Purification of pigment grade titanium dioxide by processing in molten salts

D. Strusevich, A. Maries, M. Tyrer, D. Inman, S. J R Simons, J. A. Gisby

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

An alternative method of purifying the mineral rutile (TiO2) is reported. This offers potential savings in process energy and reduced waste when compared with current technology. The work reported here focused on refining rutile sand (95%TiO2) containing transition metal oxides (Fe 2O3, SiO2, ZrO2, Cr 2O3, V2O5 and Al2O 3), which impart a strong colour to the mineral concentrate. The objective was to remove the colour giving oxides to produce rutile of over 99% purity (which is white in colour). Complete dissolution in molten salt (alkali chloride-fluoride) at 750°C allowed electroseparation of the transition metals between a graphite anode and a stainless steel cathode. The voltage maintained across the cell ensured removal of transition metal ions from the solution, with minimal loss of titanium. In this process, dissolution of TiO2 was enhanced by partial replacement of chloride by fluoride in the melt to allow the complex ion TiF2- 6 to dominate the titanium speciation. This had the additional advantage of minimising losses of Ti as volatile TiCl4.

Original languageEnglish
Pages (from-to)133-138
Number of pages6
JournalTransactions of the Institutions of Mining and Metallurgy, Section C: Mineral Processing and Extractive Metallurgy
Volume120
Issue number3
DOIs
Publication statusPublished - 2011
Externally publishedYes

Keywords

  • Molten salts
  • Pigment
  • Purification
  • Rutile
  • Sodium chloride
  • TiO

ASJC Scopus subject areas

  • Geotechnical Engineering and Engineering Geology
  • Geochemistry and Petrology
  • Chemistry(all)

Fingerprint Dive into the research topics of 'Purification of pigment grade titanium dioxide by processing in molten salts'. Together they form a unique fingerprint.

  • Cite this