Preconcentration and separation of trace metal ions using silica gel modified with 2-(5-bromo-pyridylazo)-5-diethylaminophenol

Absorption behevior of the transition metal ions on the silica gel modified with 2-(5-Bromo-Pyridylazo)-5-Diethylaminophenol (5-Br-PADAP-SG) is studied by bath experiment. The maximum absorption capacity of Cu(II), Zn(II), Ni(II), Cd(II), Co(II), Fe(II) on 5-Br-PADAP-SG is 17.7, 24.0, 15.8, 16.4, 10.2, 13.8??mol/g respectively. At pH 5.8, Cu(II), Ni(II), Cd(II), Mn(II), Fe(III) are simutaneously analysed after preconcentration through 5-Br-PADAP-SG column. At pH 3.0, Cu(II), Ni(II) and Cd(II), Mn(II) can be separated from each other from the mixed solution. The metal ions of ppb level in water samples can be measured by atomic absorption spectroscopy.EI03214-218