The principle of desiccant mainly includes physical adsorption and chemical adsorption.
Physical adsorption: Physical adsorption is mainly achieved through porous materials such as silica gel and activated alumina. These materials have a porous structure and can directly absorb moisture from the air by physical means. For example, silica gel has a porous structure and contains a large number of micropores and capillaries on the surface. When moisture in the air contacts the surface of silica gel, water molecules will be adsorbed into these micropores and capillaries, thereby achieving the purpose of water absorption.
Chemical adsorption: Chemical adsorption removes moisture through a chemical reaction between the desiccant and water. For example, quicklime (the main component is calcium oxide) will react chemically to generate calcium hydroxide when it comes into contact with water, and release heat, thereby consuming moisture and achieving the purpose of reducing air humidity.
