Determination of bismuth and lead in geological samples by electrothermal AAS .1. Comparative study of tungsten containing chemical modifiers


Acar O., Turker A., Kilic Z.

FRESENIUS JOURNAL OF ANALYTICAL CHEMISTRY, vol.357, no.6, pp.656-660, 1997 (SCI-Expanded) identifier identifier

Abstract

A comparative study on the efficiency of some tungsten containing chemical modifiers such as W, W+Pd, W+Rh, W+Pt and W+Ru for thermal stabilization of Bi, In, Pb and Sb has been performed systematically by a Zeeman electrothermal atomization atomic absorption spectrometer (ETAAS). The addition of tartaric acid (TA) as a reducing agent additionally to the mixed modifiers was studied. A mixture of W+Pd+TA was found to be a powerful mixed modifier for the determination of Bi, In, Pb and Sb. Pretreatment temperatures could be increased up to 1250-1500 degrees C using this mixed modifier. The use of the mixed modifier results in an enhanced accuracy and precision of the method and recovery rates above 97% for all samples. The W+Pd+TA mixed modifier was applied to the determination of Bi and Pb in dissolved geological reference samples.