(中南大学 冶金与环境学院，长沙 410083)
摘 要: 针对高镁锂比盐湖中锂难以提取的难题，一种通过活性铝水解吸附锂的方法被用于从高镁锂比盐湖卤水结晶产物中高效提取锂。考察氯化钾、氯化钠和氯化锂及其混合物对铝的活化效果，进而对从NaCl和LiCl混合盐中提取锂进行研究，然后研究MgCl2和LiCl混合盐活化金属Al及水体分解Mg和Li，考察机械活化及活化铝水解反应条件对镁锂分离的影响。结果表明：含有LiCl的盐能使金属铝完全能被活化，经活化后铝快速与水反应生成活性氢氧化铝，同时吸附其中的锂。通过控制合适的机械活化和水浸出条件，活性铝水解吸附法能有效从混合盐中提取锂，锂的吸附率能达到96%。当在镁锂质量比为20:1的混合盐中加入6%的铝，机械活化时间60min后，采用50 ℃的水浸出活化后的物料2.0 h，锂的吸附率达到85%，而镁的吸附率仅约为0.6%，所得吸附沉淀中的镁锂质量比降低到0.12。因此，采用含镁锂的混合盐直接活化铝然后水解能实现很好的镁锂分离。
关键字: 锂；铝；镁；水浸；吸附；机械活化
（School of Metallurgy and Environment, Central South University, Changsha 410083, China）
Abstract:In order to extract lithium from salt lake with high mass ratio of Mg to Li efficiently, the hydrolysis-adsorption method of activated aluminum was developed to extract Li from the crystallized product of salt lake brine with high mass ratio of Mg to Li. The mechanical activation effect of Al by adding KCl, NaCl and LiCl mixture was investigated. And the extraction of Li from the NaCl-LiCl mixed salt was also researched. The effect of mechanical activation and water leaching reaction on the Li adsorption was investigated. The mixed salt containing MgCl2 and LiCl was used to activate Al and the separation of Mg and Li was also researched. The parameters effects of mechanical activation and Al hydrolysis on separation of Mg and Li were investigated. The results show that Al can be activated completely, and the activated Al can react with water to produce activated Al(OH)3 rapidly. Through controlling appropriate parameter for mechanical activation and water leaching, Li can be extracted from NaCl-LiCl mixed salt by hydrolysis-adsorption of activated Al, and Li adsorption can reach 96%. When 6% Al is added into the mixed salt with Mg and Li mass ratio of 20:1 and activating time of 60min, and then the activated Al is leached at 50 ℃ for 2.0 h, the Li adsorption reaches 85% and Mg adsorption is only about 0.6%, and the Mg and Li mass ratio in adsorption precipitation decreases to 0.12. The above research results indicate that mixed salt containing Mg and Li can effectively activate Al and then achieve the separation of Mg and Li.
Key words: lithium; aluminum; magnesium; water leaching; adsorption; mechanical activation
