The main benefits of silica sol

Silica gel can be used as a desiccant and can be reused. Silica gel is a porous material with different particle sizes formed by proper dehydration of silicic acid gel mSiO2·nH2O. It has an open porous structure, a large specific surface (surface area per unit mass), 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 make it acidified, 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 off the soluble salts with hot water, dry it at 60~70℃ and activate it at about 300℃ to get 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. When it is used as a desiccant, it is blue before absorbing water, and turns red after absorbing water. From the change in color, we can see the degree of water absorption and whether it needs regeneration treatment. Silica gel is also widely used in steam recovery, petroleum refining and catalyst preparation.