Chemical Model on the Synergistic Solvent Extraction of Manganese(II) from Chloride Solutions by a Mixture of Cyanex 272 and Cyanex 301

Abstract

Synergistic solvent extraction of manganese(II) using a mixture of Cyanex 272 and Cyanex 301 from chloride solutions has been studied in the view of developing a chemical model. Slope analysis method was used for the determination of extraction stoichiometry. The equilibrium constant for the synergistic solvent extraction reaction was calculated by taking into account of the complex formation reactions between Mn(II) and chloride ions. The activity coefficients of species in the aqueous phase were estimated by applying the Bromley equation. The calculated distribution ratios of Mn(II) agreed well with the experimentally measured values.

Estimation of the Equilibrium Constant for the Solvent Extraction of Mn(II) from Chloride Solutions by Cyanex 301

“…Hence, it is essential to examine the possibility of the formation of Mn(II) complexes with hydroxide and chloride ion in our experimental range. Complex formation between Mn and hydroxide ion can be ignored in our experimental range (Kumar et al, 2013b). Moreover, according to the distribution diagram of Mn(II) with the concentration of HCl, a small amount of MnCl + exists in our experimental range (Kumar et al, 2013b).…”

“…Complex formation between Mn and hydroxide ion can be ignored in our experimental range (Kumar et al, 2013b). Moreover, according to the distribution diagram of Mn(II) with the concentration of HCl, a small amount of MnCl + exists in our experimental range (Kumar et al, 2013b). Therefore, Mn 2+ and MnCl + were considered to exist as a stable species of Mn in our experimental range.…”

“…By applying the above method, the equilibrium constant for the solvent extraction of Mn by Cyanex 301 was estimated to be 3.1 × 10 -5 while using a mixture of Cyanex 272 and Cyanex 301 (Kumar et al, 2013b) in which the mole fraction of Cyanex 272 was kept at 0.6 was estimated to be 6.1 × 10 -2 .…”

“…The synergistic enhancement factor of 14 was obtained at the Caynex 272 mole fraction of 0.6. Moreover, the equilibrium constant for the synergistic solvent extraction of Mn(II) using a mixture of Cyanex 272 and Cyanex 301 from chloride solutions was estimated (Kumar et al, 2013b). Furthermore, literature survey reveals that there are no reports on the estimation of equilibrium constant for the solvent extraction of Mn(II) by Cyanex 301 from chloride solutions.…”