What Does Adsorption Mean?
Adsorption is the adhesion of atoms in the liquid or gas phase to the surface of another material. During adsorption, a thin layer of atoms clings to a material's surface; this thin layer is called the adsorbate. The material surface that is being adhered to is known as the adsorbent.
Adsorption is used for a variety of applications. Adsorption and its reverse process, desorption, are used to separate different elements during chromatography. Activated charcoal is frequently used to filter water and several other types of liquids. Zeolites are used for purifying natural gas. Adsorption is also a process that is frequently used to provide material coatings that enhance performance or prevent corrosion.
Corrosionpedia Explains Adsorption
Adsorption and absorption are two processes that are often confused with one another. Although they are similar phonetically, the actual process undergone in each is quite different. Adsorption is a process in which atoms in the liquid or gas phase adhere to a material's surface. Absorption is when atoms enter into a body of another material and are engulfed by it. Absorption deals with volume, adsorption deals with surface area.
There are many different types of adsorbents and adsorbates. While a given adsorbate may adhere well to one adsorbent, it may not do so with another type of adsorbent. The likelihood and degree of adhesion is situation dependent. Examples of adsorbents include:
- Activated carbon
- Activated alumina
- Silica gel