Nanometer cerium oxide and preparation method thereof

Abstract

The invention discloses nanometer cerium oxide, and a preparation method thereof. The preparation method comprises following steps: a cerium salt, and a carbonate or an oxalate are mixed at a molar ratio of 1: (1-3), an alcohol dispersant is added for full grinding reaction, after reaction, washing and drying are carried out to prepare a precursor, and the precursor is subjected to calcining. According to the preparation method, the cerium salt, and the carbonate or the oxalate are taken as raw materials, the alcohol dispersant is added, at alcohol environment, solid phase chemical reaction iscarried out, grinding is adopted to prepare the precursor, and calcining is adopted to prepare the cerium oxide powder. The cerium oxide powder prepared using the preparation method is small in particle size, and high in purity and dispersibility; the technology is simple; operation is convenient; cost is low; equipment requirement is low; the preparation method is green, and is friendly to the environment; cerium oxide yield is large; operation processes are continuous and adjustable; experiment process is easy to control; and industrialized production can be realized conveniently.

Description

technical field [0001] The invention relates to the technical field of preparation of inorganic nano-materials, in particular to a nano-cerium oxide and a preparation method thereof. Background technique [0002] Cerium oxide (CeO 2 ) is a cheap and versatile light rare earth oxide, which has been used in luminescent materials, polishing agents, ultraviolet absorbers, automobile exhaust purification catalysts, chemical decolorizers for glass, and radiation-resistant glass. The physical and chemical properties of cerium oxide may directly affect the performance of materials. For example, the addition of ultra-fine cerium oxide can not only reduce the sintering temperature of ceramics, but also increase the density of ceramics; large specific surface area can improve the catalytic activity of catalysts; , is also important for luminescent materials. [0003] At present, the preparation methods of cerium oxide mainly include solid-phase method, liquid-phase method and gas-pha...

AI Technical Summary

Problems solved by technology

The solid-phase method is to prepare products through solid-solid reaction at high temperature. It has the advantages of large output and simple and easy preparation process. However, the solid-phase method is easy to mix impurities, resulting in insufficient product purity and large particle size distribution. It is only suitable for In occasions with lower requirements, it is generally used less

The liquid-phase method mainly includes precipitation method, sol-gel method and microemulsion method, etc. Among them, in the process of preparing nano-scale oxide powder by precipitation method, the three stages of precipitation reaction, drying and roasting will lead to different degrees of agglomeration; The sol-gel method uses metal conjugates that are not easily hydrolyzed (such as inorganic salts or metal alkoxides) as raw materials, reacts with water in a certain solvent, gradually gels through the process of hydrolysis and polycondensation, and then dries and Calcination to obtain the required cerium oxide powder can make the particle size reach the nanometer level, but the preparation process is more complicated, and a large amount of acid or alkali is needed in the production process, which will inevitably pollute the environment; the reaction conditions of the microemulsion method are easy to achieve, The particle size obtained is small and controllable, but the amount of surfactant and solvent consumed by this method to manufacture ultrafine particles is large, and the cost is high

Gas-phase method refers to the method in which two or more simple substances or compounds undergo chemical reactions in the gas phase to form new nano-scale compounds, including sputtering method, electrified heating evaporation method, volatile compound mixing method and laser-induced chemical vapor deposition, etc. However, the conditions required for the above gas-phase method are severe, the control of the reaction conditions is also high, and the equipment is expensive, the output is low, and it is not easy to popularize.

In summary, the gas phase method, solid phase method, and liquid phase method currently used to prepare cerium oxide have certain defects, which will limit the industrial production and application of nano-cerium oxide to a certain extent.

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