Study of Zn (II) extraction by 5-azidomethyl-8-hydroxyquinoline: Experiment and modelling

The extraction of Zn (II) by 5-azidomethyl-8-hydroxyquinoline (HZQ) has been studied. A modified Debye–Hückel equation was used for modeling of system Zn(II)/HZQ/HCl/Chloroform in various conditions of use. The distribution ratio of HZQ and of Zn (II) in organic and aqueous phases has been treated. log10 (PHZQ) = 2.91 is obtained for HZQ coefficient of partition and log10(kHZQ) = 4.23 for constant of chemical equilibrium HZQ + H3O+ ⇌H2(ZQ)+ + H2O. From quantitative evaluation of the extraction equilibrium data of Zn (II), it has been deduced that the predominant complex extracted is Zn(ZQ). The extraction constant of Zn (ZQ)2 has a value of log10 (k1200) =0.077. The calculated results are compared to the experimental data.