ion content was reduced to 12.8 mg/L,the magnesium ion concentration fell below 0.1 mg/L,and the lithium loss rate was 2.1%.The stepwise filtration method proposed in this paper,involving adjusting the pH before using sodium carbonate for impurity removal from lithium mica leachate,demonstrates advantages of effective impurity removal,low lithium loss rate,and low cost,providing a reference for the optimization of lithium extraction processes in similar enterprises.
作者
薛祥
谢洪珍
王俊娥
王亮
匡晨
XUE Xiang;XIE Hongzhen;WANG June;WANG Liang;KUANG Chen(State Key Laboratory of Comprehensive Utilization of Low-Grade Refractory Gold Ores,Longyan 364200,China;Xiamen Zijin Mining and Metallurgy Technology Co.,Ltd.,Xiamen 361101,China;Zijin Mining Group Company Limited,Longyan 364200,China)
出处
《中国有色冶金》
北大核心
2025年第4期69-76,共8页
China Nonferrous Metallurgy
关键词
锂云母
水浸液
去除杂质
化学沉淀
钙离子
镁离子
锂损失率
分步过滤
lithium mica
leachate
impurity removal
chemical precipitation
calcium ions
magnesium ions
lithium loss rate
stepwise filtration
