Inorganic silica gel is a highly active adsorption material, which is usually prepared by reacting sodium silicate and sulfuric acid and undergoing a series of post-treatment processes such as aging and acid foaming. Silica gel is an amorphous substance, and its chemical formula is mSiO2. nH2O. It is insoluble in water and any solvents, non-toxic, tasteless, chemically stable, and does not react with any substances except strong alkalis and hydrofluoric acid. Various types of silica gel form different microporous structures due to their different manufacturing methods. The chemical composition and physical structure of silica gel determine that it has many characteristics that other similar materials are difficult to replace: high adsorption performance, good thermal stability, stable chemical properties, high mechanical strength, etc., household use as a desiccant, humidity Regulator, deodorant, etc.; industrially used as oil hydrocarbon decolorizer, catalyst carrier, pressure swing adsorbent, etc.; separation and purification agent for fine chemical industry, beer stabilizer, paint thickener, toothpaste friction agent, matting agent, etc.
According to the size of its pore size, silica gel is divided into: macroporous silica gel, coarse pore silica gel, type B silica gel, and fine pore silica gel. Due to the difference in pore structure, their adsorption properties have their own characteristics. Coarse-pored silica gel has a higher adsorption capacity when the relative humidity is high, while fine-pored silica gel has a higher adsorption capacity than coarse-pored silica gel when the relative humidity is low. Type B silica gel has a pore structure between coarse and fine. Between the pores, the amount of adsorption is also between the coarse and fine pores.
Inorganic silica gel can also be divided into beer silica gel, pressure swing adsorption silica gel, medical silica gel, color-changing silica gel, silica gel desiccant, silica gel opening agent, and toothpaste silica gel according to its use.
