Submicron yttrium oxide and preparation method thereof

Abstract

The invention relates to submicron yttrium oxide and a preparation method thereof. The preparation method comprises the following steps of: in the presence of a compound precipitator formed by oxalic acid and one oxalate of ammonium oxalate, ammonium hydrogen oxalate, sodium oxalate, sodium hydrogen oxalate, potassium oxalate and potassium hydrogen oxalate, adding a yttrium nitrate and / or yttrium chloride solution into a base solution under certain reaction conditions, regulating the pH value of precipitation size, filtering and washing precipitate for a plurality of times, drying, and calcining to obtain the submicron yttrium oxide. The yttrium oxide has the physical properties that D50 is less than 1.0Mum and more than 0.1Mum, D90 is less than or equal to 1.0Mum, the particle size distribution coefficient Q is less than or equal to 0.20 and the particles are square or spherical in shapes. The invention has the advantages of simple process, operation easiness, low requirement on equipment, low production cost, convenience in production process control, good precipitate dispersibility and filtering property in a technological process, easiness in implementation of industrialized production and stable quality of the prepared product.

Description

technical field [0001] The invention relates to a submicron yttrium oxide product and a preparation method thereof, and belongs to the technical field of preparation of rare earth oxide powder materials with special physical properties. technical background [0002] Yttrium oxide is an important rare earth oxide. Yttrium oxide has a broad application prospect due to its unique electronic layer structure, high valence, strong polarizability, diversity of electronic energy levels and spectral lines, and active chemical properties of rare earth elements. Yttrium oxide powder is an important ceramic raw material, which belongs to the cubic crystal system. It has excellent heat resistance, corrosion resistance and high temperature stability. Its melting point is greater than 2400 ° C and its dielectric constant is 12-20. Yttrium oxide powder can be made into a polycrystalline ceramic material with excellent transparency. This ceramic has high linear transmittance in the infrared...

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Problems solved by technology

[0006] 2. Spray pyrolysis method, which uses spray equipment to spray and pyrolyze the raw material solution at a certain temperature to obtain oxides. It is characterized in that it is completed from solution to powder in one step, without filtering and drying, sintering and pulverization, and the powder particles are small and well dispersed. Agglomeration, controllable particle size, continuous production, and large output, but there are not many applications of this method at present, mainly because the cost of equipment is too high, the requirements for raw materials are high, product collection is difficult, and the generated ultrafine particles Many of them are hollow

[0007] 3. The sol-gel method, the cation is first made into a soluble organic complex, and then further heated and evaporated into a sol and a gel, and finally the gel is dried and calcined at a lower temperature to obtain an oxide. The components are mixed intermolecularly, the particle size of the product is small, the uniformity is high, and the reaction process is easy to control; the reaction is carried out at low temperature, which avoids the appearance of high temperature phase, so the product has high purity and good chemical uniformity. The particles are small, the particle size distribution is narrow, and the chemical activity is large; however, this method has high cost, long cycle time, and low yield. It is difficult for the gel to become a dry superfine powder, and it is easy to agglomerate. The shrinkage is large, and a large amount of smoke is produced during calcination, which is not conducive to environmental protection

The advantage of the precipitation method is to precisely control the chemical composition, especially the ultrafine powder with uniform components; the superfine powder material has high surface activity, low production cost, simple process, and low equipment requirements. However, the particle size of the product prepared by the ordinary precipitation method is relatively large, and the particle size is not easy to control and the distribution is not ideal.

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