Method of manufacturing silicon micropowder
I. Overview
Silicon micropowder is an important raw material for the production of chemicals, which is widely used in the fields of electronics, ceramics, coatings, plastics and so on. With the continuous progress of science and technology, the manufacturing methods of silicon micropowder have also been continuously developed and improved. This article will introduce several common manufacturing methods of silicon micropowder.
II. Physical method
The physical method is to crush natural quartz sand or fused silica into micron or submicron powder by mechanical crushing, ball milling, airflow milling and so on. The advantages of this method are simple process and low cost, but the product purity is low and the particle size distribution is wide.
1. Mechanical crushing method
Mechanical crushing method is to make silica micropowder from natural quartz sand or fused silica through crushing, grinding, grading and other processes. The key equipments of this method are mill and classifier, and the commonly used mills are ball mill, Raymond mill, airflow mill and so on.
2. Airflow milling method
Airflow milling method is to use high-speed airflow to accelerate the material to supersonic speed, so that the material is crushed by mutual collision and friction at the nozzle. This method has fine particle size and high purity, but the equipment investment is large and energy consumption is high.
Third, chemical method
Chemical method is a method of preparing silicon micropowder through chemical reaction, including gas phase method, liquid phase method and solid phase method.
1. Fumed-phase method
Fumed-phase method is through silane gas oxidation reaction at high temperatures, generating silica particles, collected, processed to obtain silica micropowder. This method has high product purity and narrow particle size distribution, but the equipment investment is large and energy consumption is high.
2. Liquid-phase method
Liquid-phase method is through the chemical reaction in solution, to generate silica particles, after separation, drying to get silica micropowder. Commonly used liquid phase method are sol-gel method, hydrolysis method, etc.. This method has high product purity and controllable particle size distribution, but the process is more complicated.
3. Solid-phase method
Solid-phase method is to generate silica particles through chemical reaction between solid materials, and get silica micropowder through crushing and grading. This method is simple and low cost, but the product purity is low.
Four, comprehensive method
Comprehensive method is to combine the advantages of physical and chemical methods, through a number of steps to prepare silica micropowder method. The commonly used synthesis method has mechanical chemical method, physical chemical method and so on.
Mechanical-chemical method is through the chemical reaction under the action of mechanical force to generate silica particles, and then crushed and graded to get silica micropowder. This method combines the advantages of mechanical crushing and chemical reaction, with high product purity and narrow particle size distribution.
Physical-chemical method is through the combination of physical and chemical methods, first in solution to generate silica particles, and then crushed by mechanical crushing or air milling to get silica micropowder. This method has high product purity and controllable particle size distribution, but the process is more complex.
V. Conclusion
There are various manufacturing methods for silicon micropowder, and each method has its advantages and disadvantages and scope of application. When choosing the manufacturing method, it is necessary to make comprehensive consideration according to the product requirements, equipment conditions and production costs. In the future, with the continuous progress of science and technology and the improvement of environmental protection requirements, the manufacturing methods of silica micropowder will be continuously improved and optimized.
