Highly selective liquid-liquid extraction from sulfuric acid medium and spectrophotometric determination of palladium(II) with alpha-benzilmonoxime

A selective method for the extraction and spectrophotometric determination of palladium with alpha-benzilmonoxime (BZ) is described. BZ-Pd(II) complex was extracted from acidic aqueous solution (1.5 M sulfuric acid) into a ch loroform layer. Absorbance was measured at 434 nm and molar absorptivity wa s found to be about 1.0 x 10(4) cm(-1) mol(-1) liter(-1). Beer's law is obe yed over the range 0.300 to 13.00 mu g ml(-1)with a limit of detection of 0 .066 mu g ml(-1) Pd(II). The effects of BZ concentration in chloroform, sul furic acid concentration, and shaking time were studied. Effects of interfe rence by a number of metal ions was investigated. The method is fast, accur ate, selective, and precise. This method has successfully been applied to t he determination of palladium in synthetic mixtures and in the laboratory p alladium-carbon powder. (C) 1999 Academic Press.