Progress on Extraction of Valuable Metals Elements from Red Mud

As a kind of alkaline waste produced in the alumina production process, red mud has a high annual output, large stockpiles, and low utilization rate in this country, which poses a huge threat to the resources and environment. Extracting a large amount of valuable metal elements contained in red mud is of great significance for realizing the resource utilization of red mud. This article briefly describes the nature and composition of red mud. Research status and existing problems of extraction of valuable metal elements from red mud such as the direct magnetic separation, reduction-magnetic separation and wet processes of Fe, the reduction sintering method, calcification-carbonation method, acid leaching method and sub-molten salt extraction process of Al, fire and wet extraction process of Ti; and the combined fire-wet and wet extraction process of Sc were reviewed. TIt is believed that the current challenge for industrialized recovery of valuable metals in red mud lies in the complex composition of red mud, which leads to the technical difficulty and processing cost of valuable metal recovery, and the lack of process research on the systematic recovery of multiple elements. It is proposed that the development of more efficient technologies for the recovery of valuable metals and the strengthening of relevant research on the systematic extraction of multiple valuable metals from red mud are the keys to the realization of red mud resource utilization in the future.