Summary of research progress on separation and extraction of valuable metals from Bayer red mud

Abstract

Bayer red mud is a strong alkaline solid waste discharged during alumina production. Due to large emissions and strong alkalinity, red mud is now mostly dammed or buried, which not only occupies huge land but also contaminates the surrounding ecosystem, causing the risk of collapse and landslide. In addition to its overall utilization in building materials, agriculture, the environment, and the chemical industry, red mud also contains valuable metals such as sodium, aluminum, iron, titanium, and scandium and is considered to be an important secondary resource. In this paper, the physicochemical properties and hazards of red mud are rst introduced, and then the overall utilization of red mud is summarized. Then, the latest research progress on the separation and extraction of valuable metals from red mud is reviewed in detail, and a new comprehensive utilization method is proposed and analyzed. This paper also provides suggestions for the future development direction of the comprehensive utilization technology of red mud.

Applying Red Mud in Cadmium Contamination Remediation: A Scoping Review

“…The saturation level spans from 91.1 to 99.6%. The plasticity index ranges from 17 to 30, while the liquid limit is 1.31 to 1.56 [38,39]. Despite its high porosity and substantial water content, red mud does not undergo shrinkage or expansion upon drying or wetting [37].…”

Study on Magnetization Roasting Kinetics of High-Iron and Low-Silicon Red Mud

“…The methods of extracting valuable metal from red mud are conventional physical methods, the pyrometallurgical method, and hydrometallurgical methods. Another method is to use red mud as a comprehensive mineral raw material, such as environmental protection functional materials, wall materials, cement, mine filling, and so on [ 11 ]. To realize the full quantitative comprehensive utilization of red mud, it is necessary to economically extract and enrich valuable elements in red mud [ 12 ].…”