Beata Pospiech

Synergistic Solvent Extraction and Transport of Zn(II) and Cu(II) across Polymer Inclusion Membranes with a Mixture of TOPO and Aliquat 336

Separation of zinc(II) and copper(II) ions from aqueous solutions by synergistic extraction and transport through polymer inclusion membranes (PIMs) has been investigated. A mixture of trioctylphosphine oxide (TOPO) and trioctymethylammonium chloride (Aliquat 336) was used as a selective extractant as well as an ion carrier in polymer membranes. The effects of hydrochloric acid concentration in the aqueous phase and extractants concentration in the organic phase on the separation process of zinc(II) and copper(II) ions have been studied. Zn(II) ions were successfully separated from Cu(II) ions in solvent extraction process using 0.025 M TOPO and 0.06 M Aliquat 336 in kerosene. Polymer inclusion membranes (PIMs) containing a mixture of TOPO and Aliquat 336 as the ion carrier have been prepared and the facilitated transport of Zn(II) and Cu(II) ions has been studied. The influence of membrane composition on the transport kinetic of Zn(II) and Cu(II) has been evaluated. Zn(II) ions were preferably transported from the aqueous solutions containing Cu(II) and above 87% of Zn(II) ions were effectively recovered from the 0.5 M HCl solution as the source phase through PIM into 0.5 M H2SO4 as the stripping phase.

Highly Selective Solvent Extraction of Zn(II) and Cu(II) from Acidic Aqueous Chloride Solutions with Mixture of Cyanex 272 and Aliquat 336

Selective solvent extraction of zinc(II) and copper(II) from aqueous acidic chloride solutions by mixture of bis(2,2,4-trimethylpentyl)phosphinic acid (Cyanex 272) and trioctymethylammonium chloride (Aliquat 336) in kerosene has been investigated. Detailed studies have been conducted by varying pH, hydrochloric acid, and chloride concentrations in aqueous phase as well as extractants concentration in organic phase. A full and high selective solvent extraction of zinc(II) over copper(II) from acidic chloride solutions has been achieved by 0.1 M Cyanex 272 and 0.06 M Aliquat 336 in kerosene while efficient Zn(II) stripping has been performed by using 1 M sulphuric acid. The following selectivity coefficients of zinc(II) over Cu(II) (SZn/Cu) during their solvent extraction from 1 M NaCl at pH 0.5 by Cyanex 272, Aliquat 336, and their mixture were found to be equal to: 1.7, 62, and 3162, respectively.