Application of Oxazolone Azo Dye Modified Alumina as New Sorbent for Separation of Palladium from Anodic Slime and Wastewater Samples

Abstract

In the present work, a new kind of alumina-based adsorbent with high selectivity and stability and efficient adsorption was prepared. Alumina was coated with an oxazolone azo dye, 2-(4-{2-[4-(dimethylamino) phenyl]-1-diazenyl}phenyl)-4-[1-phenyl methylidene]-5(4H)-oxazolone, and then used for preconcentration of trace amounts of palladium. The analytical procedure involved the complex formation of Pd with oxazolone azo dye as a chelating agent in buffer media of pH 5. The stability of sorbent was excellent and adsorption capacity did not change significantly after 100 consecutive uses of 50.0 mg of modified alumina. Under the optimum conditions, the preconcentration factor of the method was 150. The linearity was maintained in the concentration range of 0.33 ng mL^-1to 8.0 mg mL^-1 in the original solution. For 2.0 µg mL^-1 of Pd, the relative standard deviation 1.4% and detection limit 0.25 ng mL^-1was obtained. The proposed method was successfully applied to the determination of trace amounts of palladium in the anodic slime and wastewater samples.