A short process method for preparing low-oxygen high-purity rare earth metals

Abstract

The invention belongs to the field of rare earth metal preparation, and specifically relates to a short-flow method for preparing low-oxygen high-purity rare earth metal. Using high-purity rare earth oxides as raw materials for electrolysis in a fluoride molten salt system, the cathode precipitates rare earth metals, and collects them in the crucible, and then uses the casting device of the present invention to regularly take out the rare earth metals from the crucible, and the casting tank is filled with rare earths Lift the casting tank with the molten metal, quickly close the liquid injection pipe and the pumping / inflating pipe of the casting tank, then remove the casting tank, and cast the low-oxygen high-purity rare earth metals produced in the casting tank. The invention has simple operation, low oxygen content and high purity of the prepared rare earth metal, short process flow and low cost, and can fundamentally solve the difficult problem of low-oxygen and high-purity rare earth metal preparation.

Description

Technical field [0001] The present invention belongs to the field of rare earth metal preparation, in particular to a short process method for preparing low-oxygen high-purity rare earth metals. Background [0002] Rare earth elements have a series of special properties, widely used in metallurgy, petrochemicals, glass ceramics, atomic energy, functional materials, textiles, medicine and agriculture and animal husbandry and other fields, especially in the field of high-tech and national defense and military material preparation, rare earths have become indispensable. The addition of rare earth elements to the material can play a role in purifying the melt, metamorphic inclusion, micro-alloying, etc., significantly improving the toughness, plasticity and fatigue life of the material, etc., so that the material is more tough, heat-resistant, wear-resistant and corrosion-resistant. In addition, the material has unique optical, electrical, magnetic and other properties after the add...

AI Technical Summary

Problems solved by technology

However, the existing methods still cannot meet the requirements for preparing low-oxygen high-purity rare earth metals. The various rare earth metals produced by various methods have high oxygen content and low purity, or the packaging, transportation, storage and use of products are not Strict oxygen control is carried out, and the newly prepared low-oxygen and high-purity products are repeatedly oxidized and dirty, and the rare earth metals finally added to the material have high oxygen content and low purity, which cannot meet the requirements for high-performance material manufacturing

In recent years, many scientific researchers have also conducted a lot of research on the secondary purification technology of rare earth metals, and developed one or more combined purification methods such as vacuum smelting, vacuum distillation, electrolytic refining, electromigration, and regional smelting. Mostly it is to "redistribute" the impurities in the matrix, and it is difficult to achieve the "removal" of impurities. Although the purpose of purification can be achieved, it is often only possible to purify some impurities. In addition to increasing the operation process, it is difficult to control oxygen in the process of transport before and after the process. , so that the risk of rare earth metals being oxidized again becomes greater. These methods are not suitable for rare earth metals with low oxygen content. After the second purification, it is "counterproductive", and its oxygen content often increases significantly, and the cost increases significantly.

Some scholars also claim that high-purity rare earth metals with high purity have been prepared under laboratory conditions, with an oxygen content of less than 30ppm and a purity of 99.999%. high investment

Images