Selective flotation-spectrophotometric procedure for the trace analysis ofpalladium(II) in different matrices

2-Hydroxyimino-3-(2-hydrazonopyridyl)-butane (HHB) was investigated as a ne w reagent for the flotation of palladium(II). The metal ion forms a 1:1 pal e-violet complex with HHB in aqueous solution. An intense clear violet laye r was formed, after flotation, by adding an oleic acid (HOL) surfactant. Th e composition of the float is 1:1 (Pd:HHB). A highly selective and sensitiv e spectrophotometric procedure was proposed for the determination of microa mounts of Pd(II) as its floated complex. The flotation-determination method was achieved in the pH range 2.5-7.0. Beer's law was obeyed up to 6 x 10(- 5) mol l(-1) (6.3 ppm). Interference from various foreign ions was avoided by adding excess HHB. The molar absorptivities of Pd-HHB and Pd-HHB-HOL sys tems are 2.5 x 10(3) and 2.1 x 10(4) l mol(-1) cm(-1) at 555 nm, each. The formation constants of the species formed in the presence and absence of HO L are 9 x 10(5) and 4.6 x 10(7) l mol(-1), respectively. The method was suc cessfully applied to the analysis of Pd(II) in simulated ores, complexes, a nd water samples. The separation mechanism is discussed.