An extraction chromatographic solid porous polysiloxane
functionalized by chelating diethylenetriamine ligand of the general
formula P-(CH2
)3
-NH(CH2
)2NH(CH2
)2NH2
, (Where P represents [Si-O]n
siloxane network) has been evaluated for the separation of Co(II), Ni(II)
and Cu(II) from aqueous solutions. The chromatographic parameters of the
separation method have been optimized. The ligand system retained Co(II),
Cu(II) and Zn(II) effectively when used as a metal ion extractant by
controlling the pH value. The ligand system also shows a good separation
of a mixture of metal ions Co(II), Ni(II) and Cu(II) when used as
chromatographic stationary phase. The optimum separation pH values were
4.5, 4 for Co(II) and Ni(II) respectively, while a solution of 0.1 M HNO3
was used to elute Cu(II). Metal ions were also preconcentrated at pH 5.5.
The chemisorbed metal ions were regenerated from the solid extractant
using 0.5 M HCl.