ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Hydrolysis of titanium sulphate compounds

Barbara U. Grzmil, Daniel Grela, and Bogumił Kic

Institute of Chemical and Environment Engineering, Szczecin University of Technology, ul. Pulaskiego 10, PL 70-322 Szczecin, Poland

E-mail: barbara.grzmil@ps.pl

Received: 26 March 2007  Revised: 6 June 2007  Accepted: 23 June 2007

Abstract: The influence of TiOSO₄ and free sulphuric acid concentrations in the starting solution on the degree of titanyl sulphate conversion to hydrated titanium dioxide and post-hydrolytic sulphuric acid was studied. Titanyl sulphate solution, an intermediate product in the commercial preparation of titanium dioxide pigments by sulphate route, was used. It was found that the degree of hydrolysis markedly depends on the studied parameters. The lower was the content of TiOSO₄ in the starting solution, the higher conversion was achieved. The degree of hydrolysis at the final stage varied between 81 % (420 g TiOSO₄ dm⁻³, 216 g H₂SO₄ dm⁻³) and 92 % (300 g TiOSO₄ dm⁻³, 216 g H₂SO₄ dm⁻³). The same relation was obtained when changing the concentration of free H₂SO₄ in the starting solution. The degree of hydrolysis at the final stage varied between 49 % (261 g H₂SO₄ dm⁻³, 340 g TiOSO₄ dm⁻³) and 96 % (136 g H₂SO₄ dm⁻³, 340 g TiOSO₄ dm⁻³). The particle size of the obtained hydrated titanium dioxide (HTD) also depends on the initial solution composition.

Keywords: hydrated titanium dioxide - hydrolysis - sulphate process - titanyl sulphate

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-007-0074-8

Chemical Papers 62 (1) 18–25 (2008)