Benefication of titania slag by oxidation and reduction treatment

US6803024B1 · kind B1 · utility

Assignee

• Ipcor NV · NL

Inventors

• Jacobus Philippus Van Dyk · Pretoria, ZA
• Nanne Mattheus Vegter · Pretoria, ZA
• Cornelia Petronella Visser · Pretoria, ZA
• Thomas De Lange · Pretoria, ZA
• John D. Winter · Houston, US
• Ernest A. Walpole · Newcastle, AU
• Johannes Nell · Johannesburg, ZA

Key dates

• Filing date: Jun 15, 2001
• Grant date: Oct 12, 2004
• Expiry date: Jun 15, 2021

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01P2006/80
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

This invention relates to a method of treating titania slag to increase the leachability of impurities from the slag consisting of the steps of sizing the titania slag to a particle size from 75 to 850 &mgr;m; oxidizing the sized slag particles at a temperature from about 700° C. to below about 900° C. causing the iron present in the slag to concentrate at the exposed surfaces of the slag particles and/or causing an anatase phase to stabilize in the slag, causing a major portion of the iron in the Fe(II) state to convert to the Fe(III) state, and causing the titanium in the Ti(III) state to be converted to the Ti(IV) state; and reducing the oxidized slag in a reducing atmosphere from about 700° C. to about 950° C. to convert a major portion of the iron in the Fe(III) state to the Fe(II) state. The invention also relates to a method of beneficiating titania slag to increase the TiO2 content thereof wherein the above treated slag is leached with acid.