Method for extracting titanium from red mud

Abstract

The invention relates to a method for extracting titanium from red mud. According to the scheme, the method comprises the steps of carrying out water leaching and dealkalization operation on the red mud to obtain a water leachate and water leaching resides; collecting the water leachate as a pH value regulator for subsequent titanium dioxide hydrolysis operation, and carrying out two-stage secondary acid leaching operation on a mixed solution of the water leaching residues, sulfuric acid and citric acid in an acid leaching tank to obtain tailings and qualified acid leachate containing titanium; then, mixing the qualified acid leachate containing titanium and an organic solvent, and carrying out five-stage extraction to obtain a saturated organic phase and a raffinate; returning the raffinate as a leaching agent to acid leaching operation; mixing the saturated organic phase and a back extraction agent, and carrying out six-stage extraction to obtain an organic waste phase and a back extraction solution; after regenerating the organic waste phase, recycling the organic waste phase to extraction operation; after regulating the pH value of the back extraction solution by using the water leachate obtained by dealkalization operation, carrying out hydrolysis operation; and calcining a hydrolysis product to obtain a titanium dioxide product with the purity of larger than 99.5% and the titanium recovery rate of larger than 80%. The method has the advantages of simple process, low agent consumption, high product purity, high titanium recovery rate and wastewater recycling.

Description

Technical field [0001] The present invention is the field of red mud wet metallurgical technology, which involves a method of red mud titanium lifting. Background technique [0002] Chi Mud is an alkaline solid waste produced in the process of producing aluminum oxide in aluminum ore. It is also a secondary mineral resource containing a variety of valuable metals.Depending on the production of aluminum ore production and production technology, the types and contents of the valuable metals in red mud will also be different.One of the important resources. [0003] At present, the method of extracting titanium from red mud is mainly to obtain titanium dioxide (Zhu Guohai, Wang Keqin, Wang Hao, et al. Research on titanium dioxide (Zhu Guohai, Wang Keqin, Wang Hao, etc. [J].. Ponal metal (smelting parts), 2012, 7: 23-26; agatzini, l.s., outadakis, p., tsakiridis, p.e., et al. Titanium lead by redHazardous Materials, 2008, 157: 579-586).The titanium in the red mud is mainly in the form...

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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