Extraction - spectrophotometric determination of palladium with tetrabutylammonium iodide

A sensitive and selective extraction – spectrophotometric method for the determination of trace amounts of palladium is reported. The method is based on quantitative extraction of brownish tetrabutylammonium tetraiodopalladium (II) ion pair into a small volume of chloroform at pH 1.3-12.0, followed by spectrophotometric measurements. The Beer’s law is obeyed over the range 0.02-1.09mgml-1 at 445 nm with the molar absorptivity of 5.3×103 lmol-1cm-1. The Sandell’s sensitivity is 0.80 mg cm-2 for 0.001 absorbance unit. The method has a wide range and is simple, rapid and free from interferences from many cations and anions. The procedure was applied to the determination of palladium in the activated carbon.