A method for recovering rare earth from the process of decomposing phosphate rock with nitric acid

Abstract

The invention discloses a method for comprehensively recovering rare earth from phosphate rock containing rare earth. The rare earth-containing phosphate rock is leached with nitric acid solution, and then the solid-liquid separation is obtained to obtain the rare earth-containing solution. It does not need to be neutralized. The rare-earth-containing solution can be extracted-back-extracted under strong acid conditions to recover rare earth elements. By adding nitric acid for leaching, the presence of phosphoric acid in the leaching solution increases the acidity of the leaching solution, which further promotes the extraction efficiency of rare earths. The extraction efficiency can reach more than 98%, and the phosphoric acid does not extract, and the impurity ions are almost not extracted. It realizes good separation of phosphorus and rare earth in phosphate rock, can broaden the product chain of nitrophosphate fertilizer enterprises, and creates a road of comprehensive recovery and utilization of rare earth resources, which is beneficial to the utilization of rare earth-containing phosphate rock resources.

Description

technical field [0001] The invention relates to the field of rare earth recovery, in particular, it provides a method for efficiently recovering rare earths from strong acid leachate containing rare earths. Background technique [0002] With the rapid development of science and technology today, rare earths, known as industrial "gold", have been widely used as strategic resources in new materials, chemicals, national defense technology, energy, aerospace, etc. field. Rare earth-containing phosphate rock is a potential rare earth resource, and it is of great significance to carry out research on comprehensive recycling of rare earths. Aiming at the low content of rare earth in phosphate rock and its special occurrence state, many researches on recycling processes have been carried out. [0003] Rare earth minerals mainly include bastnaesite, monazite, xenotime and ion-adsorbed rare earth minerals. At present, there are two main ways to recover rare earths in monazite: [0...

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Problems solved by technology

[0009] (3) Phosphoric acid treatment of phosphate rock process, the rare earth-containing phosphate rock is mixed with phosphoric acid solution for reaction, more than 85% of the rare earth enters the slag, and then hydrochloric acid, nitric acid, or sulfuric acid is used to dissolve the rare earth in the recovered slag, but the slag The grade of rare earth is very low, the content of impurities such as phosphorus, calcium and magnesium is high, and the recovery rate of rare earth is low;

To sum up, it can be seen that the two extractants P204 and P507 cannot efficiently extract rare earth elements in a strongly acidic medium, so the phosphate rock leaching solution with high acidity must be neutralized with alkali before extraction to reduce the acidity, which increases the acidity adjustment process and improves production. cost, and a large amount of waste water is generated

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