Column preconcentration of palladium using protocatechuic acid and tetradecyldimethylbenzylammonium- iodide-naphthalene as an adsorbent

Abstract

A preconcentration procedure has been established for the determination of' trace amounts of pallaldium with a solid ion-pair of tetradecyldimethylbenzylamrnonium (TDBA) and iodide on microcrystalline naphthalene using a simple funnel-tipped glass tube as the preconcentration column. Palladium reacts with protocatechuic acid to form a water-soluble coloured complex anion. The complex anion forms a water-insoluble palladium- protocatechuic acid-TDBA complex on naphthalene packed in a column. Palladium is quantitatively retained on the naphthalene in the <em>p</em>H range 4.0-7.0 and at a flow rate of 2 ml/min The solid mass consisting of palladium complex and naphthalene is washed from the column with 5 ml of dimethylformamide (DMF) and trace amounts of palladium measured by atomic absorption spectrometry at 244.8nm. The detection limit is 0.0257 µg/ml. The developed method has been tested for the determination of palladium in synthetic as well as actual samples.