Atomic Absorption Determination of Lead, Bismuth, Selenium, Tellurium, Thallium and Tin in Complex Alloys Using Direct Atomization from Metal Chips in the Graphite Furnace

Abstract

Atomic absorption spectrometry utilizing electrothermal atomization devices has proven to be the best technique available for the analysis of complex alloys for trace elements of metallurgical interest. The determination of lead, bismuth, selenium, tellurium, thallium, and tin was successfully demonstrated by direct atomization from complex, nickel-base alloy chips with commercial atomic absorption furnace equipment. The determination was carried out by first milling metal chips from the bulk sample. The sample was transferred directly to the furnace and atomized immediately with no preatomization heating cycle. A series of cast alloy standards containing the trace elements were prepared by additions to a nickel-base alloy, then subsequently analyzed by established analytical methods. Of the three commercial atomizers studied, the Perkin-Elmer model HGA 2100 proved to be the most suitable for direct determination of the trace elements of interest. The coefficient of variation of absorbance measurements varied from 7% for bismuth which is easily atomized to 25% for tin which is more difficult to atomize.