Method for extracting rare earth and aluminum from ion adsorption type rare earth ores

Abstract

The invention relates to a method for extracting rare earth and aluminum from ion adsorption type rare earth ores. The method includes the steps that (1), ore leaching is performed, wherein an ore leaching agent is added for in-situ ore leaching or pond leaching, and rare earth ore leaching liquid with the rare earth concentration higher than 0.02% is obtained; (2), precipitation is performed, wherein solid and liquid separation is performed after a precipitation agent is added into the rare earth ore leaching liquid for precipitation, and precipitated filter liquor and mixed precipitate containing rare earth and aluminum are obtained; (3), calcination is performed, wherein the mixed precipitate containing rare earth and aluminum is calcinated, and calcinated products containing rare earth oxide and alpha-aluminum oxide are obtained; and (4), leaching out is performed, wherein solid and liquid separation is performed after a chlorination leaching agent is added into the calcinated products containing rare earth oxide and alpha-aluminum oxide for leaching out, chlorinated rare earth leaching-out liquid and filter residues containing alpha-aluminum oxide are obtained, rare earth oxide is extracted from the chlorinated rare earth leaching-out liquid, and aluminum oxide fine products are extracted from the filter residues containing alpha-aluminum oxide. The method is simple in technology, precipitation is directly performed without impurity removal, and by means of the dissolution property difference of the calcinated products in an acid environment, the rare earth and the aluminum can be separated and recycled.

Description

technical field [0001] The invention belongs to the technical field of rare earth metallurgy, in particular to a method for extracting rare earth and aluminum from ion-adsorption type rare earth ore. Background technique [0002] Ion-adsorption rare earth minerals are rare earth minerals that exist in an ionic state. Most of the rare earth elements in rare earth minerals exist in the state of cations and are adsorbed on certain mineral carriers. For example, the unique ion-adsorption rare earth minerals in southern my country Most of its rare earth ions are mainly adsorbed on aluminosilicate minerals such as kaolinite and muscovite or fluorocarbonate minerals, and this kind of ion-adsorbed rare earth minerals is rich in resources and widely distributed, and the ore bodies are rich in Hilly terrain on hillside ground. The ore body of this mineral is loose, with a clay sand grain structure, low radioactivity, and good permeability. Although the content of rare earths is general...

AI Technical Summary

Problems solved by technology

Impurity removal and precipitation treatment are mainly achieved by adding ammonium bicarbonate to the leaching solution to achieve "removal of impurities first, then precipitation of rare earth". However, the aluminum slag produced by ammonium bicarbonate removal and precipitation is generally in a colloidal state, and its settling performance is poor. And rare earth inclusions are more in the slag, cause bigger waste, and the aluminum slag (water content is greater than 80%) directly storage yard after starch washing also easily causes environmental pollution, the crystallization performance of the rare earth carbonate that generates after precipitation is bad, naturally Settling properties are also poor resulting in very long aging times

In addition, due to the incomplete removal of aluminum in the impurity removal stage and partial oversaturation in the precipitation process, the rare earth carbonate produced after precipitation will also contain high impurities in aluminum, calcium, and magnesium, resulting in a product with a burning rate of only about 15%. Rare earth in-situ leaching solution is difficult to transport. At present, the "impurity removal-precipitation" operation is completed in the mining area. Since the service life of the mining area is generally 3-5 years, the multi-level workshop for rare earth removal and precipitation needs to be repeated every 3-5 years. Construction, repeated infrastructure construction not only requires a lot of investment, but also destroys the vegetation in the mining area

These problems have directly or indirectly increased the production cost of rare earths, reduced the recovery rate of rare earths and aluminum in ionic rare earth ores, and caused serious environmental pollution and destruction at the same time.

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