INTERFERENCE MECHANISMS OF SODIUM-CHLORIDE ON ZINC AND COBALT IN GRAPHITE-FURNACE ATOMIC-ABSORPTION SPECTROMETRY USING A DUAL CAVITY PLATFORM

Authors
Citation
S. Akman et G. Doner, INTERFERENCE MECHANISMS OF SODIUM-CHLORIDE ON ZINC AND COBALT IN GRAPHITE-FURNACE ATOMIC-ABSORPTION SPECTROMETRY USING A DUAL CAVITY PLATFORM, Spectrochimica acta, Part B: Atomic spectroscopy, 49(7), 1994, pp. 665-675
Citations number
32
Categorie Soggetti
Spectroscopy
ISSN journal
05848547
Volume
49
Issue
7
Year of publication
1994
Pages
665 - 675
Database
ISI
SICI code
0584-8547(1994)49:7<665:IMOSOZ>2.0.ZU;2-#
Abstract
The interferences of sodium chloride with the determination of a volat ile (zinc) and a low volatility (cobalt) element by graphite furnace a tomic absorption spectrometry (GFAAS) were examined. For various masse s of the sodium chloride, the effects of pretreatment temperature and time, and heating rate on the atomization of the analyte were investig ated using a specially designed dual cavity platform, which in princip le allows the analyte and the interferent to vaporize from the separat e cavities so that gas and condensed phase interferences can be distin guished to some extent. In addition, background and atomic absorption signals obtained in the pretreatment step provided very important info rmation to clarify the interference mechanisms. In the presence of sod ium chloride, formation of a highly volatile zinc chloride contributes mainly to the losses of zinc, especially during high pretreatment tem peratures. The losses of zinc and cobalt can partly be attributed to t he occlusion of the analytes in microcrystals of the interferent and s ome of these are thrown from the furnace without decomposing early in the atomization step or during the pretreatment step. In addition, exp ulsion of both analytes together with the violently expanding matrix g ases seems to be a likely interference mechanism as well.