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Silica factory choose different methods to produce silica white

Date : 2017/2/28 17:07:08

Silica white is white reinforced silicon powder materials, It is the collectively of Silicate Hydrate of synthesis and silicates.Including precipitation of SiO2, Ca·SiO3, Mg·SiO3,  Al2(SiO3)3 and so on. But generally speaking mostly refers SiO2 silica white terms. The classic method of manufacturing a silica white three categories: vapor phase method, a precipitation method and from the solution. Industrial preparation methods are a combination of these three methods or improved. Different silica factory many choose different methods. As production methods, the properties and uses are different. 

The vapor phase method is the main method for the production of nanometer silica white in developed countries. Fumed silica is silicon chloride chlorotetrachloride or trichloro-methylsilane, an amorphous powder produced by high temperature hydrolysis in a mixture of hydrogen and oxygen, often spherical particles with hydroxyl and adsorbed water, particle size between 7-40nm. 

Precipitated silica white commonly used silicate (usually sodium silicate) and inorganic acid (usually using sulfuric acid) and precipitation reaction method to produce, generate hydrated silica precipitation, according to the finished product requirements, in the roller Filter or plate filter press by filtration, washing to remove excess water and reaction by-products, the silica filter cake, and then dry (usually spray drying) to get the finished product. By controlling the ratio of the material in the reaction process, the temperature and time of the reaction, the time, the post-treatment such as filtration, washing and drying can obtain different products with different specific surface area, particle size, purity, morphology, structure and porosity. Silica white production process is different, its physical and chemical properties are also different, it is just to meet the different purposes and performance requirements.

The solution method according to the use of different raw materials can be divided into non-metallic mineral method, grapefen and by-product recovery method.