1994 Volume 43 Issue 1 Pages 61-66
A reliable procedure has been developed to separate nanogram platinum from hafnium, iron, alkali and alkaline-earth elements in dust samples for inductively coupled plasma mass spectrometry. The proposed procedure involves ashing at 700°C, decomposition in acid, separation and preconcentration of the analyte by anion exchangers. A rapid dissolution of the dust material was achieved by digestion in pressured vessels in a microwave oven, and subsequent evaporation on a hot-plate. The anionic form of platinum is adsorbed onto an anion-exchange column under acidic conditions in the 0.53 M HCl range. The interfering matrix ions and hafnium are not complexed, but pass through the column unretained. The platinum complex is then removed from the column with 40 ml of HNO3 at 90°C. The recovery was more than 60% for 10 ng of Pt, and the obtained column blank was 2.8±0.2 ng Pt. A stable isotope dilution method has been employed for the determination. The detection limit of the method, based on 1 g of dust sample, was 1.4 ng g-1 for Pt.
