Production of titanium dioxide nanopowders from red mud
Red mud, byproduct of the aluminum industry, poses a significant environmental problem due to its chemical composition and the large quantities generated. This study explores the potential for its valorization through a multi-step process that includes reduction, leaching with acid solution, purification, and ultrasonic spray pyrolysis (USP). In the first step, red mud undergoes carbothermal reduction, during which metal oxides are transformed into metal phase and slag. In the second step, the slag is subjected to leaching under various conditions, including changes in pressure, temperature, and acid concentration, which allows the recovery of titanium in the form of titanium oxysulfate and other metals. Finally, after purifying the solution using precipitation or solvent extraction, ultrasonic spray pyrolysis is used to synthesize titanium dioxide (TiO₂) nanopowders from titanium oxysulfate (TiOSO₄). This integrated approach not only reduces waste but also produces high-value materials with broad industrial applications.