Extraction-spectrophotometric determination of palladium(II) with thiazole-2-carbaldehyde 2-quinolylhydrazone

Abstract

Thiazole-2-carbaldehyde 2-quinolylhydrazone (TAQH) was prepared as a reagent specifically for the spectrophotometric determination of trace amounts of palladium(II) following an extraction process. In the presence of chloride ions, palladium(II) reacts with TAQH in the wide acidity range to form a 1:1 metal to ligand complex extractable into benzene. The extracted species has absorption maxima at 588 and 625 nm with a molar absorptivity of 1.93 × 10⁴ l mol^–1 cm^–1 at the latter wavelength and obeyed Beer's law over the range 0–4.2 µg ml^–1 of palladium at 625 nm. The method is reasonably selective and sensitive for palladium(II) and was satisfactorily applied to the determination of palladium in some palladium catalysts.