Activated carbon can be classified into different types depending on the production method, appearance, function, and pore size. From the shape, it can be divided into granular activated carbon and powdered activated carbon, and granular activated carbon is including amorphous forms and shaped forms. Depending on the raw materials, activated carbon can be divided into Wood based, Coal based, Nut shell based, Petroleum and Regenerated activated carbon. According to the different functions of application, it can be divided into liquid adsorption, catalytic performance, and gas adsorption of activated carbon. Based on production methods, it is divided into physical activated carbon, chemical activated carbon, physical and chemical activated carbon. The specific classification and main application are shown in Table 1-5.
Classified from the shape of the appearance, the current common classification of activated carbon is shown in Table 1.
shape | characteristic |
Powdered activated carbon | Majority of particles of activated carbon with an apparent size of less than 0.18 nm (about 80 mesh). In addition to powdered activated carbon produced from wood chips, it also includes powdered products from granular activated carbon. |
Granular activated carbon | Majority of particles of activated carbon with an apparent size of larger than 0.18 nm (about 80 mesh). which can be divided into fragmented, spherical and hollow micro-spheres in shape. |
Crashed activated carbon | Coconut shell activated carbon, coal-based activated carbon belongs to this category, and the outer surface of activated carbon is angular due to breakage. |
Spherical activated carbon | Activated carbon which is activated after making charcoal into a spherical shape and carbon using spherical resin as raw material. |
Hollow micro-spheres carbon | Most of them are made of resins, sometimes the diameter is less than 50μm. Less powders are produced when they are using. |
Fibrous activated carbon | Activated carbon with a diameter of 8-10μm made from fibrous materials, including several types: Filamentous, cloth and felt. |
Honeycomb activated carbon | Activated carbon extruded into honeycomb. |
Activated carbon molding | There are products which activated carbon powder is attached to a substrate such as paper, nonwoven fabric or sponge, and a molded article in which activated carbon is processed into various shapes by using alone or in combination with other materials. |
Table 1 Classification of Activated Carbon based on Shape and appearance
According to the different raw materials, the classification is shown in Table 2.
type | raw material |
Wood based activated carbon
| Activated carbon made from wood, charcoal, etc. |
Nut shell based activated carbon
| Activated carbon made from coconut shell, walnut shell and apricot core |
Coal based activated carbon | Activated carbon made from lignite, peat, bituminous coal, anthracite, etc |
Petroleum activated carbon | Asphalt-based spherical activated carbon made from asphalt and other raw materials |
Regenerated carbon | The regenerated carbon, which is reactivated from the used carbon, is different from the original carbon |
Table 2 Classification of Activated Carbon from Different Raw Materials
According to the different manufacturing methods, the classification is shown in Table 3.
Activation method | Activator |
Activated Carbon by Chemical Activation | Chemical drugs such as zinc chloride, phosphoric acid, potassium hydroxide and sodium hydroxide |
Activated Carbon by Strong Alkali Activation | Potassium hydroxide, sodium hydroxide, etc. |
Activated Carbon by Gas Activation | Steam, carbon dioxide, air, etc. |
Activated Carbon by Steam Activation | Steam |
Table 3 Classification of active groups in different manufacturing methods
The classification is shown in Table- 4, depending on the use place of activated carbon.
Gas phase application | Exhaust treatment, air purification, solvent recovery, deodorization, gas separation, gas desulfurization denitration, process of refining (carbon dioxide gas, and air pressure, etc.), semiconductor gas refining, molecular sieve, radioactive gases keep gas, wet, flavouring, gas chromatography agent, filling agent, gas analysis in preservation, remove ozone, no smoke filtration, adsorption storage of natural gas, etc |
Liquid phase application | Highly purified water treatment, ultra-pure purified water treatment, water purifier, factory drainage treatment, decolorization and refinement, purify blood, remove free chlorine, recovery of gold, for brewing, for detoxification and so on |
Catalyst | Catalyst, catalyst carrier, used for one-time boiling furnace, etc. |
Table 4 Classification of Activated Carbon in Different Places of Use
Activated carbon can also be classified according to its function, as shown in Table 5.
Activated carbon | function |
Activated carbon with high surface area | Activated carbon with high surface area of more than 2500m2/g, made by strong alkali activation method. |
Molecular activated carbon | The aperture is very small and it is used to separate gases. |
Loaded activated carbon | On the surface of activated carbon loaded with metal salts and other chemicals, used for deodorization, catalyst and other occasions. |
Biological activated carbon | One of the ways for water treatment is to make the surface of activated carbon form microbial membrane,through the decomposition of microorganisms for purification. Combined with ozone treatment, it is used for high treatment of water purification. |
Table 5 Classification of Activated Carbons with Different Functions
