Process-accompanying analysis of solid intermediate and end products in the manufacturing process of high-purity tungsten by ETV-ICP-OES

Many solids from the production of high-purity tungsten are challenging to analyze due to their insolubility and tungsten's high spectral line density, which causes interferences in many spectroscopic methods. To address this, electrothermal vaporization (ETV) coupled with inductively coupled plasma optical emission spectrometry (ICP-OES) was optimized for the direct multi-element analysis of various tungsten-based materials, including ammonium paratungstate ((NH4)10(H2W12O42) ∙ 4 H2O), yellow tungsten oxide (WO3), blue tungsten oxide (WO2+x), tungsten metal powder (W) and tungsten carbide (WC). The method focused on detecting critical contaminants like Al, B, P, S and Si as well as O in W and WC, which affect the characteristics of final products.