Separation Science and Technology, Vol.49, No.2, 290-297, 2014
Liquid-Liquid Extraction and Separation of Divalent Manganese and Zinc by Na-CYANEX 272 from Sulfate Solution
Extraction and separation of divalent Mn and Zn ions from acidic sulfate solutions containing 0.05M of each metal ion have been carried out using 0.04M Na-CYANEX 272 in kerosene. The influences of the following parameters were studied: shaking time, equilibrium pH, extractant concentration, diluents type, and temperature. The extraction percentage of both metal ions increased with increasing equilibrium pH in the range 2.0-4.0 and 2.75-6.0 for Zn(II) and Mn(II), respectively. The separation factor, S-(Zn/Mn), increases with the increase in pH to reach a maximum value of about 24x10(3) at pH 4.0. Extraction of both metal ions increased with increasing extractant concentration. Aliphatic diluents were preferred compared to aromatic diluents. The thermodynamic parameters (H, S, and G) for Mn(II) and Zn(II) were calculated. The extraction mechanism of both metals by Na-CYANEX 272, stripping from loaded extractant and recycling of extractant used in the extraction process were also investigated.