Silica gel desiccant is a highly active adsorption material, which is usually prepared by reacting sodium silicate with sulfuric acid, aging, acid bubble and a series of post-treatment processes. Silica gel is an amorphous substance, and its chemical formula is mSiO2. nH2O. It is insoluble in water and any solvent, non-toxic and tasteless, with stable chemical properties, and does not react with any substance except strong base and hydrofluoric acid. The chemical composition and physical structure of silica gel determine that it has the characteristics that many other similar materials are difficult to replace. Silica gel desiccant has high adsorption performance, good thermal stability, stable chemical properties, high mechanical strength, etc