The processed works with silica gel as the main raw material are all called silica gel products. Silica gel is a porous material with different particle sizes formed by proper dehydration of silicic acid gel. It has an open porous structure and can adsorb many substances. It is a good desiccant, adsorbent and catalyst carrier. The adsorption effect of silica gel is mainly physical adsorption, which can be regenerated and used repeatedly. Add acid to the alkali metal silicate (such as sodium silicate) solution to acidify it, and then add a certain amount of electrolyte to stir to form a silicic acid gel; or add acid or Ammonium salts can also generate silicic acid gels. Let the silicic acid gel stand for a few hours to age it, then wash it with hot water to remove the soluble salts, dry it at 60-70°C and activate it at about 300°C to obtain silica gel. 　The silicic acid gel is soaked in a cobalt chloride solution and then dried and activated to obtain a color-changing silica gel.

Food-grade silica gel is non-toxic, tasteless, insoluble in water and any solvent, and is a highly active green product. Food-grade silica gel has inherent thermal stability (-40°C-230°C). It is suitable for different occasions. The product has good flexibility and meets different needs.