Use of 2-hydroxy-3-methoxybenzaldehyde functionalized amberlite XAD-16 for preconcentration and determination of trace metal ions by flame atomic absorption spectrometry

In this work, a styrene-divinylbenzene based resin has been functionalized with 2-Hydroxy-3-methoxybenzaldehyde with the objective of employing it for the preconcentration of Zn(II), Cu(II), Ni(II), Cd(II), and Pb(II) contained in trace amount in various matrices. The optimum pH range for the maximum sorption of Zn(II), Cu(II), Ni(II), Cd(II), and Pb(II) was observed at pH 5.5-9.0, with the half-loading time, t_1/2, ranging from 5 to 13.7 min. The sorption of these metal ions in presence of potentially interfering matrices (including naturally occurring chelating agents) was investigated. The synthesized resin was able to preconcentrate metal ions at concentration as low as 5.55-8.33 μg L^-1, thereby resulting in the preconcentration factor in range of 240-360. The results favour the applicability of this method for the simultaneous preconcentration and determination of all the metal ions constituting complex matrices. The method has been successfully applied to the determination of the heavy metals in natural waters as well as food samples.