Determination of titanium in titanium dioxide pigments, paints and other materials by chromium(II) chloride reduction and automatic potentiometric titration

Abstract

A method is described for the determination of titanium in pigments, paints and other materials based on reduction of the titanium in the dissolved sample with chromium(II) chloride solution followed by automatic potentiometric titration with iron(III) ammonium sulphate. The precision and accuracy are as good as those obtained by manual methods and a repeatability of 0.25% as TiO₂ for duplicate analyses of pigment samples is achieved. Among other advantages, an estimated saving in operator time of at least 10 min per sample compared with existing methods is obtained.