Separation of copper and zinc cations from each other in aqueous acid sulphate solution using Tri-N-Butyl phosphate (TBP)

The separation of copper and zinc cations from each other in aqueous acid sulphate solution using tri-n-butyl phosphate was investigated. The effects of the aqueous Zn2+ and Cu2+ concentrations, organic phase concentration of tri-n-butyl phosphate (TBP), pH and temperature on the degree of extraction of copper and zinc cations were studied. The loading of Copper and Zinc cations from the aqueous phase into the organic phase were pH dependent, a pH of 5 for copper (11) and pH 7 for Zinc (11) appeared to be most favourable. The respective increased concentrations of Cu2+, Zn2+ and TBP favored Cu2+ and Zn2+ extraction. Temperature had little effect. The experimental data suggested that, the separation of Cu2+ and Zn2+ from each other could be carried out by changing the pH at 32 ± 2°C. The separation of Cu2+ from Zn2+ is most favourable at pH 5, while Zn2+ from Cu2+ is most favourable at pH 7. The experimental results also indicate that this method of extraction could be employed to obtain up to 90% of each metal ion from the aqueous mixture.Keywords: extraction, aqueous phase Global Journal of Pure and Applied Sciences Vol. 12(1) 2006: 93-9