Upgrading a rutile concentrate produced from Athabasca oil sands tailings

摘要

A rutile concentrate recently produced by Lakefield Research Ltd and Syncrude Canada Ltd from athabasca oil sands tailings was characterized and attempts were made to upgrade it to market-grade. The rutile concentrate contained 75.5% TiO_2, 18.7% Fe_2O_3, 1.03% Al_2O_3, 1.94% SiO_2, and 563 ppm Th + U. The amount of rutile (anatase) in the concentrate was estimated to be about 10―17%, and the remaining TiO_2 came from ilmenite in various altered forms. Magnetic separation could remove the Fe from the concentrate but it increased the SiO_2 content from 1.94 to 6.01 %. A reverse flotation process was developed to remove the SiO_2. Although the fine dissemination of SiO_2 in the rutile matrix limited the removal of SiO_2, the upgraded rutile concentrate, containing 87―89% TiO_2, could be used as a feedstock to the chloride titanium pigment processes.