Method for preparing zirconium oxide micro powder

Abstract

A method for preparing zirconium oxide superfine powder, characterized in that ammonia water and zirconium salt are reacted in a solution by co-precipitation, and the resulting precipitate is added to the zirconium oxychloride solution after being washed and filtered to make the precipitate produce Peptization, using the sol as the crystallization core, continuously and slowly adding zirconium oxychloride solution, heating to further hydrolyze the solution to produce precipitation, washing, calcining and grinding the hydrolyzate to prepare a uniform and uniform nano-zirconia super fine powder. The invention solves the problem of uncontrollable crystallization nucleation and growth process and uneven primary particle size in the prior art, and the prepared zirconia primary particle size is controllable, uniform, high in quality, low in preparation cost and high in efficiency. .

Description

technical field [0001] The invention relates to a method for preparing zirconia superfine powder. The powder prepared by the method has uniform particle distribution and compact structure, and is mainly used for preparing high-strength and high-density structural ceramics. Background technique [0002] Existing methods for preparing zirconia ultrafine powder include: uniform precipitation method, co-precipitation method, heating hydrolysis method, etc. [0003] Uniform precipitation method: Mix zirconium oxychloride and urea solution evenly, heat it above 70°C, urea will decompose, and the decomposition reaction equation is as follows: [0004] <chemistry num="001"> <chem file="200410064520_cml001.xml" / > < / chemistry> [0005] With the continuous decomposition of urea, the ammonia water produced will continuously increase the pH value of the solution. To a certain extent, the viscosity of the solution will suddenly increase, and precipitation will occur...

AI Technical Summary

Problems solved by technology

The consequence is that the crystallization of the particles is not perfect, and there are holes in the primary particles.

[0007] Hydrolysis method: Heating the zirconium oxychloride aqueous solution to a certain temperature to continuously volatilize hydrogen chloride. After the pH value rises to a certain level, the solution spontaneously nucleates to form a crystal core, and the prepared ultrafine powder is inconsistent in size. In addition, it is heated It takes a long time, usually takes 5-10 days, consumes a lot of energy, and the cost is high

Images