Determination of gold in the presence of platinum and palladium by electrothermal atomisation atomic absorption spectrometry

Abstract

Traces amounts of gold in the presence of an excess of platinum and palladium have been determined by atomic absorption spectrometry with electrothermal atomisation using different ETA-AAS systems. Detection limits for the furnace atomisers used were evaluated: SP9 2.4 × 10^–11 g, HGA-74 1.6 × 10^–10 g and GRM-1268 1.4 × 10^–10 g. To reduce metal matrix interferences on the atomic absorption signal of gold modification of the graphite tube, sample preparation and separation of analyte from the matrix by an ion-exchange method were investigated. The best results were obtained, as far as precision is concerned, when ion-exchange separation prior to an atomic absorption determination of gold was used. The proposed method for the determination of gold was adopted for its determination in platinum powder and platinum chloride.