盐湖卤水制备电池级碳酸锂工艺影响因素研究

Process for preparing battery-grade lithium carbonate from salt lake brineResearch on influencing factors

以盐湖卤水氯化锂溶液与碳酸钠溶液反应结晶制备电池级碳酸锂,由于反应条件、杂质离子、搅拌速度等的影响,生产出的碳酸锂品质不符合行业标准。通过对反应条件中高锂液的锂钠摩尔比、反应温度、搅拌速度、杂志离子等的影响研究,得出复杂盐湖卤水体系制备电池级碳酸锂工艺的最佳控制条件,即Li+/Na+物质的量比约为5.5,反应温度为70℃,搅拌速度为400r/min,碳酸钠摩尔浓度为2.45mol/L,主要杂质离子B含量小于10mg/L,加料方式为碳酸钠溶液加入到氯化锂盐水体系当中,从而得到的碳酸锂纯度≥99.5%,符合电池级碳酸锂标准。

Battery-grade lithium carbonate is prepared by reacting and crystallization of salt lake brine lithium chloride solution and sodium carbonate solution.Due to the influence of reaction conditions,impurity ions and stirring speed,the quality of lithium carbonate produced does not meet industry standards.In this paper,the optimal control conditions for the preparation of battery-grade lithium carbonate in complex salt lake brine system,that is,Li+/Na+mole,are obtained by studying the effects of the lithium-sodium molar ratio of the high-liquid liquid,reaction temperature,stirring speed,and magazine ions in the reaction conditions.The ratio is about 5.5,the reaction temperature is 70℃,the stirring speed is 400 r/min,the molar concentration of sodium carbonate is 2.45 mol/L,the content of the main impurity ion B is less than 10 mg/L,the feeding method is sodium carbonate solution added to lithium chloride brine In the system,the purity of lithium carbonate obtained is≥99.5%,which meets the battery-grade lithium carbonate standard.