Determination of V, Ti, Co and Ni in Vanadium and Titano Magnetite by Inductively Coupled Plasma-Atomic Emission Spectrometry

Vanadium and titano magnetite was melted by sodium peroxide, then extracted by HCl. The sample solution was diluted before V₂O₅, TiO₂, Co and Ni were simultaneously directly determined by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES). 1.5 g Na₂O₂ and 10 mL HCl were used in the chemistry procedure. The analysis spectral lines of 292.4 nm, 334.9 nm, 230.7 nm and 231.6 nm were selected to measure V, Ti, Co and Ni based on less interference elements and matrix interference. The detection limits of the method were 0.17 μg/g for V₂O₅, 0.05 μg/g for TiO₂, 0.06 μg/g for Co and 0.011 μg/g for Ni under the dilution factor of 10 (the sum dilution factor was 5000). The reliability of the method has been tested by determination of those elements in national standard reference materials of GBW 07225, GBW 07226a and GBW 07227. The results were in good agreement with certified values, with a precisions of 0.41%-1.91% (RSD, n=12). The REs were less than 5% except for Ni and Co. The instalment of an Ar humidifier resolved the effect of high salinity. The matrix effect was overcome by the addition of the same amount of blank solution with the standard solution. This method exhibited simplicity, rapidity, good reproducibility and wide linearity making it suitable for multi-elemental determination.