Method for enriching rare-earth elements from red mud

Abstract

The invention relates to a method for enriching rare-earth elements from red mud, belonging to the technical field of enriching rare-earth elements and aiming to provide a method for removing silicon and aluminum in red mud and enriching rare-earth elements in the red mud to solve the technical problem. The invention adopts the technical scheme that the method for enriching rare-earth elements from red mud comprises the following steps of: (1) obtaining a red mud hydrochloric acid leaching solution; (2) carrying out desilication treatment to the red mud hydrochloric acid leaching solution obtained in the step (1); (3) adding a NaOH solution at a room temperature to the desilicated red mud hydrochloric acid leaching solution obtained in the step (2), finishing precipitating and separating solid and liquid to obtain a solid containing rare-earth elements; and (4) carrying out dealuminzation treatment to the solid containing rare-earth elements obtained in the step (3). The invention effectively solves an emulsification phenomenon when extracting the rare-earth elements by using a wet method and improves the extraction rate of the rare-earth elements and the purity of the product.

Description

technical field [0001] The invention discloses a method for enriching rare earth elements from red mud, belonging to the technical field of enriching rare earth elements. Background technique [0002] Red mud is the residue produced when bauxite is leached by strong alkali in the alumina production process. For every ton of alumina produced, 0.8 to 1.5 tons of red mud are produced. It is estimated that the world's aluminum industry produces about 90 million tons of red mud every year. my country is a major producer of alumina. In 2009, it produced 23.78 million tons of alumina, accounting for about 30% of the world's total output, and nearly 30 million tons of red mud were produced. Ton. At present, the comprehensive utilization rate of red mud in my country is only 4%, and the accumulated stockpile has reached 200 million tons. With the annual increase of alumina production in my country and the gradual decrease of bauxite grade, the annual production of red mud will conti...

AI Technical Summary

Problems solved by technology

At present, there are many reports on extracting rare earth elements from red mud, but there are many disadvantages in extracting rare earth elements directly from red mud, such as: due to the presence of a large amount of impurity elements such as aluminum and a small amount of silicon in the acid leaching solution, when using organic solvents to extract , the emulsification phenomenon is serious, the recovery rate is low, etc., therefore, there is no report of industrialized large-scale production