How Activated Carbon Air Filters Work
Activated carbon air filters are made up of a vast matrix of molecular-sized pores. These pores are highly absorbent, chemically bonding to odorous, gaseous, and liquid contaminates.
Activated carbon is a charcoal treated with oxygen. This process opens millions of tiny pores between the carbon atoms, resulting in a highly adsorbent material.
Today's usual activated carbons are made from coal, peat, coconut shells, and wood. Working like charcoal "sponges," they adsorb from the air or water many types of organic compoundslike benzene, toluene, and acetonitrile, as well as metals such as lead.
Activation opens millions of microscopic pores in the carbonized shells, enabling them to hold onto chemical molecules like benzene. Another step, called oxidation, confers a negative charge to the shells that helps capture metal ions, such as those in solution.
Today's activated carbons are so porous that a single gram can have over 900 square meters of surface area. A pound can have up to 465,000 square metersowing to the materials' micro-, meso-, and macro-sized pores.
You can learn more about activated carbon on the USDA website.
Activated Carbon is effective at removing the following chemcials: