Determination of trace amounts of copper, nickel and zinc in palladium compounds by solvent extraction flame atomic absorption spectrometry

Abstract

A method is described for the determination of trace amounts of Cu, Ni and Zn in diamminedichloropalladium and diamminedinitropalladium by flame atomic absorption spectrometry after an extraction procedure using ammonium pyrrolidin-1-yldithioformate [ammonium pyrrolidinedithiocarbamate (APDC)] as complexing agent and isobutyl methyl ketone (IBMK) as extractant. Another extraction system, NH₄SCN–IBMK, was used for the preliminary removal of Pd which also forms extractable complexes with APDC. Optimum conditions for the selective separation of Pd and for the simultaneous extraction of Cu–, Ni– and Zn–PDC complexes into IBMK were determined. The sensitivity and precision of the proposed method are sufficient for quality control requirements.