Amberlite XAD-2 functionalized with o-aminophenol: synthesis and applications as extractant for copper(II), cobalt(II), cadmium(II), nickel(II), zinc(II) and lead(II) (original) (raw)

A stable chelating resin matrix was synthesized by covalently linking o-aminophenol (o-AP) with the benzene ring of the polystyrene-divinylbenzene resin, Amberlite XAD-2, through a -N N -group. Elemental analyses, thermogravimetric analysis (TGA) and infrared spectra have characterized the resulting chelating resin. It has been used to preconcentrate Cu 2 + , Cd 2 + , Co 2 + , Ni 2 + , Zn 2 + and Pb 2 + , prior to their determination by flame atomic absorption spectrometry. The optimum pH values for quantitative sorption of Cu, Cd, Co, Ni, Zn and Pb are 6.2-7.4, 5.6-7.2, 5.6-9.0, 6.0-9.0, 5.7-7.0 and 5.0 -6.0, respectively. These metals are desorbed (recovery 91 -98%) with 4 mol dm − 3 HNO 3 . The sorption capacity of the resin is 3.37, 3.42, 3.29, 3.24, 2.94 and 3.32 mg of metal g − 1 of resin, respectively, for Cu, Cd, Co, Ni, Zn and Pb. The effect of NaF, NaCl, NaNO 3 , Na 2 SO 4 , and Na 3 PO 4 on the sorption of these metal ions has been investigated. These electrolytes are tolerable up to 0.01 mol dm − 3 in case of all the metal ions, except Cl − which is tolerable even up to 0.1 mol dm − 3 for Zn and 1.0 mol dm − 3 for Pb. The preconcentration factor for Cu, Cd, Co, Ni, Zn and Pb are 50, 50, 100, 65, 40 and 40 (concentration level 10 -25 mg dm − 3 ) respectively. Simultaneous enrichment of the six metals is possible. The method has been applied to determine Cu, Cd, Co, Ni, Zn and Pb content in well water samples (RSD 58%).