Simple and Simultaneous Method for Determination of Palladium(II) and Ruthenium(III) using Second-Order-Derivative Spectrophotometry

Abstract

A simple, sensitive, and selective second-order-derivative spectrophotometric method has been developed for the simultaneous determination of palladium(II) and ruthenium(III) using 2-hydroxy-3-methoxy benzaldehyde thiosemicarbazone (HMBATSC) as a chromophoric reagent. The reagent (HMBATSC) reacts with Pd(II) and Ru(III) at pH 3.0, forming soluble yellowish green and dark brown species, respectively. Palladium and ruthenium present in the mixture were simultaneously determined without solving the simultaneous equations by measuring the second derivative amplitudes at 445 nm and 385 nm, respectively. Further, the Beer's law was obeyed in the range 0.21–12.78 µg mL−1 and 0.25–13.42 µg mL−1 for Pd(II) and Ru(III), respectively. A large number of foreign ions did not interfere in the present method. The proposed method was successfully applied for the determination of palladium in hydrogenation catalysts and ruthenium in water samples.