Activated carbon is a very small carbon particles have a large surface area, and carbon particles there are more small holes - capillary. This capillary has a strong adsorption capacity, due to the large surface area of the carbon particles, they are able to fully contact with the gas (impurity). When these gases (impurities) across the capillary is adsorbed from the purification. Research on surface area of activated carbon is very important, the specific surface area of activated carbon test data only using the BET method detected the result is true and reliable, there are many domestic equipment can only do direct contrast detection method. At home and abroad than the surface area of the test stage unified multi-point BET method, at home and abroad to develop the specific BET surface area measured by standard test methods are based on the basis of, see China National Standard (GB / T 19587-2004) - BET gas adsorption solid material determination of the specific surface area of the principle of the method.
2. Mechanical properties
⑴ granularity: Using a standard sieve method was determined to stay in and through each sieve weight of activated carbon, showing the particle size distribution.
⑵ contemplation density or bulk density: Diet pore volume between the particles and the void volume of the weight per unit volume of the carbon.
⑶ bulk density and particle density: Diet pore volume between the particles without diet void volume weight per unit volume of activated carbon.
⑷ strength: that of activated carbon resistance to breaking.
⑸ abrasion: the abrasion or anti-friction properties.
These directly affect the mechanical properties of activated carbon applications, such as: density affect container size; powder charcoal filter thickness influence; particle size distribution affect carbon flow resistance and pressure drop; crushing effects of activated carbon life and waste carbon regeneration.
3. Chemical properties
In addition to physical adsorption of activated carbon adsorption, and chemical adsorption. Activated carbon adsorption depends both on the pore structure, and depending on the chemical composition.
Not only activated carbon containing carbon, and containing a small amount of chemical binding, functional groups started oxygen and hydrogen, e.g., a carbonyl group, a carboxyl group, phenolic, lactones, quinones, ethers. The upper surface contains oxides and complexes of some derivatives from a raw material, some upon activation, is generated by the action of air or water vapor when activated. Sometimes generate surface sulfides and chlorides. In the activation of raw materials contained in the minerals become concentrated to the activated carbon in the ash, the main components of ash are salts of alkali metals and alkaline earth metals, such as carbonates and phosphates.