Multi-element characterization of titanium(IV) oxide by electrothermal atomic absorption spectrometry, inductively coupled plasma atomic emission spectrometry, inductively coupled plasma mass spectrometry and total reflection X-ray fluorescence spectrometry after matrix–analyte separation

Abstract

A matrix–analyte separation technique for the trace characterization of titanium(IV) oxide has been developed based on adsorption of the analytes on a column of the cation exchanger Dowex 50WX 8 from 0.1 mol l^–1 HF followed by their elution with 4 mol l^–1 HNO₃ in the opposite flow direction. The removal of the titanium matrix with a separation factor > 10⁴ was achieved. The separation technique developed was applied to the analysis of two titanium(IV) oxide powders of different purity grade by electrothermal atomic absorption spectrometry, inductively coupled plasma atomic emission spectrometry, inductively coupled plasma mass spectrometry and total reflection X-ray fluorescence spectrometry. The results, including those obtained by neutron activation analysis, are compared. For all the determination methods used, the limits of detection are given and the capabilities of the methods are compared and discussed.