Determination of germanium at trace levels in environmental matrices by chloride generation-inductively coupled plasma atomic emission spectrometry

Abstract

A study was undertaken to evaluate the analytical capabilities of coupling chloride generation with inductively coupled plasma atomic emission spectrometry for the determination of germanium at trace levels. The method is based on the generation of germanium tetrachloride by concentrated hydrochloric acid in a continuous system and subsequent introduction of the gaseous analyte via the inlet tube of the plasma torch. After optimizing the conditions for GeCl ₄ generation as well as the plasma parameters, the method was applied to the determination of germanium in sediments, fly ashes and geological samples. A detection limit (3σ _blank ) of 0.25 ng ml ^–1 was obtained. The precision (RSD) of the determination was 2.7% at a level of 100 ng ml ^–1 Ge and 4.6% for 10 ng ml ^–1 (n=10). The interferent effect of various ions (As, Cd, Co, Cu, Fe, Ga, Hg, Ni, Pb, Sb, Se, Sn, Te, Zn) on the germanium signal was evaluated. Hydride generation and chloride generation of Ge were compared in terms of selectivity, sensitivity and precision.