3. Ceramic adsorbents for gas and vapor capture

Atoms or molecules (adsorbates) are attached to the surface of a solid (adsorbent) by physical adsorption or physisorption (weak bonds between adsorbed species and the solid surface) or chemical adsorption or chemisorption (chemical reaction between adsorbed species and the solid surface).

An example relating to the first case is that of "silica gel", a hydrophilic mesoporous silica (SiO ₂ ), developing a large specific surface area. Atmospheric water adsorbs on its surface and condenses by capillary condensation in its pores