Separation of liquids, gases, colloids or suspended matter from a medium by adherence to the surface or pores of a solid. The physical process occurring when liquids, gases, or suspended matters adhere to the surfaces or in the pores of an adsorbent media such as activated carbon. This is a physical process (there is no chemical reaction). In wastewater treatment, adsorption is an advanced method of treating wastes in which activated carbon removes organic matter from wastewater.