Solvent Extraction Equilibria of FeCl_3 with Alamine336 Salt

摘要

Solvent extraction experiments of FeCl_3 with Alamine336 salt were performed. It was found from the loading capacity of Alamine336 salt that the solvent extraction reaction depended on the ratio of initial concentration of Alamine336 to FeCl_3. When the concentration of Alamine336 was in excess compared to that of FeCl_3, Alamine336 participated in the extraction reaction as a dimer. When the initial concentration ratio of Alamine336 to FeCl_3 was below three, ferric chloride was extracted by monomeric Alamine336. The equilibrium constants of solvent extraction, K_(ex) = 2.22 X 10~4 and K_(ex) = 6.41 X 10~5 for monomeric and dimeric Alamine336 respectively, were determined from extraction data by considering activity coefficient of solutes in the aqueous phase. The predicted distribution coefficients of iron agreed well with those experimentally measured.