SOLVENT-EXTRACTION OF GALLIUM(III) AND INDIUM(III) WITH 1-(4-ETHYLPHENYL)-3-HYDROXY-4-PYRIDONES AND 1-(4-ETHYLPHENYL)-3-HYDROXY-2-METHYL-4-PYRIDONES

A new extracting agent, 1-(4-ethylphenyl)-3-hydroxy-4-pyridone (C2-HPP), was synthesized and used for the extraction of aluminum(III), gallium(III) and indium(III) into 1,2-dichloroethane. The acid dissociation constants, K-a, and the partition coefficient, K-D, of C2-HPP and the extraction constants, K-ex, of its metal complexes were determined. These results obtained were compared with those of 1-(4-ethylphenyl)-3-hydroxy-2-methyl-4-pyridone (C2-HMPP) reported already. The removal of a methyl group from the molecule of C2-HMPP was very effective for increasing the K-a values of C2-HPP and K-ex values of the metal complexes. The extracted species were ML(3) in all the extraction systems, where M denotes the metal ion.