Classification and Overview of Silica
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Silica / White carbon black is the general term of white powder X-ray amorphous silicic acid and silicate products, mainly referring to precipitated silica, fumed silica and ultra-fine silica gel, as well as powder synthetic aluminum silicate and calcium silicate. White carbon black is a porous substance, and its composition can be represented by SiO2 · nH2O, where nH2O exists in the form of surface hydroxyl groups. Soluble in caustic soda and hydrofluoric acid, insoluble in water, solvents, and acids (excluding hydrofluoric acid). High temperature resistance, non flammable, odorless, odorless, and excellent electrical insulation.
Silica / White carbon black can be roughly divided into precipitated white carbon black and gas-phase white carbon black according to production methods. Under normal conditions, gas-phase white carbon black is a white amorphous flocculent semi transparent solid colloidal nanoparticle (particle size less than 100nm), non-toxic, and has a huge specific surface area. Gas phase white carbon black is entirely made of nano silica, with a product purity of up to 99% and a particle size of 10-20nm. However, the preparation process is complex and expensive; Precipitation white carbon black can be divided into traditional precipitation white carbon black and special precipitation white carbon black. The former refers to silicon dioxide produced with sulfuric acid, hydrochloric acid, CO2 and water glass as basic raw materials, and the latter refers to silicon dioxide produced with special methods such as high gravity technology, sol gel method, chemical crystal method, secondary crystallization method or reverse micellar micro lotion method. Precipitated silica is mainly used as a reinforcing agent for natural rubber and synthetic rubber, as well as a friction agent for toothpaste. Vapor phase silica is mainly used as reinforcing agent, coating and unsaturated resin thickener of silicone rubber, and ultra-fine silica gel and aerogel are mainly used as coating matting agent, thickener, plastic film opening agent, etc.
As an environmentally friendly and high-performance additive, Silica / white carbon black is mainly used in the fields of rubber products (including high-temperature vulcanized silicone rubber), textiles, papermaking, pesticides, and food additives. From the growth rate of white carbon black production from 2004 to 2008, the compound annual growth rate is 13.3%. In 2009, there were over 60 white carbon black production enterprises in China, with a production capacity of about 1 million tons and a production capacity of 750000 tons. China's production and sales volume ranked first in the world.
Thanks to the growth in demand in the tire manufacturing industry, silicone rubber industry, coating industry, new energy and other fields, it is expected that the average annual growth rate of precipitated silica (silica) in China will be about 10% in the future. In 2015, Asia will become the largest market for highly dispersed white carbon black, with a demand growth rate far higher than the global average of 9%, reaching 15% or higher. China accounts for 40% of the Asian market and will become the world's largest single market