Adsorption isotherm

 An adsorption isotherm is a graphical representation of the relationship between the amount of adsorbate (substance being adsorbed) adsorbed onto the surface of an adsorbent (solid material) at a given temperature and pressure. It illustrates how the adsorption capacity of the adsorbent changes as the concentration of the adsorbate in the gas or liquid phase changes.

There are several types of adsorption isotherms, such as Langmuir, Freundlich, BET (Brunauer-Emmett-Teller), etc., each describing different aspects of the adsorption process.  Adsorption isotherm