锰系吸附剂对碳酸盐型盐湖卤水中锂的吸附性能研究

Study on Adsorption Properties of Manganese Adsorbent for Lithium in Carbonate Salt Lake Brine

通过静态和动态吸附解吸实验,系统研究锰系吸附剂对碳酸盐型盐湖卤水中Li+吸附性能。结果表明,pH值升高有利于吸附过程,温度影响较小,吸附12 h后达到平衡吸附容量11.5 mg/g;锰吸附剂对Li+的吸附符合伪二级动力学模型和单分子层吸附的Langmuir等温吸附模型,且对Li+选择性很好,能有效地将Li+从卤水中分离吸收;以盐酸为解吸溶液,反应4 h解吸完全,盐酸浓度增加会造成锰溶损率升高,最高吸附剂溶损率达到1.47%;动态吸附收集2 BV~3 BV解吸液,锂浓度为1328 mg/L,此溶液可作合格液用于膜浓缩处理。

Static and dynamic adsorption and desorption experiments were carried out to study the adsorption performance of manganese adsorbent for Li+in carbonate salt lake brine.The results showed that the increase of pH value was beneficial for the static adsorption process,while the influence of temperature was not obvious.The equilibrium adsorption capacity reached 11.5 mg/g after 12 h.The adsorption of Li+by manganese adsorbent was in accordance with the pseudo-second-order kinetic model and the Langmuir isothermal adsorption model of monolayer adsorption.Manganese adsorbent has such good selectivity for Li+to separate and absorb Li+from brine.The desorption was complete after 4h with hydrochloric acid as desorption solution,while the increase of hydrochloric acid concentration resulted in the dissolution loss rate of manganese.The desorption solution of 2 BV~3 BV was collected of which the concentration of lithium reached 1328 mg/L.The solution could be used as qualified liquid for membrane concentration treatment.