Recovery of Scandium, Aluminum, Titanium, and Silicon from Iron-Depleted Bauxite Residue into Valuable Products: A Case Study

Bauxite residue is a high-iron waste of the alumina industry with significant contents scandium, aluminum, and titanium. This study focuses on recovery Sc, Al, Ti, Si from iron-depleted bauxite (IDBR) into valuable products. Iron depletion was carried out using reduction roasting followed by low-intensity magnetic separation to enrich in Sc reduce an adverse effect iron scandium extraction. Hydrochloric high-pressure acid leaching, aluminum precipitation saturation leachate, solvent extraction di(2-ethylhexyl) phosphoric (HDEHP) tributyl phosphate (TBP), alkaline leaching subsequent silica were used obtain appropriate selective concentrates. As result, concentrate 94% Sc2O3, crude 93% Al2O3, titanium 41.5% TiO2, white carbon 77% SiO2 prepared characterized. Based characterization treatment stages obtained products, prospect for application suggested flowsheet discussed.