Selective transport of copper across a bulk liquid membrane using 8-hydroxy quinoline as carrier

The carrier activity of 8-hydroxy quinoline (oxine) towards the facilitated transport of copper ions through chloroform bulk liquid membrane has been studied. The effects of pH of the source phase, the nature of stripping agents in the receiving phase, presence of other cations, nature of synergistic reagents on the transport were investigated. A solution of 0.1 M nitric acid (HNO3) served as receiving phase for maximum transport of the metal ion. Addition of 2-amino pyridine to the membrane phase had a synergistic effect and caused a pronounced enhancement in the transport, while citric acid or glycine did not change the transport significantly. Maximum transport efficiency was observed for Cu2+ ion when it was present in the concentration of 10−4 M. Tolerance to the presence of Pb2+, Zn2+, Cd2+, Ni2+, Fe2+ and Fe3+ ions was investigated and it was found that Cu2+ transport was not affected even in the presence of 10-fold concentration of these ions. This system was applied for the recovery of copper in electroplating industrial waste water samples.