Extraction of metal ions (Fe3+,Co2+,Ni2+,Cu2+ and Zn2+) using immobilized-polysiloxane iminobis(n-2-aminophenylacetamide) ligand system

A new insoluble solid functionalized ligand system bearing chelating ligand group of the general formula P-(CH2)(3)-N[CH2CONH(C6H4)NH2](2), where P represents [Si-O] (n) polysiloxane network, was prepared by the reaction of the immobilized diethyliminodiacetate polysiloxane ligand system, P-(CH2)(3)N(CH2CO2Et)(2) with 1,2-diaminobenzene in toluene. C-13 CP-MAS NMR, XPS and FTIR results showed that most ethylacetate groups (-COOEt) were converted into the amide groups (-N-C=O). The new functionalized ligand system exhibits high capacity for extraction and removal of the metal ions (Fe3+, Co2+, Ni2+, Cu2+ and Zn2+) with efficiency of 95-97% after recovery from its primary metal complexes. This functionalized ligand system formed 1:1 metal to ligand complexes.