Method for enriching and recovering rare earth from phosphate rock containing rare earth

Abstract

The invention discloses a method for enriching and recovering rare earth from rare earth containing phosphorus ores. The method comprises the following steps: adding the rare earth containing phosphorus ores and mixed acid of phosphoric acid and sulfuric acid to a mixed reaction tank to react to obtain mixed slurry and carrying out solid-liquid separation to obtain rare earth enriched slag and leachate; adding the leachate and proper amount of sulfuric acid to a phosphoric acid regeneration agitation tank to undergo mixed reaction, thus obtaining mixed slurry containing phosphoric acid and gypsum; returning part of the mixed slurry to the regeneration agitation tank as returned slurry and carrying out solid-liquid separation on the rest part, thus obtaining a phosphoric acid solution and gypsum slag; opening part of the phosphoric acid solution, returning part of the phosphoric acid solution to be recycled as mixed acid after adjusting the components and using the rest part to produce phosphoric acid. The method has the beneficial effects that the impurities, such as calcium, magnesium, aluminium and phosphorus, can be effectively removed and the dissolution loss of rare earth can be reduced by utilizing adsorption of little newly generated gypsum by adopting the mixed acid which mainly contains phosphoric acid and contains proper amount of sulfuric acid to leach the rare earth containing phosphorus ores, thus further achieving selective impurity removal by leaching, increasing the enrichment ratio of rare earth in slag and reducing the dissolution loss of rare earth.

Description

technical field [0001] The invention belongs to the field of enrichment and comprehensive recovery of associated rare earths, and in particular relates to a method for enriching and recovering rare earths from phosphate rock containing rare earths by leaching and removing impurities with a mixed acid of phosphoric acid and sulfuric acid. Background technique [0002] Phosphate rocks are generally associated with rare earths, and the rare earth content varies from as high as 5% to as low as 0.1%. Since rare earths exist in apatite phosphate minerals in the form of isomorphism, the enrichment effect of physical beneficiation on rare earths is poor, so rare earths can only be separated and recovered by chemical methods. Due to the low grade of rare earths and the high content of harmful impurities phosphorus and calcium, direct leaching and recovery of rare earths is difficult and costly. Relying on the phosphoric acid production process to achieve comprehensive recovery of rar...

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Problems solved by technology

[0004] The purpose of the present invention is to address the deficiencies in the prior art, especially for the problems that some rare earths in the phosphoric acid leaching and enrichment of rare earths are dissolved and the slurry is difficult to separate from the solid and liquid. Method for enriching and recovering rare earth from rare earth phosphate rock

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