Block Carbon (Activated Carbon Block Filter)
Activated carbon block is a blend of fine activated carbon (e.g., 80 X 325 mesh activated carbon), water, and a suitable binder (such as polyethylene or a similar material) that is mixed and molded and hardened or extruded to a cartridge filter of any size and shape. Sometimes specialized media are added along with activated carbon to provide customized performances for specific contaminants. The binder is particularly designed and chosen to hold the carbon and other media in a fixed solid matrix, yet, not to plug up the pores of the activated carbon. Even though the binder does occlude a portion of the adsorption sites, the finer mesh size gives activated carbon block filters faster adsorption kinetics and generally two to four times greater adsorption capacity than equivalent volumes of loose granular activated carbon. Activated carbon block filters typically have a 0.5 to 1 micron filtration capability, making it also helpful for particulate filtration, insoluble lead reduction, and demonstrating, in some cases, removal of Giardia and Cryptosporidium.