What is a Carbon Filter?

Carbon is a substance that has a long history of being used to absorb impurities and is perhaps the most powerful absorbent known to man. Activated carbon is carbon which has a slight electro-positive charge added to it, making it even more attractive to chemicals and impurities. An activated carbon filter is typically made up of petroleum coke, bituminous coal, lignite, wood products, coconut shell, or peanut shells, all of which are sources of carbon. This material is activated by subjecting it to high temperatures (2300 °F) and steam in the absence of oxygen. This process produces a carbon substance with many small pores and thus a very large surface area, which is then crushed to yield a granular. Activated carbon filters are usually rated by the size of the particles they are able to remove, measured in microns, and generally range from 50 microns (least effective) down to 0.5 microns (most effective). Granular activated carbon (GAC) is more commonly used in private water systems. Depending on the characteristics (particle size, pore size, surface area) of the granular carbon used, these units are effective for removing organic chemicals in industrial waste and trace organics, lead, and taste and odors in drinking water. Activated carbon treatment has its limitations. It does not soften water or remove bacteria, viruses, most dissolved metals, hydrogen sulfide, fluoride, or nitrates. The carbon filter in our True Water Bar is 0.5 microns and there are two of them to ensure removal of these toxins. Source- http://waterquality.cce.cornell.edu/publications/CCEWQ-03-ActivatedCarbonWtrTrt.pdf