Innovative processing of red mud for recovery of valuable and rare elements

Red mud, a by-product of alumina production in the Bayer process, represents a large-tonnage industrial waste and a valuable secondary source of critical elements such as gallium, vanadium, and aluminum. This study explores the hydrogarnet process as an efficient and environmentally friendly approach for recovering these elements from red mud under hydrothermal alkaline conditions. Autoclave treatment of red mud with high-modulus sodium aluminate solutions (Na?O ≈ 240 g/L) in the presence of lime at 240–260 °C leads to the formation of a stable hydrogarnet phase (3CaO·Fe?O?·2SiO?·2H?O), while simultaneously dissolving up to 98.5% Na?O, 65.3% Al?O?, 55.5% Ga, and 65.8% V?O? into the liquid phase. A subsequent two-stage carbonization process enables selective recovery of gallium and vanadium in the form of a Ga–V concentrate containing 0.32% Ga and 3.7% V?O?. The resulting hydrogarnet residue has low alkali content and can be reused in building materials, reducing waste generation and environmental impact. The proposed process allows simultaneous extraction of valuable elements and neutralization of red mud alkalinity, creating a closed-loop and sustainable utilization scheme. Thus, the hydrogarnet process represents a promising direction for transforming red mud from an environmental liability into a valuable resource for obtaining critical metals and alumina product.

Dr. Abikak Yerkezhan researcher and innovator in the field of mineral processing and metallurgy. Author of more than 15 scientific papers published in high-ranking international journals (Q1–Q2, Scopus/WoS) and 6 patents related to ore processing and metallurgical technologies. Her research interests include hydrometallurgy, sorption and leaching processes, as well as integrated processing of mineral and industrial wastes. She focuses on developing environmentally safe and economically efficient technologies for the recovery of valuable and rare elements from ores and industrial residues.