4-Phenylenediaminepropylsilica xerogel as a sorbent for copper determination in waters by slurry-sampling ETAAS

Abstract

The synthesis of a new, hybrid mesoporous sorbent, 4-phenylenediaminepropylsilica (4-PhAP/silica xerogel) obtained by the sol–gel process is described. This material was characterized by infrared spectroscopy (IR), elemental analysis (CHN), and nitrogen adsorption–desorption isotherms. Subsequently, this material was employed for the successful pre-concentration of copper in natural water reference materials. The copper characteristic mass was 15.0 ± 0.2 pg. The detection limit for copper determination in natural waters employing the pre-concentration procedure was 0.2 µg l⁻¹. The average tube lifetime was 750 analytical firings when 20 µl of 1.5% m/v copper sorbed on 4-PhAP/silica xerogel slurry was delivered to a previously treated W–Rh treated platform of a transversely heated graphite atomizer (TGA). The pre-concentration factor obtained with 4-PhAP/silica xerogel as adsorbent for copper determination was 3.75 and the retention capacity of the sorbent was 0.52 mmol copper per gram of sorbent.