What is Silica
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What is Silica
General term for white powdery X-ray amorphous silicic acid and silicate products, mainly referring to precipitated silica, fumed silica and ultrafine silica gel, also including powdered synthetic aluminum silicate and silicic acid calcium etc. Silica is a porous material whose composition can be represented by SiO2·nH2O, where nH2O exists in the form of surface hydroxyl groups.
Soluble in caustic alkali and hydrofluoric acid, insoluble in water, solvents and acids (except hydrofluoric acid). High temperature resistance, non-flammable, odorless, odorless, with good electrical insulation.
Silica is roughly divided into precipitated silica and fumed silica according to the production method. Fumed silica is a white amorphous flocculent translucent solid colloidal nanoparticle (particle size less than 100nm) under normal conditions, which is non-toxic and has a huge specific surface area. The fumed silica is all nano-silica, the product purity can reach 99%, and the particle size can reach 10~20nm, but the preparation process is complicated and the price is expensive;
Silica, as an environmental-friendly and high-performance additive, is mainly used in rubber products (including high-temperature vulcanized silicone rubber), textiles, papermaking, pesticides, and food additives. Judging from the growth rate of white carbon black production in the four years from 2004 to 2008, the four-year compound growth rate was 13.3%. In 2009, there were more than 60 silica production enterprises in my country, with a production capacity of about 1 million tons and an output of 750,000 tons. China's production and sales ranked first in the world.
Benefiting from the growth in demand in tire manufacturing, silicone rubber industry, coatings industry, new energy and other fields, it is expected that the average annual demand growth rate of my country's precipitation silica (silicon dioxide) will be about 10% in the future. In 2015, Asia will become the largest market for highly dispersed silica, and its demand growth rate will be much higher than the global average growth rate of 9%, reaching 15% or higher. China accounts for 40% of the Asian market and will become the world's largest single market.