Silicone can be used as a desiccant and can be reused. Silica gel is a Msio2 NH2O material with different size due to the proper dehydration of silicic acid gels. With an open porous structure, which is larger than the surface (unit mass surface area) and can adsorb many substances, it is a good desiccant, adsorbent and catalyst carrier.
Silica gel adsorption is mainly physical adsorption, can be regenerated and reused. In alkali metal silicate (such as sodium silicate) solution to add acid, so that acidification, add a certain amount of electrolyte to stir, that is, the formation of silicic acid gel, or in a thicker sodium silicate solution add acid or ammonium salt can also produce silicate gel. The silicic acid gel will be placed for several hours to aging, and then wash away with hot water soluble salts, drying under 60~70℃ and in about 300 ℃ when activated, you can get silica gel. The silica gel is soaked in cobalt chloride solution and then dried and activated, which can be changed to the color-changing silicone. Use it as a desiccant, the water before the suction is blue, after the water to red, from the color changes can be seen water absorption degree, and whether the need to regenerate treatment. Silica gel is also widely used in steam recovery, oil refining and catalyst preparation.