Therefore, it is first aggregated into larger particles in the aggregator, and then collected by the rotary air separator, and then sent to the deacidification furnace to purge fumed silica with hot air or auxiliary steam Black to pH 3.6 or above is the finished product. At this time, the particles of fumed silica are very fine and form aerosol with the gas, which is not easy to capture. ![]() After silicon tetrachloride is gasified at high temperature, it is hydrolyzed with a certain amount of hydrogen and oxygen (or air) at high temperature. The raw material of silicon tetrachloride is sent to the evaporator for heating and evaporation, and the dried and filtered air is taken as the carrier and sent to the synthetic hydrolysis furnace. The reaction equation is as followsĪfter drying, dedusting and filtering, air and hydrogen are sent to the synthetic hydrolysis furnace. Its raw materials are silicon tetrachloride, oxygen (or air) and hydrogen, which are formed by reaction at high temperature. It is mainly chemical vapor deposition (CAV) method, also known as pyrolysis method, dry method or combustion method. The new method uses cheap nonmetallic ore as silicon source, which greatly reduces the production cost of silica. Except sodium silicate, other costs are high. The traditional method of preparing silica is to use sodium silicate, silicon tetrachloride and tetraethyl orthosilicate as silicon source. ![]() Silicon dioxide produced by special methods such as crystal method, two crystallization method or reverse micelle microemulsion method. ![]() The latter refers to the technology of high gravity, sol-gel, and so on. The former refers to silica, which is based on acid (sulfuric acid, hydrochloric acid, etc.), CO2 and sodium silicate. The purity of the product is more than 99.8%, the original particle diameter is 10~40nm, and the precipitated silica is divided into traditional precipitated silica and special precipitated silica. Fumed silica is all nanometer grade silica. It is non-toxic and has a large specific surface area (100 ~ 400m2 / g). According to the production method, silica can be divided into precipitation silica and fumed silica (scientific name: fumed silica).įumed silica is white amorphous flocculent translucent solid colloidal nanoparticles in normal state. It mainly refers to precipitated silica, fumed silica, ultrafine silica gel and aerogel, including powdered synthetic aluminum silicate and calcium silicate. White carbon black is a general term for white amorphous powder silicates and silicate products. ![]() The difference between fumed silica and precipitated silica
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