Activated charcoal and zeolites are both categorized by having pores equal to or smaller than what size?
Activated carbon Activated carbon, also called activated charcoal, is a form of carbon processed to have small, low-volume pores that increase the surface area available for adsorption or chemical reactions. "Activated" is sometimes substituted with "active".
Permeable reactive barrier A permeable reactive barrier (PRB), also referred to as a permeable reactive treatment zone (PRTZ), is a developing technology that has been recognized as being a cost-effective technology for "in situ" (at the site) groundwater remediation. PRBs are barriers which allow some—but not all—materials to pass through. One definition for PRBs is an "in situ" treatment zone that passively captures a plume of contaminants and removes or breaks down the contaminants, releasing uncontaminated water. The primary removal methods include: (1) sorption and precipitation, (2) chemical reaction, and (3) reactions involving biological mechanisms.