Granular Activated Carbon
is a method of filtering that uses a bed of activated carbon to remove contaminants and impurities, using chemical adsorption.
Each particle/granule of carbon provides a large surface area/pore structure, allowing contaminants the maximum possible exposure to the active sites within the filter media. One pound (454 g) of activated carbon contains a surface area of approximately 100 acres (~40 Hectares).
Activated carbon works via a process called adsorption, whereby pollutant molecules in the fluid to be treated are trapped inside the pore structure of the carbon substrate. Carbon filtering is commonly used for water purification and in air purifiers.
Active charcoal carbon filters are most effective at removing chlorine, sediment, volatile organic compounds (VOCs), taste and odour from water.
Typical particle sizes that can be removed by carbon filters range from 0.5 to 50 micrometres.