Solvent Extraction of Copper Using TBP, D2EHPA and MIBK

Abstract

In this research, a synergetic system of solvent extraction process was developed to recover copper from aqueous solutions with tri-n-butyl phosphate (TBP), di-2-ethyl hexyl phosphoric acid (D2EHPA) and methyl iso-butyl ketone (MIBK). The effect of significant parameters such as pH, organic phase composition, aqueous to organic phase ratio (A : O), sodium acetate (CH₃COONa) concentration and presence of HCl were studied. The optimum mixing ratio of TBP: MIBK was found to to 7 : 3 for the copper extraction. In addition, the usage of HCl caused a reduction in the extraction percentage due to the instability of the TBP complex with copper in the presence of HCl. The A : O ratio of 1 : 1 resulted in a higher percentage of copper extraction. Finally, MIBK-TBP-D2EHPA-acetate system could extract more than 99% of copper under the optimum condition.