Direct analysis of titanium dioxide solid powder by fluorination assisted electrothermal vaporization inductively coupled plasma atomic emission spectrometry

Abstract

Fluorination assisted electrothermal vaporization (ETV) was employed as sample introduction technique for the direct determination of trace amounts of impurities in titanium dioxide solid powder by inductively coupled plasma atomic emission spectrometry (ICP-AES). A polytetrafluoroethylene (PTFE) emulsion is used as a fluorination reagent to promote the vaporization of impurity elements in TiO 2 powder from the graphite tube; the vaporization behavior of matrix element (Ti) and analyte (Cr, Cu, Fe and V) were studied. Under the selected conditions, about 100 μg solid sample (10 μl of 1% m/v TiO 2 slurry) was pipetted into furnace, a pre-volatilization of the matrix could be performed by an ashing time of 70 s at 800°C to eliminate the matrix effect, and then the analytes were vaporized into plasma at the vaporizing temperature of 2600°C. Calibration was performed using the standard addition method. The accuracy was checked by comparison of the results with solution fluorination assisted ETV-ICP-AES and pneumatic nebulization (PN)-ICP-AES based on the wet-chemical decomposition. Limits of detection between 0.07 μg g −1 (Cr) and 0.2 μg g −1 (V) were achieved.