Extraction and spectrophotometric determination of trace amount of Pd(II) with 2,2 '-dithiodianiline

A method for the extraction-spectrophotometric determination of palladium w ith 2,2'-dithiodianilline (DTDA) is described. DTDA-Pd(II) complex is extra cted from an aqueous solution with pH 3 into isobutyl methyl ketone (IBMK) layer. The absorbance is measured at 397 nm and the molar absorptivity foun d to be 1.47 x 10(6) 1 mol(-1) cm(-1). The complex system conforms to Beer' s law over the range 0.3-220 ng ml(-1) palladium (II). The effect of pH (1- 6), NaClO4 concentration, DTDA concentration and shaking time were studied. The ratio of the metal ion to ligand molecules in the complex and its stab ility constant were found to be 1:1 and 1.45 x 10(6), respectively. The tol erance limit for many cations and anions have been determined. Finally the method has been applied successfully to the determination of palladium in s ynthetic mixtures, alloy and catalyst samples. (C) 2000 Elsevier Science B. V. All rights reserved.