Liquid-Liquid Extraction of Ir, Ru, and Rh from Chloride Solutions and Their Separation Using Different Commercially Available Solvent Extraction Reagents

Abstract The extraction of Ir, Ru, and Rh from their chloride solutions was carried out using different commercially available solvent extraction reagents. The extractants studied were Alamine 300, Alamine 336, Aliquat 336, Cyanex 921, Cyanex 923, Cyanex 471, Cyanex 272, LIX 54, LIX 860N‐I and tributyl phosphate (TBP). The distribution coefficients for the metals were determined under different concentrations of Cl− and H+ ions in the aqueous phase. The extraction data relating to the consecutive steps of stripping the metal species from the loaded organic phase were also recorded. The results showed that more than 90% of the Ir can be extracted using Alamine 300, Alamine 336, and Aliquat 336 when less than 0.2 M Cl− is present in the aqueous phase, and that quantitative stripping of Ir can be performed. For higher concentrations of Cl− in the aqueous phase, Cyanex 921 was found to be the best extractant for Ir, although the mixed extractants such as Alamine 336+LIX 54, Aliquat 336+LIX 54, and Cyanex 921+...