Contamination-free decomposition of zirconium oxide for the determination of ultra-trace silicon by inductively coupled plasma-atomic emission spectrometry Original Research Article

Using the specially designed Pt-lined PTFE vessel, zirconium oxide was completely decomposed with (1+3) sulfuric acid at 250°C. The procedure blank of Si was 0.01 μg ml−1, which corresponded to 2 μg Si g−1 in a sample. This blank value from the vessel was 10% of that obtained with a commercial vessel, and almost similar to the detection limit of the inductively coupled plasma-atomic emission spectrometer used. The use of this improved vessel enabled one to determine ultra-trace Si in various zirconium oxide samples; the analytical values were compared to those obtained after alkali fusion methods.