A method for recovering rare earth and aluminum from the leaching solution of weathering crust elution type rare earth ore to remove impurities

Abstract

The invention relates to a method for recovering rare earth and aluminum from weathered crust ion-adsorption type rare earth ore lixivium impurity-removal slags, which comprises the following steps: (1) adding an acid solution into the impurity-removal slags, continuously stirring for 4-8h under the condition that the temperature is controlled at 10-70 DEG C, and filtering the obtained object so as to obtain rare earth and aluminum containing filtrate and waste residues; (2) adding an alkaline solution into the rare earth and aluminum containing filtrate until the pH value of the obtained mixture is 5.0-5.5, so that an aluminum hydroxide precipitate is generated in the filtrate, and filtering the filtrate so as to obtain the aluminum hydroxide precipitate and rare earth containing filtrate; (3) washing the aluminum hydroxide precipitate by using clean water, filtering the obtained object, and carrying out low-temperature drying on the aluminum hydroxide precipitate so as to obtain aluminum hydroxide or carrying out high-temperature calcining on the aluminum hydroxide precipitate so as to obtain an alumina product; and (4) adding an alkaline solution into the rare earth containing filtrate, adjusting the pH value of the filtrate to 6.5-6.5, aging for 6-24h, and filtering the obtained product, so that a rare earth precipitate and filtrate are obtained, and washing, filtering and drying the rare earth precipitate so as to obtain a rare earth product. The method disclosed by the invention is simple in process, rare earth and aluminum are recovered from weathered crust ion-adsorption type rare earth ore lixivium impurity-removal slags by using a cheap and easily-obtained reagent, the recovery rate is high, and the purity of recovered aluminum and rare earth products is high, therefore, the method has good economic benefits.

Description

technical field [0001] The invention belongs to the technical field of hydrometallurgy, and in particular relates to a method for recovering rare earth and aluminum from leaching liquid of weathering crust leaching type rare earth ore to remove impurities. Background technique [0002] In a warm and humid climate, through biological, physical and chemical actions, protoliths such as granite and volcanic rocks are gradually weathered into clay minerals such as halloysite, illite, kaolinite and montmorillonite, while rare earth minerals are weathered to form rare earth ions . Rare earth ions are adsorbed on clay minerals as hydrated or hydroxyl hydrated ions to form weathering crust leaching type rare earth ores. The mine has the characteristics of wide distribution, many ore spots, small scale, low raw ore radioactivity, complete rare earth distribution and rich medium and heavy rare earths. Among them, medium and heavy rare earths account for more than 80% of the world's re...

AI Technical Summary

Problems solved by technology

During the impurity removal process, about 3-8% of rare earths will form hydroxides and precipitate into the impurity removal residue, resulting in the loss of rare earths

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