A selective reagent for the spectrophotometric determination of palladium

Abstract

A spectrophotometric method for the determination of trace amounts of palladium(II) with ethyl 3-phenyl-5-isoxazolone-4-carboxylate was developed. With this reagent, palladium forms a yellow complex, stable in the pH range 1–6.5, which is extractable into 4-methylpentan-2-ol from 0.05–4 M perchloric acid medium. The coloured complex adheres to Beer's law at 370 nm in aqueous and in 4-methylpentan-2-ol solutions, with molar absorptivities of 3.5 × 10³ and 3.9 × 10³ l mol^–1 cm^–1, respectively. Other platinum-group metals do not interfere. In the presence of highly coloured ions, extraction with 4-methylpentan-2-ol eliminates all interferences. Cyanide ions interfere in the method.