Monazite ore comprehensive utilization and recovery process

Abstract

The invention relates to a monazite ore comprehensive utilization and recovery process, wherein monazite and xenotime and other associate minerals are completely separated through mineral dressing, and alkali decomposition treatment, preferred dissolving, complete dissolving and extraction separation are used, such that the recovery rate of rare earth, uranium and thorium is improved, and the production of radioactive waste residue is reduced. According to the present invention, the comprehensive utilization of the radioactive waste residue is achieved, the amount of the radioactive waste residue is reduced, and the environmental pollution is avoided; during the mineral dressing process, the titanium-containing ilmenite and the monazite are separated, such that the problem that titanium enters the subsequent rare earth, uranium, thorium extraction process so as to easily cause the generation of the three-phase matter is avoided; and H2O2 is added during the preferred dissolving process of the hydrochloric acid, such that the recovery rate of the rare earth is easily increased, and the extraction separation pressure of the subsequent complete dissolving residue is reduced.

Description

technical field [0001] The invention relates to a monazite ore comprehensive utilization and recovery process, specifically a method of thoroughly separating monazite from xenotime and other associated minerals through ore dressing, and then using alkali decomposition to process monazite to improve the recovery rate of rare earth, uranium and thorium , a process for reducing the generation of radioactive waste residues, belonging to the field of rare earth ore smelting and production. Background technique [0002] Monazite is one of the important rare earth ores. It also contains a considerable amount of uranium, which is a nuclear fuel urgently needed by the country at present, and contains a high content of thorium, which is a valuable resource for future important nuclear fuels. [0003] At present, the monazite mineral content in the industrially obtained concentrate can reach more than 95%, and the rest are associated minerals such as zircon sand, xenotime, and ilmenite...

AI Technical Summary

Problems solved by technology

[0006] First, monazite concentrate contains xenotime associated with it, its crystal form is stable, and it is difficult to decompose by monazite alkaline treatment, so after the hydrochloric acid is completely dissolved, there will still be a total amount of 5%-10% fully dissolved slag that cannot be dissolved , the total melting slag contains rare earth, uranium, thorium and other valuable elements, which belongs to radioactive slag, causing waste of resources and environmental problems;

[0007] Second, ilmenite is associated with monazite, so it mainly enters the thorium uranium (rare earth) excellent slag during the subsequent alkali decomposition and hydrochloric acid excellent dissolution process. After entering the [RE+Th+U+Fe] material liquid, as the pH value of the system changes, the titanium element is easily hydrolyzed to form titanium hydroxy complexes and titanium oxide, etc., and the extraction process is easy to form three-phase substances, resulting in poor phase separation during extraction. Well, continuous operation cannot be carried out. In industrial production, the feed liquid must be hydrolyzed to remove Ti, adjust the pH value and perform multiple filtration, clarification and washing treatments, which brings operational difficulties