Simultaneous Transport and Separation of Cu(II) and Zn(II) in Cu-Zn-Co Sulfate Solution by Double Strip Dispersion Hybrid Liquid Membrane (SDHLM)

Abstract

A double strip dispersion hybrid liquid membrane (SDHLM) was successfully used in the simultaneous extraction and separation of Cu(II), Zn(II), and Co(II) from Cu-Zn-Co dilute feed phase. In the double SDHLM system, Acorga M5640-loaded membrane was placed between the 1st and the 2nd compartment, whereas the mono(2-ethylhexyl) 2-ethylhexyl phosphonate [HEH(EHP)]-loaded membrane was placed between the 1st and the 3rd compartment of the transport cell. The feed solution was filled in the central feed compartment(1st compartment) of the transport cell. The effect of the different experimental variables on separation was examined. The optimum separation conditions were summarized.

An analysis of mass transfer resistances in the double SDHLM system shows that the mass transfer resistance for the diffusion of Zn(II) ions in the microporous membrane phase is dominant and the mass transfer resistances for the diffusion of copper (II) ions in the aqueous boundary layer and in the microporous membrane phase are dominant in comparison with the overall mass transfer resistance. The experiments verify that the double strip dispersion hybrid liquid membrane (SDHLM) possesses the nonequlibrium mass transfer characteristic.

Keywords:

• copper ions
• mass transfer resistance
• separation
• strip dispersion hybrid liquid membrane
• zinc ions

Notes

*Feed phase: 150 ml the feed solution of Cu²⁺, Zn²⁺, and Co²⁺, 0.167 M Na₂SO₄, the circulating flux of feed phase = 12600 ml/h.

For Cu(II), strip dispersion system: 100 mL organic solution containing 10% M5640 (w/v) and 20 mL 3 M HCl strip solution. The circulating flux of strip dispersion system = 780 ml/h.

For Zn(II), strip dispersion system: 110 mL organic solution containing 0.4 M dimer of HEH(EHP), 0.24 M dodecanol, and 10 mL 2 M H₂SO₄ strip solution. The circulating flux of strip dispersion system = 560 ml/h.

The accumulation of metal ion-carrier coordination compound in membrane is not listed in Table 1. But the calculation of the accumulation of metal ion-carrier coordination compound in membrane is as follows: For Cu(II) in Table 1: Accumulation (%) = figure in column of 5-figure in column of 12; For Zn(II) in Table 1: Accumulation (%) = figure in column of 5-figure in column of 10.

*Feed phase: 150 ml the feed solution of Cu²⁺, Zn²⁺, and Co²⁺, 0.167 M Na₂SO₄, pH = 2.0 the circulating flux of feed phase = 12600 ml/h.

For Cu(II), strip dispersion system: 100 mL organic solution containing 10% M5640 (w/v), and 20 mL 3 M HCl strip solution, the circulating flux of strip dispersion system = 780 ml/h.

For Zn(II), strip dispersion system: 110 mL organic solution containing 0.4 M dimer of HEH(EHP), 0.24 M dodecanol and 10 mL 2 M H₂SO₄ strip solution, the circulating flux of strip dispersion system = 560 ml/h.