Rapid determination of Ti in TiO2 by ICP OES

Abstract

A rapid method for the determination of titanium in titanium dioxide pigments and related materials by inductively coupled plasma optical emission spectrometry (ICP OES) is presented. Complete decomposition of TiO₂ was achieved in a medium of (NH₄)₂SO₄/H₂SO₄. Following a suitable dilution of the digest, Ti was quantitated based on external calibration using the 337.280 nm line and sample introduction with a OneNeb® nebulizer. A detection limit (3 s, n = 10) of 10 μg g⁻¹ and a LOQ (10 s, n = 10) of 50 μg g⁻¹ were realized. Eight samples of TiO₂ pigments and two samples of masterbatch pigment resin were analysed, providing results similar to those obtained by both traditional titrimetric and spectrophotometric methods but with standard deviations between 0.01 and 1%, some two-fold better than that of the traditional methodology. This simple procedure has been adopted by the Institute of Technology of Paraná – TECPAR (Curitiba, Brazil).