Solvent extraction and spectrophotometric determination of Sb(lll) with pyridine-2-acetaldehyde salicyloylhydrazone

Abstract

An extractive spectrophotometric method is described for the determination of antimony(III) using pyridine-2-acetaldehyde salicyloylhydrazone (PASH) as reagent. Effect of variation in acidity, reagent concentration, equilibration time, etc have been studied. Sb(III) is extracted quantitatively from 1.25 mol dm^-3 hydrochloric acid. The yellow coloured I: I (metal: ligand) complex in chloroform absorbs maximally at 405 nm. Beer's law is obeyed over the concentration range of 1.5- 5.0 mg ml^-1 of Sb(III). The molar absorptivity and Sandell's sensitivity are found to be 1.94 x 10⁴l mol^-1 cm^-1 and 6.02 ng cm^-2 respectively. The method is precise and simple and has been applied for the determination of Sb(III) in synthetic mixtures alloys and a pharmaceutical sample.