Determination of SiO₂ in Zinc Concentrates by Inductively Coupled Plasma-Atomic Emission Spectrometry

The zinc concentrates were digested by alkali fusion. The SiO₂ in zinc concentrates were determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES) with adding Au as internal calibration. The matrix interference effect was studied in this article. The matrix interference effect and the stability of instrument were worse along with Na increasing, which reduced accuracy of determination. The matrix interference effect and the instrument fluctuation have been overcome by using internal calibration. The determination limit of SiO₂ was 0.0063 mg/L, and the determination content range was of 0.02%-10%. The results were in good agreement with the certified value of reference materials and the RSD (n=5) was less than 2%.