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Characteristics of silica gel desiccant: silica gel desiccant is a highly active adsorption material, usually with sodium silicate and sulfuric acid reaction, and by aging, acid bubble and a series of post-treatment process and made. Silicic acid belongs to amorphous substance, its chemical molecular formula mSiO2, NH2O. Not compatible with water or any solvent. It is non-toxic, tasteless and chemical property stable. It does not react with any substance except strong alkali and hydrofluoric acid. Different types of silica gel form different microporous structures because of their different manufacturing methods. Because of its chemical structure and physical structure, silica gel has many characteristics which can not be replaced by other similar materials, such as strong adsorption, good thermal stability, chemical property stableshigh mechanical strength, etc. .