(中南大學 冶金與環(huán)境學院，長沙 410083)
摘 要: 針對高鎂鋰比鹽湖中鋰難以提取的難題，一種通過活性鋁水解吸附鋰的方法被用于從高鎂鋰比鹽湖鹵水結(jié)晶產(chǎn)物中高效提取鋰。考察氯化鉀、氯化鈉和氯化鋰及其混合物對鋁的活化效果，進而對從NaCl和LiCl混合鹽中提取鋰進行研究，然后研究MgCl2和LiCl混合鹽活化金屬Al及水體分解Mg和Li，考察機械活化及活化鋁水解反應條件對鎂鋰分離的影響。結(jié)果表明：含有LiCl的鹽能使金屬鋁完全能被活化，經(jīng)活化后鋁快速與水反應生成活性氫氧化鋁，同時吸附其中的鋰。通過控制合適的機械活化和水浸出條件，活性鋁水解吸附法能有效從混合鹽中提取鋰，鋰的吸附率能達到96%。當在鎂鋰質(zhì)量比為20:1的混合鹽中加入6%的鋁，機械活化時間60min后，采用50 ℃的水浸出活化后的物料2.0 h，鋰的吸附率達到85%，而鎂的吸附率僅約為0.6%，所得吸附沉淀中的鎂鋰質(zhì)量比降低到0.12。因此，采用含鎂鋰的混合鹽直接活化鋁然后水解能實現(xiàn)很好的鎂鋰分離。
關(guān)鍵字: 鋰；鋁；鎂；水浸；吸附；機械活化
（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
