氯化锂与碳酸钠反应结晶制备碳酸锂的研究

中国主要以矿石为原料生产碳酸锂（Li2CO3），而从锂含量丰富的盐湖卤水中直接生产优质的碳酸锂产品具有广阔的前景。对氯化锂（LiCl）和碳酸钠（Na2CO3）反应结晶生产碳酸锂的过程做了研究，考察了碳酸钠加入量、搅拌速度、温度、氯化锂浓度、添加剂及加料方式对反应结晶过程的影响。得到了较佳的工艺条件：以反加料的方式进行反应，碳酸钠加入量为理论加入量的110%，搅拌速度为400 r/min，反应温度为80 ℃，c（LiCl）=3.2 mol/L。结果表明，搅拌转速对产品产率的影响不明显，碳酸钠加入量、温度和氯化锂浓度对产品的产率有影响，其中温度和氯化锂浓度的影响显著。加料方式和加入聚丙烯酸（PAA）作为添加剂可以得到不同的产品形貌；搅拌速度、反应温度、LiCl浓度以及PAA作为添加剂对Li2CO3纯度均有一定程度的影响。

Study on preparation of lithium carbonate via reactive crystallization from lithium chloride and sodium carbonate

China produced lithium carbonate from spodumene mostly.However，producing high quantity lithium carbonate from lithium-rich salt lakes has a vast potential for future development.The preparation process of lithium carbonate by reac- tive crystallization with sodium chloride and sodium carbonate was studied.The effects of Na2CO3 addition，stirring rate，reac- tion temperature，concentration of LiCl，feeding methods，and additive on the process of reactive crystallization were investigated.The optimal conditions were obtained as follows：back-feeding way was adopted during the reaction，addition of Na2CO3 was 110% of theoretical dosage，stirring rate was 400 r/min，reaction temperature was 80 ℃，concentration of LiCl was 3.2 mol/L.Results showed that stirring rate had slight influence on the yield；addition of Na2CO3，reaction temperature，and concentration of LiCl had affect on the yield；and reaction temperature and concentration of LiCl had an obvious influence.Feeding methods and PAA could change the morphology of Li2CO3；reaction temperature，stirring rate，concentration of LiCl， and PAA all could affect the purity of Li2CO3.