Staff chemist, Handy & Harman, Fairfield, Conn.
Pages: 15 Published: Jan 1981
A d-c plasma emission spectrometer was used to measure 20 trace metal impurities in palladium grade 99.95 percent or better. The samples were analyzed using matched matrix standards and aqueous standards with and without a lithium buffer.
The use of high-purity matrix standards indicated whether the amounts tested for in the sample were above or below the matrix level, but the contents of the matrix had to be added in order to establish the absolute impurity level. The contents of the matrix were ascertained using a standard additions approach. Because the palladium matrix exerted an ionization enhancement on each of the 20 trace analytes, using aqueous standards gave erroneously high impurity level readings. Adding a lithium buffer to both the palladium sample and the aqueous standards compensated for the enhancement and gave more correct readings.
palladium, palladium impurities, d-c plasma, enhancements, standard additions, lithium buffer, metals, analytical techniques, trace constituents
Paper ID: STP28098S