Application Of Ionic Liquids In Separation And Enrichment Of Rare Earth

In this paper, bifunctional ionic liquid extractants (Bif-ILEs) tricaprylmethylammonium sec-octylphenoxy acetic acid ([A366][CA-12]) used for the Gd(III)、Nd(III)、Er(III)、Al(III) extraction in three acid systems have been investigated. Some conditions such as equilibrium aqueous phase acidity, extractant concentration, salting-out agent concentrations were discussed in the process of extraction. The results show that [A336][CA-12] can effectively separate Al(III) from rare earth elements in JiangXi ionic ores in sulfuric acid system. The best condition were the concentration of [A336][CA-12] was0.02mol/L, acidity of aqueous phase was about pH=2.9, phase ratio (Vo:Vw) was1:4, and the salt concentration was1mol/L. About82.6%of Al(III) was stripped by the three-stage cascade countercurrent extraction. In this process, the rare earth recovery rate was about85.2%.Simulation of the proportion of rare earth ions in dilute mineral liquid, The extraction capacity of0.5mol/L [A336][CA-12] on rare earth elements was11.5g/L, and the stripping capacity was110g/L. The results show that the average extraction of [A336][CA-12] on each rare earth ion in the JiangXi ionic ores can reach about90%.