The carbon used for the filter cartridge is produced by milling a source of carbon - such as coconut carbon (coconut) with exclusion of oxygen at 1000 degrees to cook impurities. The material is then subjected to steam of 1600 degrees to "activate" the carbon.
The vapor leaving the carbon granules to form cracks and pores to allow to accumulate a large amount of chemicals. A carbon cartridge 9 3/4 inches has an area equivalent to 65 hectares. Carbon removes contaminants in two ways: by adsorption, contaminants are attracted to the surface of activated carbon and maintained at it in the same way a magnet attracts and holds the iron filings. It acts as a catalyst to change the chemical composition of some contaminants.
Activated carbon is ideal to remove chlorine, organic chemicals such as many types of pesticides, THMs such as chloroform and many VOCs are gasoline components, solvents and industrial cleaners.