Review on the technology for the production of activated carbons

The term activated carbon in its broadest sense includes a wide range of carbon-based materials prepared to exhibit a high degree of porosity and an extended interparticulate surface area. These are obtained by combustion, partial combustion, and thermal decomposition of various carbonaceous substances of cellulosic, mineral and polymeric nature. Activated carbon may be in powdered, granular or fibrous forms. The granular form is characterized by large internal surface and small pores, whereas the finely divided powdered form is associated with larger pore diameters but a smaller internal surface. Fibrous activated carbons are particularly outstanding in their physico-mechanical properties and high chemical resistance. In this article, successive stages of technology development, of activated carbons in powdered, granular and fibrous forms from precursors of different origin, have been thoroughly reviewed.