Is Activated Carbon an adsorbent or absorbent?

Activated carbon is classified as an adsorbent because it functions through the process of adsorption, not absorption. In adsorption, molecules from a gas, liquid, or dissolved solid adhere to the surface of the activated carbon particles. This occurs due to various physical and chemical interactions, such as van der Waals forces and electrostatic attractions, which create a high surface area that effectively traps impurities.

Activated carbon's structure features numerous pores, providing an extensive surface area that enhances its ability to capture contaminants. This characteristic is particularly beneficial in water treatment processes, where activated carbon is widely used to remove organic compounds, chlorine, and other substances from water by adsorbing them onto its surface.

The distinction between adsorbent and absorbent is significant. Absorbents draw in materials throughout their bulk, which is not the case with activated carbon, as it only interacts with substances at its surface. Therefore, identifying activated carbon as an adsorbent clarifies its functional role in various applications, especially in advanced water treatment.