Silica gel (硅胶) Name: silicone rubber is a kind of high active adsorption material, belonging to the non crystalline material, its molecular formula is mSiO2 nH2O. Insoluble in water and any solvent, non-toxic and tasteless, stable chemical property, in addition to alkali, hydrofluoric acid does not react with any material. Various types of silicone rubber for different manufacturing methods and the formation of different pore structures. Silica gel chemical composition and physical structure, determines that it has many other similar materials to replace features: high adsorption properties, good thermal stability, chemical stability, high mechanical strength. According to the pore size of silica gel is divided into: the macroporous silica gel, porous silica, silica gel, silica gel B type pore.