A method for extracting titanium from red mud

Abstract

The invention relates to a method for extracting titanium from red mud. The scheme is to firstly carry out water immersion dealkalization of red mud to obtain water immersion liquid and water leaching slag, collect the water leaching liquid as a pH adjuster for the subsequent titanium dioxide hydrolysis operation, and mix the water leaching residue with sulfuric acid and citric acid in acid Perform secondary acid leaching operations in the immersion tank to obtain tailings and qualified titanic acid-containing leaching solution, then mix qualified titanic acid-containing leaching solution with organic phase for five-stage extraction to obtain saturated organic phase and raffinate, and raffinate As a leaching agent, it returns to the acid leaching operation. The saturated organic phase is mixed with the stripping agent for six-stage stripping to obtain the waste organic phase and stripping liquid. After the waste organic phase is regenerated, it is reused for extraction operations. After adjusting the pH value, the hydrolysis operation is carried out, and the hydrolyzed product is calcined to obtain a titanium dioxide product with a purity greater than 99.5%, and the titanium recovery rate is greater than 80%. The invention has the advantages of simple process, low medicament consumption, high product purity, high titanium recovery rate and recyclable waste water.

Description

technical field [0001] The invention belongs to the technical field of red mud hydrometallurgy, and in particular relates to a method for extracting titanium from red mud. Background technique [0002] Red mud is an alkaline solid waste produced during the production of alumina from bauxite, and it is also a secondary mineral resource containing a variety of valuable metals. According to the different bauxite origin and production process, the types and contents of valuable metals in red mud will also be different, but almost all red mud in various places contains titanium dioxide, the grade is generally 4% to 15%, which is the main source of titanium extraction. One of the important resources. [0003] At present, the methods of extracting titanium from red mud are mainly sulfuric acid leaching, direct hydrolysis of titanium-containing leaching solution, and calcination of hydrolyzed products to obtain titanium dioxide (Zhu Guohai, Wang Keqin, Wang Hao, et al. Research on ...

AI Technical Summary

Problems solved by technology

Titanium in red mud mainly exists in the form of perovskite and brookite minerals, wrapped by other gangue minerals, dilute acid is difficult to extract the titanium, and because red mud also contains alumina, iron oxide, Calcium oxide, sodium oxide, potassium oxide and other acid-consuming substances, so a large amount of sulfuric acid is usually required in the process of acid leaching titanium, resulting in low leaching rate of titanium, high concentration of hydrogen ions, iron, aluminum and other impurities in the acid leaching solution.

The resulting titanic acid-containing immersion solution is hydrolyzed after adjusting the pH value with sodium hydroxide. The amount of sodium hydroxide is large, and the hydrolyzate has many impurities, resulting in low purity of the final product titanium dioxide.

[0004] Therefore, this method has the disadvantages of large consumption of sulfuric acid in the leaching process, low pH value of the leach solution, low titanium recovery rate, high impurity content, large amount of medicament in the hydrolysis process, many impurities in the hydrolyzed product, low purity of the product titanium dioxide, and difficult treatment of acidic wastewater generated during the process. and other defects

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