Adsorption

Adsorption, the taking up by the surface of a solid or liquid (adsorbent) of the atoms, ions, or molecules of a gas or other liquid (adsorbate). Porous or finely divided solids can hold more adsorbate because of the relatively large surface area exposed. Similarly, the adsorbent surface of a quantity of liquid is increased if the liquid is divided into fine droplets. In some cases, the atoms of the adsorbate share electrons with atoms of the adsorbent surface, forming a thin layer of chemical compound. Adsorption is also an important part of catalysis and other chemical processes. Absorption occurs when the molecules of adsorbate penetrate the bulk of the solid or liquid adsorbent.