Alumina production mainly adopts Bayer method, sintering method and combined method, and a certain amount of industrial waste—red mud is produced in the production process. The main chemical components of red mud are aluminum oxide, iron oxide, titanium oxide, calcium oxide, silicon dioxide, and sodium oxide. In addition, it also contains precious scattered metal elements such as scandium, gallium, and vanadium. The content of iron and aluminum in the red mud produced by the Bayer method is relatively high, the iron oxide is between 20-60%, and the alumina is between 10-20%; the content of calcium oxide and silica in the red mud produced by the sintering method and the combined method high.

Recovery of Scandium from Red Mud

Scandium is a precious scattered element, which is widely used in the fields of luminescent materials, aerospace, alloys and batteries. Scandium is widely distributed in bauxite. In the process of alumina production, scandium is brought into industrial waste red mud. The content of scandium in red mud is usually around 0.02%, and some are as high as 0.05%. Scandium-containing red mud is important for the production of scandium products. source of raw materials.

Aluminum Recovery from Red Mud

The Bayer red mud contains a certain amount of aluminum resources, which is about 15% based on alumina. Aluminum recovery from red mud mainly includes fire method and wet method.

Recovery of Titanium from Red Mud

Titanium in red mud mainly exists in the form of perovskite (CaTiO3), and the proportion of titanium in red mud is between 2.5% and 22.6%.

Recovery of Iron from Red Mud

The iron content in red mud is between 10% and 45%, and the phases are mainly hematite, magnetite and goethite. The main methods for separating iron from red mud are physical separation, reduction-magnetic separation and wet method.

Red mud contains a variety of valuable elements, especially scandium and gallium, which are precious scattered metals and important strategic resources. The iron, aluminum, titanium, scandium, and Separation and extraction of gallium, etc., to produce related compounds required by the market, not only can create significant economic benefits, social benefits and environmental benefits, but also help the sustainable development of my country’s alumina industry, and help meet the needs of social and economic development for iron-containing battery materials And scandium, gallium strategic resource needs, has very important strategic significance.