6. Adsorption - Activated carbon

6.1 Principle

Adsorption in air treatment is the transfer of a molecule from the gas phase to a solid surface. A widespread phenomenon in nature, it is amplified here by the use of porous materials with a very large surface area.

The overall adsorption mechanism can be broken down into several phases:

• transfer of the pollutant present in the air to the external surface of the solid ;

• diffusion in internal porosity ;

• exothermic adsorption reaction, i.e. interaction between the molecule and the surface of the material;

• surface diffusion.

More detailed approaches to these mechanisms...