THE ANALYSIS OF HIGH-PURITY NOBLE-METALS AND THEIR SALTS BY ICP-MS

Ongoing work is being carried out at Mintek to establish methods for t he determination of trace levels of impurities in high-purity noble me tals and their salts. The sample-preparation methods are outlined, and the optimum instrumental parameters that were established are tabulat ed. Spectral interferences arising from the presence of a matrix eleme nt at high concentration levels, including abundance sensitivity overl ap and the formation of noble-matrix oxides, are discussed. Accuracy w as established by the comparison of the results with those obtained by a DC-arc method, and by spike recovery tests. The precision of measur ement was found to vary from 0.72 to 49% S(r) for conentrations of bet ween 15 and 0.5 mug/g, respectively.