Method for recovering rare earth in ion adsorption type rare earth ore leaching solution through fractional precipitation

Abstract

The invention discloses a method for recovering rare earth in an ion adsorption type rare earth ore leaching solution through fractional precipitation. According to the method, firstly, a magnesium-containing alkaline compound is added to a purified ion adsorption type rare earth ore leaching solution for a precipitation reaction; and then a calcium-containing alkaline compound is further added for a precipitation reaction, and rare earth precipitation concentrates and precipitation mother liquor are obtained after solid-liquid separation. According to the method, raw materials adopted are cheap and easy to obtain, and the process is simple and easy to control, so that the production cost is lowered; the problem of ammonia and nitrogen pollution in the precipitation process of the ion adsorption type rare earth ore leaching solution is solved; meanwhile, the adding amount of the magnesium-containing / calcium-containing alkaline compound is controlled, so that a precipitant is dissolved fully as much as possible, and the purity of the rare earth precipitation concentrates is improved; in addition, sulfate ions and calcium ions in the leaching solution can form a small amount of calcium sulfate precipitate with the good crystallization property; crystals of rare earth hydrate can be induced, and the problem that the rare earth hydrate is not liable to form a crystal form precipitate can be also solved.

Description

technical field [0001] The invention relates to the field of rare earth hydrometallurgy, in particular to a method for step-by-step precipitation recovery of rare earth in leach solution of ion-adsorption type rare earth ore. Background technique [0002] Since the 1970s, the strategic position of rare earth elements has been increasing day by day, and has become an indispensable and important strategic resource in the process of high-tech development and traditional industry transformation. It is known as the "vitamin of modern industry" and "treasure house of new materials". Developed countries such as the United States and Japan have listed rare earths as "strategic elements in the 21st century" for strategic reserves and key research; my country has also listed rare earth materials as Priority themes and key support directions for basic raw materials in the manufacturing industry. [0003] According to the differences in physical and chemical properties among rare earth ...

AI Technical Summary

Problems solved by technology

However, the research results of the paper "Effect of impurity ion on the preparation of novel saponifier for rare earth extraction" (Jounalofrare earth, Volume 34, Issue 1, 2013) show that in the presence of rare earths, most magnesium compounds cannot be carbonized to form magnesium bicarbonate solution, but instead form magnesium carbonate precipitation, which cannot substantially improve Purity of Rare Earth Concentrate Products

[0007] Therefore, the current ion-adsorption type rare earth ore leachate method for recovering rare earths still cannot not only reduce production costs, reduce ammonia nitrogen pollution, but also ensure the purity of rare earths in the product