以工业级Li2CO3为原料,采用碳化分解法提纯制备电池级纯度Li2CO3。研究了碳化时间、固液比和CO2气体流速3个因素对Li2 CO3提纯过程中纯度、产率以及杂质钙镁铁去除效果的影响。最佳工艺条件为碳化时间30 min,固液比1∶30,CO2气体流速4 L/min。结果表明,通过碳化分解法可使粗级Li2CO3产品的纯度由90%提高到99.75%以上,产率达到78%以上,满足了电池级Li2CO3的要求。
Battery grade Li2CO3 was prepared by carbonation-decomposition using the industry-grade Li2CO3,and the effect of carbonation conditions,such as carbonation time,ratio of solid to liquid and CO2 flow rate,on the purification,productivity of Li2CO3 and the impurities removal of calcium,magnesium and iron was investigated.The optimum conditions is carbonation time 30 min,the ratio of solid to liquid 1 ∶ 30,CO2 flow rate 4 L/min.Results showed that the purity of Li2CO3 can be increased from 90% to more than 99.75% by carbonation-decomposition method,and the productivity of the purified Li2CO3 can reach more than 78%.The properties of purified Li2CO3 can meet the requirement of raw material for lithium ion battery.