Preparation of low iron and high specific surface area cerium lanthanum oxide

Abstract

The invention relates to a method for preparing lanthana (cerium oxide) with a low content of iron and high specific surface, which is characterized by comprising method of removing Fe from lanthanum and cerous rare earth carbonate and the method of controlling the specific surface of the lanthana (cerium oxide); the method for removing Fe adopts single-stage extraction or serial extraction with a complexation settling method, namely firstly, removing Fe in LaCeCL6 to be less than 0.005wt% by using an extracting agent with an extraction method and reducing the content of Fe in LaCeCL6to be less than 0.002wt% by using a complexing agent, wherein the extracting agent is C8-C10 tertiary amine and the complexing agent is sulpho-amino niobate; lanthanum carbonate or cerous carbonate is precipitated from the ammonium hydrogen carbonate or the sodium carbonate from which Fe is removed; the specific surface of the lanthanum carbonate or the cerous carbonate is controlled by the method of increasing the temperature in a gradient elevation way, the temperature is increased to be below 800 DEG C from 320 DEG C in a gradient elevation way and is reduced to the room temperature. The method has the advantages that the lanthana (cerium oxide) with a low content of iron and high specific surface, which is produced by the technique method fully satisfying the requirement on the raw material required by the accurate and high-speed rare earth polishing material, has stable quality, is easy to implement the industrial production, and can reach the following specific technical indexes with TREO being more than or equal to 90 percent, La2O3/TREO being 25 percent to 30 percent, CeO2/TREO being between 70 percent and 75 percent, Pr6O11/TREO being less than 0.002 percent, Fe2O3 being less than 0.002 percent, and the aged specific surface being more than 30m/g.

Description

Technical field: [0001] The invention relates to a method for preparing lanthanum cerium oxide with low iron and high specific surface area, more precisely, a method for preparing rare earth oxides with high physical and chemical activity. Background technique: [0002] Lanthanum cerium is two important elements in the series of rare earth elements, and its content in bastnaesite accounts for 77%. Among them, lanthanum accounts for 25-27%, and cerium accounts for 50%. Baotou Baiyun Ebo rare earth mine accounts for 70% of the world's reserves and is a typical bastnaesite. In recent years, my country has produced 8,000 tons of cerium (calculated as rare earth oxides) every year, and its oxides, carbonates, nitrates, and chlorides are the most important products in the rare earth industry. Lanthanum cerium oxide is mainly used in catalysts and precision high-speed rare earth polishing materials. Precision high-speed rare earth polishing materials are mainly used for polishin...

AI Technical Summary

Problems solved by technology

If the specific surface area is too low, the flatness of the thrown workpiece will decrease, scratches and defects, and it is eas