Method for preparing micropowder of bismuth oxide

Abstract

A preparation method of ultrafine bismuth oxide powder. The invention relates to a preparation method of oxide powder. It is characterized in that metal bismuth is put into the reaction furnace, the vacuum degree is 10-1000Pa, heated to 900-1500°C, and oxygen is introduced at a flow rate of 10-200L / min, the reaction time is 1-2h, and cooling and sedimentation are obtained. The ultrafine bismuth oxide powder. Powder particle size D 50 Within the range of 0.5-6.0 μm, the purity is >99.9%. The method of the invention can directly prepare bismuth oxide powder from metal bismuth, has short process flow, simple equipment, less investment, no pollution, easy realization of continuous industrial production, and controllable particle size and shape of the powder.

Description

technical field [0001] The invention relates to a preparation method of oxide powder, in particular to a preparation method of ultrafine oxide powder. Background technique [0002] Bismuth oxide-based powder materials have excellent optical, electrical, and magnetic properties. In addition to being widely used in electronic ceramic powder materials, electrolyte materials, photoelectric materials, high-temperature superconducting materials, catalysts, etc., they are also widely used in nuclear waste absorption materials, picture tubes, etc. Shadow mask coating, non-toxic fireworks, etc. have good application prospects. At present, there are many methods for preparing ultrafine bismuth oxide, which are divided into wet method and fire method. The wet method mainly includes chemical precipitation method, sol-gel method, self-combustion synthesis method, and solid-phase reaction method; the fire method includes liquid mist combustion method. , plasma method, etc. However, the ...

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Problems solved by technology

Due to its simple process and low cost, it is easy to realize large-scale production, but the disadvantage of this method is that the precipitation product is complicated, and it is difficult to control the particle size and uniformity of the powder

[0004] Chinese patent 94113621.3 discloses a process for producing superfine bismuth oxide with a particle size of less than 0.01 mm by using bismuth nitrate and lye in one-step reaction with the addition of a small amount of dispersant. There is no report on particle size distribution and powder purity

[0005] Chinese patent 92107155.8 discloses that the molten metal bismuth is atomized into fine liquid droplets through a gas atomization device, and simultaneously burned in the atomization chamber to generate bismuth trioxide fine powder with an average particle size ranging from 1 to 8 μm, but the equipment is complicated. High requirements on equipment, difficult to achieve continuous industrial production