Recovery of valuable metals from bauxite residue (BR) using decarbonizing technologies

Bauxite residue, also known as red mud (RM) is waste produced during alumina production in Bayer process. It is posing a significant threat to the enivorment due to its high alklalinity, fine particle size and complex structure various compounds. This study presents a sustainable, approach to its utilization, with focus on the recovery of valuable metals such as titanium. Different decarbonizing technologies were used presented in this work: hydrogen reduction without smelting in rotary kiln, high pressure leaching in an autoclave, ultrasonic spray pirolysis and aluminothermic reduction. Firstly red mud was subjected to hydrogen reduction in order to selectively remove iron, which can be used and transfered in the steel industry. Separation of Iron and solid residue was done using magnetic property of iron and magnetite, Solid residue is further processed in acid leaching with high pressure of oxygen in an autoclave. Leaching process optimizes various process parameters to extract titanium in the form of titanium oxy sulfate as well as iron and aluminium. Additionally, aluminum and iron solutions were also obtained by this process. The remaining solid residue, primarily composed of calcium sulphate and silica, was evaluated for potential use as an adsorbent in wastewater treatment. This innovative process demonstrates an efficient method of bauxite residue utilization with near zero waste concept, offering a promising solution to both environmental and industrial challenges. The planned improvement of proposed research strategy can be reached using solvent extraction and remelting process.