预浓缩强化江汉盆地卤水吸附提锂的研究

为提高卤水吸附提锂效率，开发了预浓缩-吸附法提锂工艺。基于50℃、100℃下Na⁺、K⁺//Cl^--H₂O三元体系相图理论指导，研究了不同蒸发温度条件下卤水中锂的浓度及锂折损率随蒸发率的变化关系，对比了吸附剂对预浓缩前后卤水的吸附效果。结果表明，蒸发过程中溶液中锂浓度和锂折损率不受蒸发温度的影响；蒸发率超过40%后，卤水中锂折损率快速上升；以锰系吸附剂吸附蒸发率40%、锂浓度55 mg/L的预浓缩卤水中的锂，4 h后吸附容量达4.25 mg/g,高于吸附剂对原卤的吸附容量(3.39 mg/g),证实卤水预浓缩处理可以强化吸附提锂效果。

Pre-concentration to Enhance Lithium Extraction by Brine Adsorption in Jianghan Basin

In order to improve the efficiency of lithium extraction by brine adsorption, a process consisting of pre-concentration and adsorption was developed for lithium extraction. Based on the theory of phase diagram of Na⁺, K⁺∥Cl^--H₂O ternary system at 50 ℃ and 100 ℃, variation of lithium concentration and lithium loss rate in brine at different temperatures with different evaporation rate was explored in the test, and the adsorption effects of adsorbents on brine before and after pre-concentration were compared. The results show that the concentration and loss rate of lithium in the solution are not affected by evaporation temperature. As the evaporation rate exceeded 40%, the loss rate of lithium in brine increased rapidly. The pre-concentrated brine with concentration of 55 mg/L lithium at an evaporation rate of 40% was adsorbed with manganese absorbent, showing that the lithium adsorption capacity reached 4.25 mg/g after 4 hours, higher than the adsorption capacity of 3.39 mg/g in the original brine without pre-concentration. It is proven that brine pre-concentration can enhance the adsorption effect of lithium brine extraction.