Complexometric determination of palladium (II) using hydroxylamine hydrochloride as releasing agent

Abstract

A method is proposed for selective complexometric determination of Pd(II) using hydroxylamine hydrochloride as a replacing (masking) agent. An excess of EDTA is added to Pd(II) solution containing associated diverse metal ions and the uncomplexed EDTA is titrated at pH 5-6 (acetic acid - acetate buffer) with lead nitrate solution using xylenol orange as indicator. Hydroxylamine hydrochloride is then added to displace EDTA from the Pd-EDTA complex. The released EDTA is titrated with standard lead nitrate solution. Reproducible and accurate results are obtained in the concentration range 0.3-15 mg of Pd with a relative error of 0.4% and coefficient of variation (n=6) not exceeding 0.4%.