Activated Carbon Adsorption Properties
The adsorbent properties of activated carbons are closely related to their surface area, universal adsorption effect, highly microporous structure, and a high degree of surface reactivity. The availability of favorable pore size makes the internal surface accessible and enhances the adsorption rate. Activated carbon with a specific surface area of 800 to 1500 m2/g is widely used in many applications. This surface area is contained predominantly within micropores that have effective diameters smaller than 2 nm. In fact, a particle of active carbon consists of a network of pores that have been classified into micropores (diameter smaller than 2 nm), mesoporous (diameter between 2 and 50 nm) and macropores (diameter larger than 50 nm). The macropores do not contribute significantly toward surface areas but act as conduits for the passage of the adsorbate into the interior mesopore and the micropore surface where most of the adsorption takes place.