Abstract
Using the liquid-liquid partition method, the formation of Co(II) complexes with 1-alkyl-2-methylimidazoles (where alkyl = C4H9 trough C12H25) at 25°C and at a fixed ionic strength of the aqueous phase (I = 0.5, (HL)NO3, KNO3) were studied. Dichloromethane, trichloromethane, and 2-ethylhexanol were used as diluents. The tetrahedral and octahedral complexes were formed. Stability constants (βn) of the complexes as well partition ratios (Pn) of the extracted species were determined. It was shown that both βn and Pn increased with an increasing 1-alkyl chain length. Tetrahedral complexes are more readily extractable by organic solvent. Their Pn values are the highest.